The Best Tankless Water Heater Reviews for 2020
Updated by Brandon F. on August 26, 2020
Are you in the market for a new tankless water heater for your home, apartment, RV, or business? Then you have come to the right place! There are dozens of different popular water heater brands that offer literally thousands of different products to choose from. Trying to find the right one to meet your needs can be a daunting task!
We are here to make things easier for you. We have put together an enormous listing of many of the top water heater brands so that you have all of the information at your fingertips.
We spent over 150 hours testing products, consulting experts, and researching companies to create this Tankless Water Heater Ultimate Guide.
Best Tankless Water Heaters – Top 5 Picks
The Competition
One thing is for certain: there are a lot of tankless water heater brands to choose from! Not only that, but each brand can offer dozens or more different products. It is easy to become overwhelmed with what is out there. To help with this, we have broken down the various brands below. You can click on any brand to be taken to a full review of it.
American Standard
Buy on Amazon $1,199.00 and save
American Standard is a very respected name in the water heater world. They specialize in both residential as well as commercial water heaters and offer up tankless condensing water heaters, natural gas water heaters, electric water heaters, and more. As for their tankless water heater models, you can choose between the TCWH180S-AS and TCWH199S-AS. Both models have a lot to offer but do come at a rather high asking price.
Aquah
Buy on Amazon $319.00 and save
AQUAH is in the business of nothing but tankless water heaters. Their product selection is quite large and includes natural gas, liquid propane, gas propane, and electric water heaters. Within these categories they also offer various sizes that have different features and outputs. AQUAH seems to aim at finding a happy medium between performance and price.
Assortit
Buy on Amazon Price not available and save
Assortit is an online company that sells a variety of items on marketplaces such as Amazon. They don’t seem to have any particular niche that they focus on. Instead, they have a little bit of everything. Their selection of tankless water heaters is quite small, with their 110V/3000 Watt electric water heater being their only model. It is very reasonably priced but might not have enough power for many people’s needs.
Atmor
Buy on Amazon $349.99 and save 22%
Atmor is one of the leading suppliers of electric tankless water heaters in the entire industry. The focus specifically on electric water heaters for residential settings. There are currently 5 different series. These include the Atmor New, Atmor Completa, two versions of the Atmor Inline, and the Atmor ThermoPro. Each model will have its optimal target audience and all are priced at a level that makes them within budget for most people.
Bosch
Buy on Amazon $219.30 and save
Bosch is one of the most recognized brands in this review. They specialize in all sorts of products in a variety of industries. Within the home heating sector, they have quite a few tankless hot water heaters. Specifically, they sell both electric and gas water heaters in a wide range of sizes and outputs. Their proven efficiency and great reliability have made them one of the top-selling water heater brands for many years, but it does come at an above-average asking price.
Camplux
Buy on Amazon $239.99 and save 20%
Camplux focuses mostly on camping-related accessories. Within this category, you will find a few different tankless water heaters. Specifically, Camplux has both indoor and outdoor gas water heaters. They will vary in water displacement and intended applications but all follow a very similar design approach. As for costs, they tend to fall about the middle of the road compared to other options available.
Chronomite
Buy on Amazon $159.95 and save
Chronomite has been around since 1966 and their business is strictly on electric tankless water heaters. They have three primary categories that they specialize in: Point of Use Mini Water Heaters, Point of Use Water Heaters, and Large Capacity Water Heaters. Each of these models will come with its own unique features, specs, and intended applications. But from a price standpoint, all models seem to be reasonable and within most people’s budgets.
Denshine
Buy on Amazon $105.99 and save
Denshine is a smaller brand that sells a host of items on various online marketplaces. Their selection of tankless water heaters is quite small. We only know of one model that they carry: an 8L electric unit. Because of this, your applications will be quite limited. But it does come in at a very reasonable price.
Dltsli
Buy on Amazon $70.59 and save 26%
Dltsli is another brand that sells various items in many different product categories. Their tankless water heater selection is limited to just two models. And both models are, more or less, the same (outside of some aesthetics). These water heaters are powered by electricity and are intended for small applications such as having hot water for a shower. And due to their simple nature and small power output, the asking prices are very affordable.
EccoTemp
Buy on Amazon Price not available and save
EccoTemp is another one of the premier water heater companies in the industry. They prioritize efficiency and have a variety of models that include electric, liquid propane, and natural gas. Their prices are on the higher side but they promise some of the best performance and reliability in the industry.
EcoSmart
Buy on Amazon $448.35 and save 25%
EcoSmart is one of the best-selling brands of tankless water heaters in the country. They have a very large selection of sizes that span both electric and gas units. Their popularity can be attributed to their fantastic performance, impressive efficiency, and their warranty. But these will creep up in the price scale because of this.
Eemax
Buy on Amazon $189.99 and save 36%
Out of all of the manufacturers that we have reviewed, Eemax likely has the largest selection of tankless water heaters. They have residential, commercial, and industrial solutions and their product catalog spans into the thousands! Their expertise lies in electric water heaters and they don’t offer gas models. We will be focusing primarily on their residential water heaters. Eemax has many years of experience and they promise excellent performance, superior efficiency, and great build quality. But it does come at a high asking price.
Excel
Buy on Amazon $219.00 and save 27%
Excel deals in gas and electric water heaters in addition to piping systems, gas meters, and a few other odds and ends. Their lineup of tankless water heaters is quite small. Currently, there are four types of gas-based water heater and one type of electric water heater (in addition to some heated shower heads which we won’t be testing in this review). Asking prices are quite fair and fall into the mid-price range.
EZ Tankless
Buy on Amazon $144.95 and save
EZ Tankless might not have the largest selection of tankless water heaters, but what they do have is certainly unique. While most brands will focus on just electric or gas units, EZ Tankless has some products that we rarely see. These include condensing tankless water heaters, direct vent tankless water heaters, and forced exhaust tankless water heaters. In addition to this, they also have a couple of smaller portable water heaters. These are, for the most part, larger units so the asking price will go up accordingly.
Gasland
Buy on Amazon $129.99 and save
As the name suggests, Gasland focuses primarily on gas-powered devices. They have gas water heaters in addition to other gas applicants and kitchenware. They also offer various accessories necessary to make the most of their products. From a design standpoint, they are going to be very similar to camping-inspired brands such as Camplux. Their models offer modest performance but are very convenient and affordable.
iHeat Tankless
Buy on Amazon $199.99 and save
iHeat Tankless is a small-scale operation that deals exclusively in electric water heaters. They have a few different models to choose from that begin with their convenient Mini series and scale up to units large enough to power an entire home. These are very intuitive models with just the right amount of bells and whistles and the asking prices are about mid-level.
Lotus
Buy on Amazon Price not available and save
Lotus is an online retailer that sells items in just about every niche you can think of. We could only find one Lotus tankless water heater, however. And it is a smaller unit that runs on electricity and is really designed for small applications (mostly point of use). While it is on the small side, the main selling point for it is the price.
Marey
Buy on Amazon $232.99 and save
Marey has a diverse range of tankless water heater that includes both gas and electric models. These units are intended for all sorts of applications ranging from small Point of Use units all the way up to heater that can handle the demands of an entire home. With Marey tankless water heaters you will get proven performance and reliability along with a great warranty. However, they do creep up into the higher price ranges.
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Navien is one of the premier tankless water heater manufacturers in the world. They have a huge list of products that span between residential, commercial, and residential. We will be focusing on residential models. Specifically, Navien has three types of water heater to choose from: traditional gas water heaters, combi-boilers, and boilers. Navien’s performance and features will rival any company in the industry. However, they are also among the most expensive.
Noritz
Buy on Amazon $850.00 and save
Noritz is another brand that has been synonymous with quality tankless water heaters for many years now. They have departments that specialize in both residential as well as industrial/commercial but for this review, we will be just talking about their residential units. You will find a very diverse selection of models to choose from that can meet just about any residential demands that you can throw at them. All Noritz water heaters are designed to run off of either propane or natural gas. That being said, asking prices do tend to creep up into the premium price tier.
Rheem
Buy on Amazon $1,189.00 and save
Rheem is one of the most diverse brands that we have reviewed in this ultimate guide. Not only do they have a nice selection of tankless water heaters but they also have air conditioners, pool heaters, thermostats, and more. As for their tankless water heater selection, they have all of the popular types: mid-efficiency gas, high-efficiency gas, electric, and point of use. And their asking prices, while not the cheapest, are aligned with your typical consumer’s budget in mind.
Ridgeyard
Buy on Amazon Price not available and save
Ridgeyard is a smaller online company that deals primarily on various marketplaces such as Amazon. It has a variety of products including its attractive set of indoor water heaters. All of these models are gas powered (either propane or natural gas) and go by other names including MountainNet or Fastar. You will find that these models are extremely affordable but, as you might have guessed, with lower costs come sacrifices in performance and features.
Rinnai
Buy on Amazon $1,510.00 and save 26%
Rinnai advertises as having the #1 selling tankless water heater, and for good reason. Their huge lineup of tankless water heater, gas home heating, and accessories can rival anyone else in the industry. For this review, we will be focusing on their residential tankless water heaters. These are all gas-powered units that promise impressive performance and optimal efficiency. You will also find loads of great features and an impressive warranty but it does come at a high asking price.
SioGreen
Buy on Amazon Price not available and save
SioGreen takes a change of pace compared to most other brands we have reviewed in this ultimate guide. Instead of utilizing traditional heating methods such as propane, natural gas, or electricity, SioGreen implements Infrared technology to heat water. SioGreen states that the key benefits of this approach are minimizing the likelihood of corroding parts as well as up to a 60% improvement to efficiency. Their lineup consists of a variety of Point of Use and residential units that we will discuss further below.
Stiebel Eltron
Buy on Amazon Price not available and save
Stiebel Eltron is in the business of heating things up. Not only do have a very diverse selection of both residential and industrial water heaters but they also have heating solutions for the home, hand dryers, and more. We will be focusing on their residential tankless water heaters. In the future, we would love to go into details about their tank water heater options including their very unique solar and geothermal solutions but that is outside of the scope of this review.
Takagi
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Takagi tankless water heaters take a very proven and straightforward approach in their large lineup. They focus on larger models that are designed to power entire bathroom(s) and don’t have much in the way of Point of Use devices. In addition, they deal strictly in propane and natural gas units and have a specified model of each power output that runs off of each. Asking prices are about average considering the power and features you are getting. And one of the shining beacons with these models are their robust build quality.
Thermoflow
and save
Thermoflow sells some assorted items in various niches including soldering equipment, welding equipment, and tankless water heaters. Their models are all electric-powered and are really designed to handle anything from a single sink up to a couple of bathrooms. There are a couple of notable features but overall power output isn’t anything incredible. And this results in a very reasonable asking price among all models.
Titan
Buy on Amazon $243.00 and save 13%
Titan water heaters focus primarily on electric-powered models. These models are actually connected to Niagara Industries but have been given the Titan brand name. There are currently two product lineups to choose from: the SCR2 and the recently-released SCR3. And while the SCR3 still seems to be expanding, the SCR2 offers various models with power output to meet most residential needs, be it large or small. Asking prices tend to hover around the mid-range to upper mid-range category.
Vevor
Buy on Amazon $108.99 and save 13%
Vevor is a Shanghai-based company that sells a huge array of various items that span just about every product category that you can think of. As for their tankless water heaters, we could only find one power source for their products: liquid natural gas. In addition, the heat source was the same for every model with the only difference between models being the capacity. These models are extremely affordable and fall well into the budget price tier.
WiseWater
Buy on Amazon Price not available and save
WiseWater is a lesser-known company to us but we became more familiar with it when writing this ultimate guide. They are actually sold online by a retailer called AB. Their lineup is small but powerful. We discovered both gas and electric models that were all on the “large” side and designed to handle multiple points of use at the same time. Asking prices are fair considering their posted performance numbers.
Zinnor
Buy on Amazon $102.99 and save 49%
Zinnor is another online company that sells many different items in tons of different industries. They don’t really seem to focus in on any particular type of product but instead opt to “sell it all”! Their selection of tankless water heaters is quite small. We have only come across two models by them (one electric and one gas) and both are designed for very similar applications.
Rating Metrics
When shopping for a new tankless water heater, there are a lot of considerations that have to be made. When you are spending this kind of money on a product that is going to do an important task such as provide hot water to your home or residence, doing proper research beforehand is essential.
To simplify things, we have come up with 5 different rating metrics that we think you should consider before buying. These are topics that are commonly considered when searching for a new tankless water heater. We will list each below as well as provide a short description of each.
Performance
Performance relates to how well the water heater is at being a water heater! Specifically, we will look at what sort of heating power the unit can produce. This includes its maximum flow rate as well as the water temperature rise that it can produce at various flow rates. Other considerations include how efficient the unit is (since higher efficiency means cheaper operating costs for you) as well as other specifications such as minimum flow rate requirements or if it is designed to handle one task (Point of Use) or multiple.
Features
This rating metric analyzes the various features that the water heater has. Some features help in optimizing performance but there are also plenty of other features as well. These features can be put in to make the product more user-friendly, more customizable, and easier to maintain and repair.
We like water heaters that aim to be extremely easy to use while offering up the flexibility to dig deep into customizing and monitoring for those techy people who want to go down that route.
Reliability
As the name suggests, reliability focuses on how reliable a product is. Tankless water heaters can be quite expensive so you want something that is designed to last. Not only that, but a water heater going out means that you are also out of hot water! And in certain climates and/or during the winter, this can lead to dangerous situations.
We value units that have a proven track record of being reliable. This can be attributed to using premium materials, taking extra precautions during the manufacturing process, and simply having historical experience in this product line. Also, we look into the type of warranty a company
Cost
Always an important criterion, cost discusses how expensive (or cheap) a particular model is. Just about everybody is on some sort of budget and making your money go farther is always an important consideration.
That being said, we won’t simply rate a product higher because it is cheaper. Instead, we compare the performance, features, and reliability of a product to other similar products on the market. And if one is noticeably more affordable than another, we take note of that. Tankless water heaters are a really good example of a product that sometimes is better to spend a bit more to enjoy a much more reliable and efficient product.
Overall Rating
The Overall Rating paints a “big picture” of the product or brand. It considers the other metrics outlined above to come to an overall consensus about whether or not the product is worth purchasing. Typically, anything with 3.5 stars and above is a good buy. Anything with 4 stars is a great buy. And any products lucky enough to receive 4.5 to 5 stars are a fantastic buy!
Full Reviews
Below are our full reviews for the various tankless water heaters that we tested. We break down the various rating metrics that we discussed above including giving each product an Overall Rating.
American Standard Tankless Water Heater Review
Models: TCWH180S-AS, TCWH199S-AS
Performance –
No matter which model you go with (TCWH180S-AS or TCWH199S-AS), you will enjoy a high-performing American Standard unit. Specifically, the TCWH180S-AS does between 18,000 and 180,000 BTU/Hr while the TCWH199S-AS bumps things up to between 19,000 and 199,000 BTU/Hr. This is good for producing 10.0 and 11.0 gallons per minute, respectively. These tankless water heaters are extremely efficient and are eco-friendly thanks to their low NOx and natural gas footprint. This makes them a great addition to any home that is looking for great water heater ability but without a huge natural gas or electric bill each month.
Features –
American Standard has successfully made an extremely easy to use lineup of water heaters. The digital thermostat located on the face of the unit is precise and makes it easy to control the temperature output anywhere from 95 degrees Fahrenheit up to 140 degrees Fahrenheit. It is also Energy Star and ETL certified. Specifically, you will find that it uses up to 55% less energy than the competition.
Reliability –
We have found American Standard tankless water heaters to be extremely reliable. All of the components are made of quality material (mostly stainless steel) and are quite thick. There can be a bit of a learning curve in installing and setting it up, but once it gets going you shouldn’t have any issues. And American Standard stands behind their product. You will find that it comes with a 12-year limited heat exchanger warranty and a 5-year limited parts warranty. This among the best in the industry and it shows us that this company is willing to stand behind its products.
Cost –
There is no denying that these are fantastic tankless water heaters. They produce adequate heat, are very reliable, and look great to boot. But this does come at a rather high asking price. Over time, however, the high initial price will be absorbed since you will enjoy some energy savings on your monthly electric and gas bill. But there is no denying that it is a pricey product.
Overall Rating –
The small lineup of residential American Standard tankless water heaters shine. Both models (TCWH180S-AS or TCWH199S-AS) do a great job of heating and should be plenty for most homes. The natural gas and/or NOx footprint is small and you will see the difference in your monthly energy bill. The display screen is intuitive and easy to read. And the warranty you will enjoy is among the best in the energy. The only negative is the high asking price. But if you are after a quality heater that won’t let you down, save up a little while longer and enjoy this fantastic performer.
AQUAH Tankless Water Heater Review
Models: JSD20-K, JSD24-K, JSD32-K, JSD12-K, JSD12K-6J, JSG32-K, JSG20-K, JSG28-K, AQE-12, AQE-18, AQS-24, AQS-27
Performance – 
As you might expect, the specific performance criteria will vary depending on which specific AQUAH tankless water heater model you are looking at. On the upper end, you will find the AQUAH Paramount units. These are available in both propane gas and natural gas models. For the propane gas model (JSG32-K), you will enjoy a thermal output of 32,000 Watts (109,260 Btu/Hr) which is good for 4.3 gallons per minute with a 45-degree temperature rise. Its sister unit, the JSG32-K Propane Gas unit, is capable of 3.7 gallons per minute with a 45-degree temperature rise.
As you move down, you will find smaller propane and natural gas units that can produce anywhere from 1.5 to 2 gallons per minute with a 45-degree temperature rise. And for those who are on a tighter budget or simply don’t need that high of heating performance, AQUAH offers up their portable electric units. These come in 3 models: The 12 kW AQE-12, the 18 kW AQE-18, and the 27 kW AQS-27. These are capable of 0.53, 0.79, and 0.85 gallons per minute, respectively. And AQUAH’s patented enclosed loop heating system helps to keep them operating at a lower energy cost.
Features –
AQUAH has focused on keeping their units cost-effective so you won’t find a huge laundry list of features on them. The most notable feature is its efficient operation. The AQUAH Paramount tankless water heaters enjoy a thermal efficiency of up to 88%. Also, the more affordable units still enjoy 85% efficiency (JSD20-K Propane unit) and an impressive 98% efficiency in the thermal units.
In addition to this, certain models will come with stainless steel front case and cover and all models (both metal and plastic) enjoy splash-proof and corrosion-proof liners. You will also be able to control temperature settings thanks to an attractive LED touch screen on the electric units.
AQUAH is also very serious about safety. All of their water heaters come with many safety features. These include overheating prevention devices, flame failure detection device, water pressure release valve, auto cutoff protection, and more.
Reliability –
We haven’t heard any major complaints with quality issues on any of the AQUAH units. Even on the lower end models that don’t utilize as much stainless steel, the components seem to work nicely for many years. AQUAH has a 5-year limited warranty on the heat exchanger and a 1-year warranty on all other components. While this isn’t the most impressive warranty we have seen, it is still good considering the asking price.
Cost –
AQUAH isn’t technically a budget lineup of tankless water heaters, but it is at a price point that should be aligned with most people. Considering the performance, features, and build quality, we feel that the asking prices are more than fair. This is particularly true on the smaller electric units that are quite affordable.
Overall Rating –
AQUAH tankless water heaters bring to the table a large and diverse selection of units. No matter if you are needing a simple heater that does a gallon per minute or a more capable model that is good for 4+ gallons, AQUAH has what you need. In addition to this, they have units that run off of all the popular mediums including propane gas, liquid propane, natural gas, and electric. The only people that may not be fulfilled are those after an extremely powerful unit that can do 8+ gallons. But for everyone else (and particularly those trying to watch their budget), AQUAH makes a good argument for your business.
Assortit Tankless Water Heater Review
Models: 110V/3000W
Performance – 
The heating performance comes thanks to the internal electrical furnace that operates at 110V and 3,000 Watts. The result is a somewhat lackluster 0.5 gallons per minute of hot water production. In addition, Assortit recommends that the initial water temperature be at least 57 degrees Fahrenheit. In other words, for those who are in northern states or countries and who have very cold groundwater, this product may struggle.
Features –
There aren’t a lot of features with the Assortit tankless hot water heater. There is a simple on/off switch and nothing in the way of an interactive LED screen. There is a notable safety feature: it comes with a pressure relief device (PRD) which, as the name suggests, will relieve excess pressure so as to not be a danger to those nearby. But other than that, this is a very Spartan unit.
Reliability –
The good thing about simple products is that there are fewer items that can break. Unfortunately, we still dealt with some quality issues with this model. Namely, the electrical heater does not seem to last as long as in higher-end models. It is also easily overwhelmed and you may find yourself running it too hard, which will further reduce the life expectancy. In addition, you won’t find the impressive 5+ year warranty that you get on higher-end models from other brands.
Cost –
Probably the biggest selling point of this model is its asking price. It is extremely affordable and among the cheapest tankless hot water heaters we have tested. But you do give up a lot for this price point. The performance, features, and reliability all took a hit.
Overall Rating –
The Assortit tankless water heater will catch people’s eyes due to its asking price alone. But upon closer inspection, you will find that there are quite a few issues. The performance is simply too low for most people’s needs and many people who live in colder climates will be unable to use it. Furthermore, the features and build quality could both use some upgrades. While your wallet may be happy with this model, save up a bit longer and buy something more capable.
Atmor Tankless Water Heater Review
Models: ThermoPro (AT-905-11TB, AT-905-14TB, AT-910-18TP, AT-910-24TP, AT-910-27TP), New, Completa, Inline
Performance –
You will have quite a selection of power choices with Atmor Electric Water Heaters. On the lower end, you will have models such as the Atmor AT-S901-03 which only produces 0.5 gallons per minute with a 45-degree temperature rise. This scales up to larger models such as the AT-S901-13 which produces 2.25 gallons per minute. And for households who are really after some serious water heating, the Atmor ThermoPro is your answer. Thanks to up to an impressive 27kW of power, it can produce over 5 gallons per minute of hot water. This is enough water to power a medium sized home that has 4 potential outlets that required hot water. And for those who need something in between, the Atmor Completa and Atmor Inline lineups will suit the job thanks to their 4 to 7 kW motors.
Features –
Like heating capacity, specific features will vary some depending on which model you go with. We must say that we were quite impressed with the lineup of features on the Atmor ThermoPro series. There is a very sleek and simple digital panel that allows for quick and easy alterations to the desired hot water temperature. Specifically, you will be able to adjust the water temperature to anything from 90 to 135 degrees. And it comes with the proprietary Atmor self-modulating smart flow technology. This greatly improves efficiency (up to 50%) which helps to reduce your energy bill every month.
Reliability –
We are quite impressed with just how reliable Atmor Tankless Water Heaters are. They are made of quality components and oftentimes stainless steel is used for the metal parts. In addition, the internal circuity is solid and you shouldn’t have to worry about electrical gremlins rearing their ugly head. This is particularly true in the ThermoPro Series. As for the warranty, it is about average for the industry. You will enjoy a 2-year limited warranty on parts and a 7- year warranty on leaks.
Cost –
As you might have guessed, the asking price will depend on which model you go with. The lower end Atmor New models are very reasonably priced but simply don’t have a high level of water output. On the higher end, the larger Inline models and the ThermoPro models will be quite a bit more but the performance and features scale up accordingly. Overall, we feel that the asking price for each unit is quite fair for what you are getting. And in all small to medium-sized homes, Atmor will have a great unit that will meet your needs.
Overall Rating –
The large and diverse lineup of water heaters that Atmor brings to the table really impressed us. They are all electric units so people who prefer propane or natural gas will be out of luck. However, for those who want to stick to electric, Atmor provides a good reason for why they are one of the most popular household water heater brands around. We do recommend saving up a bit more and springing for one of the ThermoPro models as their efficiency and reliability are great.
Bosch Tankless Water Heater Review
Models: Greentherm 9000, Therm C 1210 ES, Therm C 1050 ES, Therm C 950 ES, Therm 940 ES, Therm 830 ES, Tronic 6000C, Tronic 3000, Tronic 3000T
Performance –
With such a diverse selection of products, there will obviously be a lot of variance on specific performance numbers of a given Bosch Tankless water heater. Starting with the entry-level, you will find the Bosch Electric Mini-Tank (ES2.5, ES4, and ES8) models. These small devices aren’t designed to handle an entire house but rather a small application like during a grill out. The difference in the sizes is related to the storage capacity in gallons. All 3 examples will produce around 6.8 gallons per hour with a 90 degree Fahrenheit rise.
Up from here is the Tronic 3000 Series. These electric units come in 5 flavors (US12, US0, US7, US6, and US3) and will vary from anywhere from 0.5 to 1.8 gallons per minute depending on the desired temperature rise. And speaking of temperature rise, they are capable of up to 75 degrees Fahrenheit of it which is quite impressive!
The top of the electric Bosch models are the 5000 and 6000 Series. These are designed to handle an entire house thanks to their high water output and efficient design. They can produce anywhere from 1.6 GPM all the way up to 5.4 GPM with 150 psi of water pressure.
For those that need more power or that simply prefer gas heaters, Bosch has a huge selection for you. And with anywhere from 8.3 all the way up to 12.1 gallons per minute capacity at 35 degrees, they are powerful enough to handle even large homes.
Features –
Most of the features you will find in Bosch tankless water heaters are tied to their efficiency. These are extremely efficient units with energy factors of 0.95 and thermal efficiencies over 80%. You will find an electronic ignition and a patented burner design which is very effective at quickly lighting and beginning the heat. The controls are very precise and are easily adjustable. In the electric models, you will find an electronic flow sensor and element modulation which provides a constant output temperature. This all results in a very precise and effective system for heating water of any amount. And the higher end models such as the Greentherm 9000 will actually come with a touchscreen LED monitor which gives you added user control.
Reliability –
Bosch water heaters are among the most reliable in the industry. All of the components are made of high-quality plastics or metals and the metal is typically stainless steel. This makes them extremely rust and corrosion resistant. As for the circuitry, it is well-guarded and we have heard of no issues related to it becoming defective early on. And Bosch stands behind their products with one of the best warranties in the business. You will find a 5-year warranty on parts and anywhere from 10 to 15-year warranty on the heat exchanger. This level of protection from the manufacturer is a rarity in today’s world.
Cost –
Bosch tankless water heaters aren’t cheap. Typically, they will creep up into the premium price tier and be among some of the most expensive in the industry. But for this high asking price, you will enjoy an extremely reliable and efficient device that, over time, will save you money each month in electric bills. Consider it a long-term investment.
Overall Rating –
For those that want the best in terms of tankless water heaters, look no further than Bosch. They have a huge array of both electric and gas units of all sizes and capabilities. And all of them prioritize efficiency over all else. You will pay a lot for them up front, but the combination of efficient operation and reliability makes the high initial asking price much easier to swallow. We highly recommend checking Bosch out.
Camplux Tankless Water Heater Review
Models: AY132, BD158, BD264, BW264, BW422, CM264
Performance –
Your performance will vary depending on which model you choose to go with. For the indoor selections, Camplux appears to have diluted their options down to just one model: the CM264. This heater operates at 68,000 BTU/Hr which is good for 2.64 gallons per minute at a 77 degree Fahrenheit temperature rise. It can be powered by a 20 to 100-pound propane tank, making it a powerful solution for any camper or RV.
The larger selections come with the outdoor models. You will find that they can produce anywhere from as low as 1.32 gallons per minute in the AY132 model all the way up to 4.22 gallons per minute in the BW422 model. This is achieved from anywhere from 34,000 to 110,000 BTU/Hr of power. This is an impressive number and above average compared to what else is out there. The capable temperature rise is also quite versatile: ranging from around 45 degrees Fahrenheit all the way up to a very impressive 115 degrees Fahrenheit. One area that we do feel that Camplux is lacking in some is their efficiency. While they do produce great heat, their water heaters tend to run a bit less efficient than some of the other models available on the market.
Features –
The most notable feature with Camplux water heaters is in their low-pressure startup. You only need 2.5 psi to start up the CM264 which Camplux states is the lowest requirement on the market. In addition to this, all of the necessary regulators and adaptors are included so you won’t find yourself scrambling for spare parts.
You will also find an easy to read and adjust dial on the face of the heater. Two knobs (one for hot and one for cold) allow you to adjust the temperature like you would a typical shower. And speaking of showers, these units come with attached hoses and even a shower nozzle! And for transportation, there is an overhead carrying handle that really makes these quite portable. Overall, this is the all-in-one camping water heater that you have been looking for.
Reliability –
Build Quality is very good and we have no reports of any major issues (outside of the occasional switch faulting early). All regulators and adaptors are CAS-approved so you know that they are up to spec. And the outside shell is made of corrosion-resistant metal so you don’t have to worry about exposing it to too much water. These are reliable units that should last for many years with typical use.
Cost –
Asking prices are reasonable but it is important to remember that these tankless water heaters are really designed for very specific applications. For those looking for a more mobile unit that is intended for outdoor showers, RVs, etc., this is a great purchase. But for those who are looking for a more permanent fixture for your home, you will have to buy something that costs more but is also more capable for that type of environment.
Overall Rating –
The Camplux tankless water heater lineup is a great addition to any outdoor enthusiast who is after a heater that can quickly and easily be set up while on the go. While most portable units are severely limited in how much hot water they can produce, the larger sizes of these propane-powered units really shine in this department. You won’t find yourself running out of hot water, even while out in a cold climate. But do remember that these have a specific application. For people after a more home-friendly unit, you will likely have to shop elsewhere.
Chronomite Tankless Water Heater Review
Models: CMT-1.3, CMT-2.5, CMT-4.0, CMT-6.0, SR-15L, SR-20L, SR-30L, SR-40L, CM-12L, CM-15L, CM-20L, M-15L, M-20L, M-30L, M-40L, E-46L, E-60L, E-70L, E-80L, E-90L, E-46S, E-60S, E-70S, E-80S, E-90S, Model R-L, Model R-S, Model R-H, Model ER-L, Model ER-S, Model ER-H, Model ER, Model ER-L_3P, Model ER-S_3P, Model ER-H_3P, Model ERB-L_3P, Model ERB-S_3P, Model ERB-H_3P
Performance –
With such a huge selection of models, there will be a lot of variation in temperature ratings and heat output. Starting off with the smallest model, the mini-tank water heaters are designed to be a mobile solution for campsites, RVs, etc. These models run off 1,440 Watts and deliver a temperature range between 50 and 140 degrees Fahrenheit. The primary difference between the different models is the capacity, which will range from 1.3 gallons up to 6 gallons.
As you move up to larger models, you will be met with higher wattage and more capabilities. For instance, the CM models will run between 1,400 Watts and go all the way up to 5,540 Watts in the CM-20L/277 model. This is capable of a temperature rise of 38 degrees Fahrenheit at 1 gallon per minute. However, even with these models, they simply won’t have the capability to handle a full house.
For those who want a total home solution, we recommend going with one of the largest models. Look no further than the ERB Series (or, as Chronomite calls it, the “Boxer” Series). These models offer between 2.6 GPM all the way up to 30 GPM. And the temperature rises aren’t bad, either. You can expect around a 28 degree Fahrenheit rise when operating at 20 GPM. These are powerful units that are designed to handle just about anything you can throw at them.
It is worth mentioning that the overall performance will be a bit lower than we have seen with traditional propane or natural gas heaters. Because of this, those who are in cold climates may have to be a bit more patient when using these units. Obviously, as you scale up to larger models, this becomes less of an issue but you will pay more.
Features –
These are very intuitive tankless water heaters. They have the controls and safety features you need to get them up and running in a short time. The higher-end models such as the Boxer series actually come with a built-in microprocessor that measures temperature 120 times per second. This allows for lightning-fast tweaks which helps boost efficiency.
And speaking of efficiency, Chronomite advertises up to 99% efficiency on certain models. This is incredibly impressive and really helps you save on your energy bill every month.
The smaller models have built-in control knobs that allow you to operate it like a traditional shower. The only thing that is missing is some sort of LED display that shows the temperature and the necessary settings.
Reliability –
All of the components on Chronomite tankless electric water heaters are of high quality. The mechanisms are quite simple in how they operate, so there aren’t a lot of things that can go wrong. The outer housing is typically made of stainless steel as well as much of the hardware that holds them together. Our one issue is with the warranty. It is only a year in many cases which is a bit lower than many of the other premium tankless water heaters on the market.
Cost –
We are content with the asking prices for these units. While they aren’t the cheapest you will find, they are competitive when looking at other examples on the market. You do sacrifice a bit in performance and features but for many, the cost savings more than make up for that.
Overall Rating –
Chronomite tankless water heaters bring to the table one of the largest selections of electric water heaters that we have seen. There are sizes for all applications: from a small portable shower or sink all the way up to a unit that can power an entire small building. Electric water heaters do come with some unique traits, however. And in the smaller models, you may have to wait a bit longer to get your heat. But once going, they are great units that deliver impressive gallons per minute. And for the price, we feel that they are a great value.
Denshine Tankless Water Heater Review
Models: 1500W
Performance –
Power comes thanks to a 1500W 110V motor. This is good for delivering a temperature range of 55C to 75C (or 131F to 167F). In addition, you only need around 3 psi of water pressure to activate the unit. The biggest hurdle will simply be the lack of storage capacity. This model only has around a 2-gallon capacity. Because of this, you will have to be very conservative with your hot water use or you will find yourself running out rather quickly. And being an electrical heater, it will take more time to heat new water up to the desired temperature range. So try to avoid running long showers or baths while using this.
Features –
Being a budget-minded model, your available features will be limited. It doesn’t come with a shower nozzle or a handy overhead carrying case (both of these will have to be purchased separately). There is a control knob but nothing in the way of a temperature display. Because of this, you will have to give the water a “feel” test to see if it is at the temperature that you want. In addition, there isn’t much in the way of safety controls or microprocessors that make fine adjustments to the temperature. This will drive down efficiency and make you spend a bit more power to get the temperature up.
Reliability –
The Denshine tankless water heater doesn’t take advantage of the high-quality components that some of the more expensive units we have reviewed do. There is little in the way of an established warranty and you will be required to contact that seller directly to deal with any issues. That being said, it should still operate for a couple of years without any major issues.
Cost –
This heater has a very reasonable asking price. You are limited in your scope and the features are sparse, but for people looking for a simple and low-cost source of some hot water, this will do just fine.
Overall Rating –
The Denshine tankless water heater is your standard run-of-the-mill electric water heater that doesn’t do anything terrible but doesn’t really stand out, either. The storage capacity is small which will limit what it is capable of and the electric heater, while decent, will take above average time to heat up the water. But we can’t deny the attractive asking price and for many, this is the top priority.
Dltsli Tankless Water Heater Review
Models: 240V 5.5KW
Performance –
There are three different power levels to choose from: 3.5KW, 4.5KW, and 5.5KW. We recommend sticking to the most powerful settings as this unit is on the smaller side and needs the boost in heat performance. It needs around 1.2L/minute to activate and tops out at around 4.5L/min of water flow. Heating time is around 3 to 5 seconds and the temperature setting is from 25C to 55C. Specifically, you will find up to a 73 degree Fahrenheit temperature rise when running at a standard 1.25 gallons per minute.
Considering these numbers, the Dltsli electric tankless water heater is best used for smaller applications such as showers and sinks. Anything more than this and you will struggle to get adequate heating performance or water flow. But still, when used for its desired purpose, it operates fine.
Features –
We do like that this unit comes with three different power settings. This is something that few other electric water heaters offer. In addition to this, you will find a constantly updated temperature display that shows 1-degree increments (in Celsius). This allows you to find the exact temperature you are after instead of having to fidget with the knobs. Other great features include anti-dry functionality, water leakage prevention, and earth leakage prevention. The only feature notably missing is an included shower or sink sprayer. You will have to buy this separately. But for the asking price, we can’t complain.
Reliability –
For being a small and low-cost heater, it is very reliable. We haven’t heard any complaints about the heating element going out prematurely and all of the built-in wiring is done well. The anti-dry feature is very helpful and helps to protect the fragile components from water damage. And while you won’t enjoy the long warranty that larger, more expensive units offer, you really don’t need it here as it should run flawlessly for several years.
Cost –
We are really content with the price point of the Dltsli electric water heater. It is a bit on the small side but packs a large enough punch to be used in a variety of smaller applications. And the list of features rivals many more expensive units on the market.
Overall Rating –
Dltsli’s tankless water heater selection is basically limited to a single model. And the model is quite small and limited to less demanding applications. But for those who are only looking for a small electric water heater, it does the job quite well. There are plenty of helpful features and the small heating element can produce a surprisingly high heat rise at lower flow rates. And the build quality is more than adequate given the attractive price point.
EccoTemp Tankless Water Heater Review
Models: iE-11, iE-18, iE-24, iE-27, EM-2.5, EM-4.0, EM-7.0, EL22, EL22i, 45H, 45Hi, 45HI-LP, i12, FVI12, L5, L7, L10
Performance –
With some many different models to choose from, each product type will have its own unique performance criteria. We will briefly go over each series in this section.
The electric models will offer up some of the lowest costs and smallest performance, but they are also very convenient in that they don’t have to rely on a gas line. There are two sub-series to look at. First, are the Point-of-Use mini-tank water heaters. These are designed to hold small amounts of water and provide instant hot water. They are great for campsites, RVs, and more. Storage volumes range from 2.5 gallons up to 7 gallons.
For those who want to stick with electric but prefer something more standalone and capable, the iE series is your answer. Available in 11 to 27 kW power sources, the EccoTemp iE water heaters are great for small apartments in warm climates (for the smaller sizes) all the way up to a medium-sized home (in the largest size). All of the models offer a 40 degree Fahrenheit temperature rise at anywhere from 1.8 to 3.5 GPM.
For those who prefer gas units, there are also both natural gas and propane models. For the propane models, you have various series including the L-Series, EL Series, i-Series, and more. There are also specialty i-designated models of each that contain a remote. As for performance, you will find on the lower end, models such as the L5 will thrive at around 1.5 GPM and produce a temperature range of 50 to 140 degrees Fahrenheit. This scales all the way up to the robust EL22 and 45H models. These are capable of 3.4 GPM with a 70 degree rise all the way up to 6.8 GPM with a 35-degree rise. And all of these units are extremely efficient, oftentimes having an energy rating above 80%.
Finally, you have the natural gas models. These units will match the power and flow output of their sister liquid propane models.
Features –
As we mentioned above, Eccotemp tankless water heaters are all about efficiency. You will find automatic temperature sensors that constantly adjust to the most efficient settings for a given temperature. And there are plenty of safety features including power ventilation, child locking technology, and more. And we really like the interface and styling of these water heaters as well. Nearly every model will come with tempered front glass and an LED touchscreen display. This gives you easy control over adjusting and monitoring water temperatures. In the smaller models such as the electric heaters, you will have manual knobs but they are easy to use. Furthermore, there are some spray attachment pieces included so you don’t have to go chase them down.
Reliability –
EccoTemp tankless water heaters are among the most reliable in the industry. All of the components are of extremely high quality and you can really tell that a lot of care went into the assembly of it. Furthermore, EccoTemp stands behind these products, offering a 5-year warranty on parts and a 10-year warranty on the heat exchanger. And for those who want the peace of mind of added protection, there are silver, gold, and diamond protection plans available at an additional cost.
Cost –
As you can tell, there is a lot to get excited about here. The performance of these water heaters is fantastic and the excellent build quality and loads of features are a nice plus. But it does come at a price: the cost. You will pay well into the premium price range for an EccoTemp product. But we feel that it is well worth it.
Overall Rating –
EccoTemp Water Heaters offer up a huge lineup of electric, propane, and natural gas water heaters. And within these categories, you will find models suited for a small shower all the way up to examples that can power an entire home. And the performance and efficiency are among the best in the industry. Combine this with a host of good features and one of the best warranties in the industry and you have a home run purchase in our book. Yes, they are a bit expensive but we feel that the money you will save on boosted efficiency and a long-lasting product makes it more than worth it.
EcoSmart Tankless Water Heater Review
Models: Eco 8, Eco 11, Eco 18, Eco 24, Eco 27, Eco 36, POU 3.5, POU 4T, POU 6, POU 6T, ESG-64, ESG-84, ESG-95
Performance –
We will discuss both the electric water heaters and the gas water heaters offered by EcoSmart.
Starting with the electric models, you will find that have both Point of Use models as well as various types of larger units. For the Point of Use models, you can choose between models that range from the POU 3.5 up to the POU 6T. The smallest unit, the POU 3.5, is really designed for small applications such as a single sink or small shower. It is powered by a 3.5 kW motor and has a maximum flow rate of 0.5 GPM.
For those who need a more capable POU water heater, you can step up to the POU 6T. This unit bumps things up to a 6.5 kW motor and operation is very efficient thanks to its EcoSmart self-modulating technology.
As for the larger electric units, you will find the EcoSmart ECO Series. The smallest model is the ECO 8. It has an 8 kW heating element which makes it great for small applications or for point of use. Specifically, this results in enough power for one shower and one sink.
The ECO Series scales up, topping off with the capable ECO 36. Employing an impressive 36kW heating element, the ECO 36 is powerful enough to handle the heating needs for a large home. And to power a large home, you need a lot of flow. The ECO 36 delivers, with 3.6 GPM with 37F input water and all the way up to an impressive 8.8 GPM with 77F input water. And, while powerful, you can still expect it to stick to EcoSmart’s proven efficiency. You will find savings of up to 50% compared to lesser units on the market.
And for those who would prefer to stick with gas units, EcoSmart has you covered there as well. They have three models that have specialized units for both indoor and outdoor use. The smallest model is the ESG-64. This model allows for gas input between 11,000 and 150,000 BTU/Hr. Thanks to its efficient design, this achieves water temperature between 85F and 140F with a maximum flow rate of up to 6.4 GPM.
The largest of the units, the ESG-95, is one of the most capable units in the industry. It boasts an enormous 199,000 BTU/Hr maximum which allows for up to 9.5 GPM of flow and 140F water. And the efficiency standards are retained: EcoSmart promises an 83% recover efficiency.
Features –
The feature listing for EcoSmart Tankless Water Heaters is vast. The electric models come with an intuitive and helpful digital display that allows you to fine-tune your temperature settings down to a single degree. As we mentioned above, many models also come with self-modulating technology which drives up the efficiency to well above the industry norms (saving you money on your electric bill each month).
The EcoSmart gas units come with their own host of helpful features. You will find intelligent electronic controls that optimize the performance and keep efficiency over 80%. There are also various settings including the Water Savings Setting. The helps to greatly reduce the amount of water used. And the flow activation rate is extremely low: oftentimes being less than 0.30 GPM. Other notable features include the recirculation pump kit, maintenance alerts, system self-diagnosis, digital display, hot-start programming, Guardian overheat film wrap and more. The number of features you have at your disposal truly do feel endless.
Reliability –
EcoSmart heaters are extremely reliable. They utilize stainless steel and copper components and are loaded with safety features to keep their parameters in check, prolonging the life expectancy of the unit. And the manufacturer’s warranty is truly eye-popping. For certain units, you will enjoy a limited warranty that lasts for a lifetime! That’s right. EcoSmart are one of the few companies in the industry that offer a lifetime warranty on their products. That action alone shows us that these are high-quality units that are designed to last.
Cost –
The great performance, huge feature list, and impressive durability do come at a high asking price. These tankless water heaters will fall into the premium price range. But despite that, we feel that they are a bargain. You may go through 2 or even 3 units in the life of just one EcoSmart. And when you consider their great operating efficiency, you actually end up saving money by going with one!
Overall Rating –
EcoSmart Tankless Water Heaters are one of the industry leaders and for good reason. Their diverse lineup of electric and gas water heaters performs extremely well at various climates and altitudes. And the features on them are among the best in the industry. And when you throw in the fantastic build quality and lifetime warranty, you have one of the best water heaters around. We highly recommend that anybody who is in the market for a new gas or electric tankless water heater to add EcoSmart to their short list.
Eemax Tankless Water Heater Review
Models: Accumix, Accumix II, AutoBooster, Di-ionized, HomeAdvantage II, HotMax, LavAdvantage, Mini Tank, ProAdvantage, ProSeries, SafeAdvantage, Serious Four, Series One, Series Two, Series Three, SpecAdvantage, Three Phase
Performance –
Due to the immense size of the various Eemax tankless water heaters, it is simply impossible to discuss them all in the scope of this review. Instead, we will focus on the most popular resident-oriented series. It is worth mentioning that Eemax does a lot more than just residence water heaters. This includes series such as their Accumix and LavAdvantage (used for hand washing stations), SpecAdvantage (commercial/industrial), ProSeries (commercial point of use) and more.
Eemax has focused most of its efforts on residence heaters into their Mini Tank and HomeAdvantage Series.
The Mini Tank Series offers the following models: EMT1, EMT2.5, EMT4, and EMT6. Typical of most Point of Use models, the Eemax Mini Tank utilizes a smaller heating element and a built-in storage volume to store its heated water. The number in the model represents the storage volume in gallons. For instance, the EMT2.5 has 2.5 gallons of storage.
All of the Mini Tank models are adjustable between 50 degrees and 140 degrees Fahrenheit. They are powered by a 1440W heating element, most of which can plug directly into a standard outlet. The purpose of these models is for a single point of entry. This could include things such as a sink, single shower, or a single appliance.
For those who need something larger for your home, Eemax has the HomeAdvantage II Series. The selection of these is a bit larger. They include the HA008240, HA011240, HA013240, HA018240, HA024240, HA027240, and HA036240. The number that changes in the model number represents that power of the heating unit in kW. For instance, the HA013240 has a 13kW heating unit. All models have the same minimum and maximum operating pressure (25 psi and 150 psi, respectively). But the heating element is what steals the show. On the lower end, you can expect a maximum flow of 4.8 GPM with a 4.0 GPM temperature rise of 14 degrees and a 1.0 GPM temperature rise of 55 degrees. With the monstrous HA036240, this is increased to an 8.0 GPM maximum flow, a 3.0 GPM 30 degree temperature rise, and a whopping 2.0 GPM 91 degree temperature rise. At these power levels, the HomeAdvantage II is robust enough to handle the water needs for a large residential establishment.
And no matter which model you go with, you can rest assured knowing that it will have the fantastic efficiency that Eemax is known for. Specifically, you will enjoy up to 99% efficiency which is industry-leading and will significantly reduce your energy bill each month.
Features –
A premium tankless water heater wouldn’t be complete without a nice list of features and Eemax doesn’t disappoint. On the MiniTank, you will find easily adjustable temperature controls, a T&P relief valve, a wall bracket, field replacement element, and a tank status indicator light. For the Home Advantage Series, features include a digital temperature control indicator with down to 1 degree increments, copper immersion heating element, digital temperature display, external controls, and a dynamic flow regulator. These units are efficient and very easy to use thanks to these helpful features and more.
Reliability –
We have had no issues with Eemax products. There is a reason that they are among the most popular tankless water heaters on the market and the foundation of that is their smooth operation and durability. They are made of quality metals including copper immersion heating elements, utilize copper tops, are made of single weld designs, and come with glass-lined tanks. This results in an extremely durable product that should last for years without issue.
As for the warranty, you will enjoy a 5-year limited warranty on leaks and a two-year warranty on defects. This is among the higher warranties we have come across and is further proof that Eemax believes that their products are designed to last.
Cost –
Eemax tankless water heaters are certainly of high quality but they do come at an above average asking price. But considering the craftsmanship and capable performance, we feel that they are still reasonably priced. Also, it is important to remember that the high efficiency is one of the biggest selling points of an Eemax water heater. So while you may pay a higher up-front cost, this will be absorbed over time thanks to lower energy bills.
Overall Rating –
Eemax is one of the “old school” brands in this industry. And their knowledge and expertise is unmatched by nearly every other brand. They have an enormous lineup of products. And while many of their products are designed for commercial/industrial applications and are only electric-based, what they do have for home is still quite good. You will find that the performance and build quality is top-notch and these units will last for many years of smooth operation. Yes, they can be expensive. But you will be happy that you paid a bit extra for a great product in the long run.
Excel Tankless Water Heater Review
Models: Excel, Excel Pro, Coral
Performance –
While there are four types of gas water heaters, you could almost consider there only being two. There is a given size that runs off propane and another of that same size that runs off of natural gas. The smaller of the two models, the Excel, produces 1.6 gallons per minute while the larger model, the Excel Pro, bumps it up to 6.6 gallons per minute.
In non-optimal settings, the Excel can produce respectable numbers as well. For instance, with an inlet temperature of 40 degrees and an outlet of 150 degrees, the Excel can heat water at a rate of 0.5 GPM. If you happen to have warmer water starting out (for instance, 60 degrees), it can produce 125 degree outlet water at 1.25 GPM.
The Excel Pro is far superior in this regard. It can achieve a similar 45 degree temperature rise at 4.4 GPM. And it has a temperature output range of 100 degrees to 160 degrees. Therefore, it can be used for all sort of applications.
As for the electric heater, the Coral runs off of a 220 to 240v heating element. With its 99% efficiency, it promises to be a cost-saver on your energy bill every month. Excel hasn’t released flow rates for this model but they do state that it is good for retail outlets, offices, commercial buildings, and more.
Features –
When it comes to the propane and natural gas heaters, there are a decent number of features. The electric model, however, is somewhat barren. The Excel Pro comes with a free flue kit which allows it to be exhausted either vertically or sideways. In addition, these units are self-modulating which allows it to vary its heat output real-time. This improves accuracy, is safer, and is also more cost-effective to run.
In addition, you will find a large display panel that allows you to set and monitor your temperature. The electronic ignition is also a nice touch and takes away the headache of starting the fire. There is also a copper heat exchanger and low-pressure startup technology (can start with as little as 2 psi of water pressure).
The Excel electric tankless water heater doesn’t have many notable features, however. You won’t find any sort of thermostatic control or digital display. You will also have to source out your own piping or certain mountain accessories.
Reliability –
These quality units are made in the USA and come with high-end metals. Most notably is the completely copper heat exchanger. This robust piece of material is designed to last and is very corrosion-resistant. In fact, Excel offers up a lifetime warranty on the copper heat exchanger. Most brands only offer 5 or maybe 10 years on this piece so this really shows us that Excel stands behind their heat exchangers. The other parts have just a one year warranty. We wouldn’t complain if Excel decided to bump that up to 3 or 5 years.
Cost –
The cost vs. performance ratio here is quite good. For the price, Excel Tankless Water Heaters will perform just as well if not better than most other models. And while you won’t be overwhelmed with the feature list, most of the ones that you need are there (particularly in the propane and natural gas units). The electric unit, while not quite as capable, is also much more affordable. Overall, we are very content with the price point.
Overall Rating –
Excel brings to the table a small but capable lineup of water heaters. You essentially have two types of gas and one type of electric and they are at size ranges that make them perfect for anything from a single shower up to powering a small to medium-sized home. If we had to choose, we would pick the gas-powered units over the electric. The inclusion of some much-needed features while still keeping them at an attractive price point really caught our eyes.
EZ Tankless Tankless Water Heater Review
Models: EZ Ultra HE, EZ Deluxe, EZ Supreme, EZ 101, EZ 202, EZ Prime
Performance –
While there are notable differences between the smallest and largest models when it comes to performance, all EZ Tankless water heaters have impressive numbers. On the smaller end is the popular EZ 101. This unit is designed for off-the-grid applications such as makeshift showers, for washing farm animals, or for a sink at a campsite. It is powered by propane and will produce 0.9 GPM at a 77F temperature rise and up to 2.0 GPM at a 35F temperature rise.
For those after something more capable, you can move all the way up to the EZ Supreme. This is a monster of a tankless water heater! This unit will run off either propane or natural gas and can deliver equivalent heat as a 100-gallon storage tank water heater. At a 77F temperature rise, you will enjoy 3.2GPM and this goes all the way up to 8.0GPM at a 35F temperature rise. Also worth mentioning are the great thermal efficiency ratings. You can expect anywhere from the high 80s to low 90s in energy efficiency. This helps to save money on your gas bill while still delivering the heat that you need.
Features –
There are tons of really unique features that are exclusive to EZ Tankless water heaters. On the smaller models, you will find multiple dials for adjusting heat including flame level, water flow, and a winter/summer option. There is also an automatic ignition so you don’t have to worry about fumbling with a lighter or matches to get it going.
The larger units, which are designed more as a permanent fixture, have their own features that make them suited for this type of application. It has a full digital control monitor that helps to control the temperature. And the direct vent feature utilizes a specialized intake and exhaust to deliver the great efficiency numbers we discussed above.
Reliability –
There is a lot of engineering and testing that goes into every EZ Tankless model and when they are finally released to the public, you know that they will have most of their kinks ironed out. You will find that the components are quite robust and typically made of rust-resistant metal. And the sealed joint construction minimizes that chance of any sort of leak escaping. And the overall design itself, due to its impressive simplicity, means that there are fewer moving parts and therefore fewer things that can go wrong. The warranty is quite good as well. You will enjoy a 5-year warranty on the heat exchanger and a 1-year warranty on the other components. This warranty is about average for this caliber of tankless water heater.
Cost –
These units are extremely powerful and really can handle an impressive workload. But this does come at an above average asking price. But in terms of the R&D that goes into these designs, we feel that they are better engineered than a vast majority of the other products on the market. And that research and development don’t come cheap! And the result of all of this extra work is an extremely efficient unit that will help you save money over time. So consider it an investment!
Overall Rating –
The small lineup of EZ Tankless water heater utilizes some really unique approaches that allow them to promise impressive heat numbers while still maintaining great efficiency. They have managed to take a proven gas-based design and improve upon it thanks to their intuitive intake system. Those who like simple electric models will be out of luck and the asking price may make some penny-pinchers wince. But in terms of raw performance, EZ Tankless is at the lead of the pack.
Gasland Tankless Water Heater Review
Models: 2.64GPM 10L, 1.58GPM 6L, AS150 1.5GPM 5.68L
Performance –
The name of the game here is portability. As such, you won’t see the impressive performance numbers that larger and less mobile heaters can offer. While there are 4 models to choose from, the available power sources available on Gasland Tankless Water Heaters amounts to just two. On the lower end is the 41,000 BUT/Hr heating unit (powered by propane). This is the heater of choice for the 6L and 5.68L models. It operates at between 2.18 psi and 145 psi. And it is good for up to 1.58 GPM of approximately 140F water.
The larger of the two units comes with a 68,000 BTU/Hr heating unit. Operating pressure is bumped up a bit to a minimum of 3.6 psi and a maximum of 145 psi. And the extra heating power is good for a higher flow rate: up to 2.64 GPM.
No matter which model of Gasland heater you go with, they have very similar intended applications. Neither is really designed to handle the needs of an entire home. Rather, they are best used for single applications such as a sink, shower, or bathroom. Anything more than this and you may find yourself running out of hot water!
Features –
Since the main focus here is mobility and simplicity, most of the various components you need to hook this unit up and start using it are present. This includes the hoses, gas inlet connectors, and even a shower head. Also, you will find easy-to-use adjustment knobs (one for hot and one for cold). There is a slightly upgraded model that includes an additional knob that accounts for the outside climate and it also gives with a digital display that shows the current water temperature. We really appreciate the inclusion of this and feel that it is worth the slight upcharge.
Reliability –
The build quality is acceptable here but in order to make the water heater as portable as possible, sacrifices had to be made to cut down on overall size and weight. Because of this, the metal walls and various components might not be as thick as you would have hoped. That being said, it seems to operate without a hitch. The warranty is a bit lackluster, though. You will only get a 1-year warranty. This is in comparison to other models that we reviewed that offered 5, 7, or even lifetime warranties. But for the price, we can’t be too picky.
Cost –
The best selling point of Gasland tankless water heaters (outside of their mobility) is their asking price. They are extremely affordable and should be within most people’s budgets. For those who are after something simple for a small bathroom on an RV or other outdoor settings, this unit will do just fine and save you money in the process.
Overall Rating –
Gasland has a small lineup of propane-powered water heaters that can really be diluted to just two. In addition, both serve very similar purposes and for many people, they simply won’t have the power that they are looking for. But for those after the specific application of an outdoor shower or sink area, this unit works great and is quite affordable.
iHeat Tankless Tankless Water Heater Review
Models: Mini Elite 67, Mini Basic A10, Mini Basic Plus H4, Mini Basic Plus H7, Basic Plus S4, Basic Plus S7, Basic Plus S9, Basic Plus S12, Basic Plus S14, Basic 16, Ultimate Model 11, Ultimate Model 14, Ultimate Model 16, Basic Plus S16, Ultimate 18, Ultimate 21, Ultimate 24, Ultimate 27
Performance –
There are quite a few different iHeat Tankless models to choose from, each with their own intended applications.
Starting with the smallest examples, the Mini Series are intended for compact installations under sinks our countertops and their heat output is designed to handle that type of application. Model power ranges from 3.5KW on the A-35 model and goes up to 6KW on the A-67 model. This is good for a 47 degree temperature rise and an 80 degree temperature rise at 0.5 GPM, respectively. You will also enjoy up to 60% savings on water cost thanks to the improved efficiency of this unit compared to other models out there.
For someone who is after a water heater that is a bit more capable, in comes the S Series. These models can be used for either point of use or whole house applications. They come with updated flow technology and the added benefit of advanced power modulation to boost efficiency. This results in up to 60% savings on hot water. There are quite a few more model choices here. Starting with the smallest model, the S-4, you will find a 3.5kW heat exchange that is good for a 24F temperature rise at 1 gallon per minute. This scales up somewhat linearly all the way up to the large S-16 unit. The iHeat Tankless S-16 utilizes a powerful 16kW heat exchanger which can produce anywhere from 109F temperature rise at 1.0 GPM up to a 27F temperature rise at 4.0 GPM. At this level, you have enough heating power to handle multiple rooms in a house.
Lastly, are the cream of the crop in this lineup. The AHS series takes what the S Series started and adds more. It still utilizes the intelligent electronic controls to boost efficiency but does so at a larger scale. The “small” model, the AHS11D, has an impressive 11KW heat source running at 240V. This can run at anywhere from 1.0 GPM all the way up to 4.0 GPM with a temperature rise of 81F and 20F, respectively. This scales all the way up to the absolutely enormous AHS27D, which is iHeat Tankless’ largest model. This unit has a 27Kw heater which produces an impressive 184F temperature rise at 1.0 GPM up to a 45F temperature rise at 4.0 GPM. These are very impressive numbers and powerful enough to handle even large homes.
Features –
You will find plenty of helpful features on iHeat Tankless water heaters. And the features will vary depending on which specific series you go with.
Staring with the Mini Series, you will enjoy advanced compact power modulation, a safety thermostat cutoff, and LED light to show temperature stages. The S Series adds a fully digital display with both Celsius and Fahrenheit options, easy grip fittings, updated flow technology with powerful microprocessors, and a waterproof control pad. And the AHS Series takes all of that and adds USB Diagnostic settings. These models really are the total package and have just about everything that you need to get up and running in short order.
Reliability –
In terms of structure, these water heaters are rock-solid. They implement stainless steel bodies and heat exchangers which are very resilient and also resistant to corrosion. The build quality is also above average from what we have seen. That being said, we have received some complaints from users who said that the control panel would sometimes go out prematurely. In addition, the manufacture warranty, while not terrible, is by no means industry-leading. In the Mini Series, the warranty is a 1-year and on the other models, you will find a 3-year warranty on the heat exchanger and a 1-year warranty on other components. It is worth mentioning that iHeat Tankless states that their units should last around 20 years, however. We just wish that they would increase their warranty to support that!
Cost –
Asking prices are on models actually isn’t that bad. As you would expect, the more powerful heater fetches a higher price tag but compared to other models with similar power outputs, the prices are more than fair. In addition, the features you get will rival just about any other product on the market. There are some minor quality issues but that doesn’t take away from the fact that these are at a great asking price.
Overall Rating –
iHeat Tankless might be a smaller operation but their lineup is quite large and hits all of the target audiences that we discuss in this review. You will find that these units, particularly on the higher end, are extremely powerful and can easily handle most typical home’s needs. In addition, there are plenty of features that help to drive up the efficiency and also make them much easier to operate. The only thing holding these water heaters back from an even higher rating is the fact that the warranty could be a bit longer. But still, for those trying to watch their budget, iHeat Tankless makes a strong case.
Lotus Tankless Water Heater Review
Models: LTS-3HP
Performance –
The Lotus LTS-3HP tankless water heater runs off of a 3.5KW electric heater. This small heating element is capable of a temperature rise of up to 45F and it has a suggested minimum flow rate of 0.5 GPM. The maximum flow rate isn’t much higher, just being 0.6 GPM. And at the maximum flow rate, you can expect just a 35F maximum temperature rise. This unit is really designed to be used in warmer climates where the inlet water temperature is at least 51 degrees. Anything lower than that and this heater likely won’t be able to bring the water to a suitable temperature. There have been quite a few complaints about this heater simply not providing the performance people are looking for. Even in small applications such as running a sink or shower, it may struggle.
Features –
This is a pretty bare-bones model in terms of features. It is not a plug in unit and will require being professionally installed and set up. This adds a lot of extra hassle to what isn’t a very powerful unit to begin with. There is a simple on/off switch with a red LED display and it comes with a pressure relief device for added safety. But beyond these things, there isn’t much to write about.
Reliability –
This is a very lightweight model that can easily hang off of any sink unit. In order to achieve this lightweight quality, the shell of the heater is made of thin plastic along with most of the components. The result is a product that won’t be as resilient as more expensive metal water heaters. However, Lotus does offer up a pretty nice warrant. There is a 2-year warranty on parts and a 7-year warranty on leakage.
Cost –
The Lotus tankless water heater is very competitively priced. In fact, it is among the most affordable units we have tested. This does come with some major sacrifices that we outlined above, however. From a performance standpoint, it is lackluster at best. In addition, you don’t get many features to work with. But for those on a super tight budget, it may be easier to overlook these flaws.
Overall Rating –
Lotus has its hands in a lot of different product categories and we feel that they should put some more effort into their water heaters if they hope to compete in this packed industry. Their single model, the LTS-3HP, simply doesn’t have the level of performance we were hoping. Combine that with very few features and questionable build quality, and you have an item that we can’t really get excited about. It is very affordable and the warranty is nice, but there are better options out there (even at this price point).
Marey Tankless Water Heater Review
Models: Mini Marey 110V, Aquamatic 110V, Mini Tank 10L, ECO085, Power Pak Plus 110V, Power Pak Plus 220V, ECO110, ECO150, ECO180, Gas Portable 5L LPG, Gas 5L, Gas 10L, Gas 16L, Gas 16L ETL
Performance –
Since Marey does have quite a few different models, we will break down the performance features of the electronic units and the gas units individually.
Starting with the electric models, you will find heaters that start out in the very small range. These models are Point of Use, which means that they are intended for a single specific application such as a sink or a shower. For instance, the Mini Tank 10L runs a 120V heater to pre-heat up to 10L of hot water. This allows you to enjoy water temperatures that range from 50F all the way up to 140F.
For those who want to stick with electric water heaters but need something capable, you can scale all the way up to the Marey ECO180. The ECO Series is the most powerful electric series that Marey offers and the 180 model is the headliner. It has 18kW of heating power which allows it to increase up to 4.0 GPM of water 36F. If you live in colder regions that have colder water, expect water temperatures of up to around 80F at 1.5 GPM. Furthermore, this model is powerful enough to handle multiple points of use at once. Specifically, there are connections for up to 3 different lines to run from it.
As for the gas models, Marey has a specific unit decided to run natural gas and another of equivalent power designed to run propane. And similar to their electric units, on the lower end, you will find a few different Point of Use heaters. An excellent example of this is the 5L LPG. As the name suggests, it will heat up to 5 liters of water thanks to its 35,000 But/Hr heating assembly. This is a very energy efficient unit, ranging from 54% all the way up to an impressive 87%. You will be able to heat standard faucet flow (1.5 GPM) with a temperature increase of up to 45 degrees Fahrenheit.
For something more robust, you can move all the way up to the huge Gas 16L models. The big daddy of them is the Gas 16L ETL. This model is ETL approved and is extremely efficient, saving up to 60% on your electricity bill compared to other models. The heating element comes in at 110,000 Btu/hr which can really heat up some serious water. Depending on your water input temperature and points of use, you can expect to achieve anywhere from .8 GPM to 2.25 GPM of flow with a temperature increase of 72F.
Features –
We really like the simplicity and intuitive design of Marey Tankless Water Heaters. All models come with an easy to follow interface. And in the larger units, you will enjoy SMART Technology which includes a responsive LCD touchscreen. For safety, you will find an anti-dry safety switch, automatic IC ignition system, and overheat safety devices installed on the gas models.
Another great aspect of these heaters is their extremely low water pressure startup requirements. This makes it very easy to install into a current system even if you don’t have a lot of water flow present.
Finally, many of the smaller models are designed to be an “all in one” package. You will find folding handles for carrying in addition to an included hand shower nozzle with a simple on/off control.
Reliability –
The reliability of Marey products is about average for the industry. Most of the time they will operate without issue for long periods of time but we have heard several reports of units malfunctioning relatively early on. A lot of these issues have to do with the electronics on board.
That being said, Mary does offer a pretty good warranty. You will enjoy a 5-year limited warranty on all of their water heaters. Compared to other companies, this is above average. The common numbers seem to be around 3 years so we appreciate Marey stepping up and increasing this to 5.
Cost –
You will enjoy a solid performance and some nice features with these units. Also, the warranty is pretty nice. However, the asking price can creep up. While nowhere near the most expensive models we have tested, Marey water heaters can fall into the mid to upper price range. This is particularly true on their larger gas and electric models. But if you plan on finding something powerful enough to handle an entire home, you will have to be expected to pay a bit more for it.
Overall Rating –
Marey’s lineup of electric and gas water heaters are diverse enough to hit just about every target market. You will find small Point of Use units, mid-range units, and top-of-the-line models for entire homes. The operation and efficiency are above average, particularly in the ETL models. And the features present aren’t too shabby, either. There have been some complaints about electronic issues but the company does at least stand behind their products thanks to a 5-year warranty. And the asking price, while not outlandish, may be a bit high for some people. Overall, we are content with these water heaters and wouldn’t hesitate to recommend them to someone in the market.
Models: NPE-180A, NPE-210A, NPE-240A, NPE-150S, NPE-180S, NPE-210S, NPE-240S, NCB-E, NHB-55, NHB-80, NHB-110, NHB-150
Performance –
Due to the diverse residential heating cooler lineup that Navien brings to the table, we will be breaking down the performance of each type of model. First, we will be focusing on the units you are probably most familiar with: gas-powered heaters.
Navien’s traditional gas line is comprised of the NPE-A series and the NPE-S series.
The NPE-S stands for “NPE Standard”. These units attempt to find a happy medium between Navien’s superior heating technology and cost. The heating performance comes from two stainless steel heat exchangers.
Starting at the bottom is the NPE-150S. This unit comes with 120,000 Btu/Hr of heating power. It runs at an extremely efficient 0.97 energy factor thanks to the optimal heat exchanger design. As for performance, you can enjoy a temperature rise of up to 140F at 1.7 GPM. If you are after higher flow, you can still enjoy a maximum of 30F temperature rise all the way up to 6.8 GPM. This is powerful enough to handle many typical homes’ water heating needs.
For those that want to stick with gas but need something more capable, you can go all the way up to the enormous NPE-240S. It comes with a maximum output of 199,900 Btu/Hr thanks to its dual heat exchangers. This increases the water heating capabilities significantly. You will enjoy a maximum of 2.8 GPM of low with a 140F temperature rise. And on the opposite end of the spectrum, you can flow up to an incredible 11.2 GPM at 30F rise.
Now let’s discuss the sister series: the NPE-A. This stands for “NPE Advanced”. These models, according to Navien, are the most advanced condensing tankless water heaters in the industry. This is all built around their ComfortFlow technology which further increases efficiency. There are a host of other features that we will discuss in the next section.
As for models, you can choose between the NPE-180A at the low end and the NPE-240A on the high end. These models will have very similar temperature and efficiency output as the NPA-S models but with the added features we will discuss.
Now for the special units: Navien’s condensing Combi-Boiler and Boiler models. These models have a more dedicated purpose than a traditional water heater. Their main purpose is on applications such as baseboard heating, radiators, etc. Since these fall out of the application that many people are looking for, we will keep our explanations of them brief.
The Navien combi-boiler comes in three flavors. The lowest model is the NCB-150E. It has 120,000 Btu/Hr. This is good for a 77F temperature rise at up to 2.6 GPM. The highest-end model, the NCB-240E, has 199,900 Btu/Hr. This bumps performance up to a maximum of 4.5 GPM with a 77F temperature rise.
Lastly are the Navien boilers. These are strictly intended to be used as boilers so focus on GPM isn’t really a consideration. The smallest unit, the NHB-55, has a maximum of 55,000 Btu/Hr and it can on either propane or natural gas. The largest unit, the NHB-150, increases it up to 150,000 Btu/Hr.
As you can tell, there are a lot of products here and all have impressive heating performance.
Features –
Navien’s performance is extremely impressive and potentially the only item that can trump it is its lineup of features. It is mind-boggling when you look at just how many great features you get with a purchase of one of these units.
Let’s start with the control panel. No matter which model you go with, you will enjoy a fantastic LED control panel that gives you full control of the various inputs and outputs. Furthermore, this control panel comes with Wi-Fi capabilities that allow you to tweak your settings from your smartphone.
Next, you will find that these models come with a negative pressure gas valve and a dual venture system. This allows for you to easily switch between propane and natural gas. And the dual stainless steel heat exchangers will make the most of whichever gas you decide to run. Their intuitive design is a bit reason for Navien’s industry-leading efficiency.
When you get into the higher-end models, you open up your feature list even more. The advanced models will come with Comfort Flow internal recirculation pump and buffer tank, optional HotBottom on-demand control kit, and the ability to cascade up to 16 units thanks to Navien Ready-Link Technology.
The Boilers and Combi-boilers are no slouches, either. You will enjoy features including dual input capabilities, PVC venting, field gas convertibility, cross-linkability between NCB-E and NPE units, and optional manifold kits. The turndown ratio is also extremely impressive: 15 to 1 which is an industry leader.
Reliability –
Navien products should be considered an investment. They are expensive but they come with extremely impressive warranties and top-notch customer service. The NPE-S and NPE-A have a 5-year warranty on parts and a 15-year warranty on the heat exchanger. The NCB-E comes with a 5-year warranty on parts and a 10-year warranty on the heat exchanger. Lastly, the NHB-E offers up a 5-year warranty on parts and a 15-year warranty on the heat exchanger.
As for build quality itself, all of the components are extremely reliable. You will find quality stainless steel used liberally throughout. And the electrical components are very well engineered and designed to last. As you increase the number of features and complexities in a unit, it opens up the change for more things to go wrong. While this is always a concern, Navien has appeared to iron out most of their kinks, resulting in an extremely reliable lineup of products.
Cost –
The main issue with Navien water heaters is their cost. They are extremely expensive and among the most expensive units in the industry. Those who are able and willing to pay the high entry fee will enjoy a fantastic product that is loaded with features. But for those on a tight budget, it may simply be out of reach.
Overall Rating –
We won’t beat around the bush: if you are after the very best, go with a Navien. From a performance standpoint, you won’t find much better. The ability for these water heaters to produce impressive water flow with good temperature rises is truly incredible. And when you add in on all of the features that not only greatly boost efficiency but also make it incredibly easy to operate, you truly have an industry-leader. The warranty and manufacturer support is also very reassuring. But these are extremely expensive units. If you are able to, try to save up so that you can enjoy one of the best tankless water heaters that you will ever own.
Noritz Tankless Water Heater Review
Models: NRCB180, NRCB199, EZ 111, EZ 98, CB199, CB180, EZTR40, NRCP1112, NRCP982, NRC111, NRC98, NRC711, NRC661, NR98, NR83, NR662, NR501
Performance –
There are essentially four different tiers of tankless water heaters that are offered by Noritz. They are the EZ Series, Combination Boiler Series, Mid Efficiency Series and High-Efficiency Series. We will briefly discuss the performance metrics of each below.
Starting with the EZ Series, the EZTR40 is the smallest of the units. It is designed for a large Point of Use application or the needs of a small home. Depending on your climate, this could be anywhere from 1.5 to 2 baths. It is powered by a 15,000 Btu/Hr natural gas/propane heating element. And this heating element makes it capable of anywhere from 115F to 140F at 0.5 to 6.6 GPM.
The EZ Series scales up to the most powerful of the units, the EZ111. With 199,900 BTU/Hr of heating capabilities, it can produce between 100 and 140F of water at a capacity range as low as 0.5 GPM and all the way up to an impressive 11.1 GPM.
Next up are the Noritz Combination Boilers. There are three units and all three produce very similar power outputs. Because of this, we will be focusing on our favorite of the three: the NRCB199. The NRCB199 is special in that it is the only combination boiler on the market that can provide both space heating as well as traditional domestic heating at the same time. This is thanks to its hybrid heating mode design that allows up to 199,900 BTU/hr in standard mode and 120,000 BTU/Hr in heating mode. This allows for a domestic mode of 90F to 140F and a heating mode of 100F to 180F. And both of these have a capacity range of 0.4 up to 11.1GPM.
Next up is Noritz’ mid efficiency tankless water heaters. These models aim for good efficiency and performance while helping to keep the costs down some. There is a pretty nice range of models to choose from here. Starting at the bottom is the mobile NR501. This model is designed for, at most, a single bathroom’s needs. It comes with a maximum heating rate of 120,000 BTU/Hr. This allows for up to 5.0 GPM at a 30F temperature rise. And for someone who needs a bit more temperature rise, you can still enjoy 4.2 GPM with a 45 degree rise.
The mid efficiency models cap off with the NR98. This model, thanks to its maximum 199,900 BTU/Hr gas consumption, is powerful enough to handle the bathroom needs of a standard home (2 to 3.5 baths). You will find that it produces 0.5 to 9.8 GPM with a water temperature output of 100 to 140F.
Finally come the cream of the crop: the Noritz High-Efficiency Series. This is Noritz’ largest residential model lineup and they implement the most modern technology in order to drive up efficiency and drive down energy costs.
The smallest model will be the NRC661. This water heater is designed for anywhere from 1.5 to 2 baths thanks to its 120,000 Btu/Hr heater. This is good for 0.5 to 6.6 GPM of water at 100 to 140F. And on the upper end of the spectrum is the robust NRC111. This is an extremely powerful unit and combines condensing heating technology with an impressive 199,900 Btu/Hr heating element. The result is an efficiency level over 93%.
As you can clearly see, Noritz knows what they are doing when it comes to quality residential tankless water heaters that can handle the demands on just about any home.
Features –
Overall, Noritz has a nice amount of features. Depending on which model you go with the exact features will change but, for the most part, you should find everything that you need.
Starting with the EZ Series, it is designed to be easy and simple to set up and get going. It comes with top mounted water connections which help to replace traditional tanked units. The top venting is also very versatile, allowing for multiple types of connections. Other notable features include the dual stainless steel heat exchanger as well as wi-fi capability.
The NRCB Series Combination gas boiler also comes with robust venting options. You will find the LED display very intuitive and controlling and changing the temperature is a breeze. There is also an outdoor reset control that comes with an outdoor temperature sensor. There are plenty of safety devices in place: lame rod, high limit switch, freezing prevention device, fan rotation detector, and more.
The NR Series pushes things farther. The heat exchanger is upgraded to commercial grade copper and there is a plethora of different venting options are your disposal. Direct electronic ignition makes starting it a breeze and the quick-connect feature allows two identical units to be able to be linked together. The intuitive temperature controls are still in place. Other notable features include a power cord installation kit, multiple safety devices, temperature lockout, high elevation adjustment, and more.
Finally comes the high-efficiency models. These units take everything good about the mid-efficiency models and further push the envelope thanks to its superior hybrid stainless steel/copper heat exchanger technology. There is also a PVC adapter built into the heater since exhaust temperatures are so much lower.
Reliability –
We have nothing but positives to say about the build quality and durability of Noritz Tankless Water Heaters. The components are made of stainless steel and you can really appreciate the craftsmanship that goes into each part when you inspect it. Furthermore, this company stands behind its products. Their residential water heaters come with a 5-year part warranty and either a 10 or 12-year heat exchanger warranty. This is among the best warranties in the industry.
Cost –
The major drawback of Noritz products is their prices. They fall comfortably into the higher price tier compared to other models. However, they do offer great performance, plenty of helpful features, and great construction. Because of this, you are buying a water heater that will last. Also, thanks to their efficient operation (particularly in the high-efficiency models), you will save money every month on energy bills. This can stack up to hundreds if not thousands of dollars of savings over the years.
Overall Rating –
Noritz tankless water heaters are among our favorite product lineup in the industry. They stick to a proven method of providing great heat performance in a variety of residential-friendly packages for any small to mid-sized home. The features work together nicely to create an easy-to-use and efficient heater that should last for many years without issue. They do cost a bit more than most other units we have reviewed but we feel that the slight upcharge is more than justified when you consider what you are getting.
Rheem Tankless Water Heater Review
Models: XE02P06PU14U0, XE06P06PU20U0, XE20P06PU20U0, XE10P06PU20U0, XE30P06PU20U1, RETEX-04, RETEX-06, RETEX-08, RETEX-11, RETEX-13, RETEX-18, RETEX-24, RETEX-27, RETEX-36, RTEX-04, RTEX-06, RTEX-04, RTEX-08, RTEX-11, RTEX-13, RTEX-18, RTEX-24, RTEX-27, RTEX-36, Mid Efficiency 7.0 GPM, Mid Efficiency 8.4 GPM, Mid Efficiency 9.5 GPM, Mid Efficiency 70, Mid Efficiency 84, Mid Efficiency 95, Performance Platinum Condensing 84, Performance Platinum Condensing 90, Performance Platinum Condensing 94, Performance w/ Built in Recirculation, Professional Prestige 8.4 GPM, Professional Prestige 9.0 GPM, Professional Prestige 9.5 GPM
Performance –
As you can tell from above, there are a ton of Rheem tankless water heaters to choose from. It would require a small book to break down the individual performance metrics of each model. Instead, we are going to go over the “big picture” of each series.
Starting with the smallest models, Rheem has a selection of Point of Use water heaters. These are typically designed for a single, smaller application such as powering a sink or small shower. The smallest model comes with a 3-gallon reserve tank and is powered by a 1,400 Watt heating element. We prefer the larger Point of Use models, particularly the largest 30-gallon example. In this heater, you will enjoy a much more powerful heating element, coming in at 2,000 Watts. This, combined with the larger 30-gallon storage reserve, makes it much better-suited for sink and shower applications. It is also a pretty efficient heater: It has a Uniform Energy Factor (UEF) of 0.92.
Next up are the Rheem electric water heater models. There is a huge selection to choose from and they are broken down into 2 categories: the Performance Series and Professional Series. The primary difference between the 2 series is that the Professional Series comes with self-modulating power control. As the name suggests, this allows the heater to adjust the amount of power that it is using to warm the water. This makes the unit run cheaper, cooler, and it saves you money on your energy bill each month. That being said, the overall power metrics of the Performance Series and the Professional Series are essentially the same. So for the sake of brevity, we will combine them in this section.
The smallest electric water heater will be the RETEX-04. This unit only produces 3.5kW of heating power. Water temperature can be adjusted between 80 and 140F with a flow rate that varies from 0.3 to 4.8 GPM. That being said, you will not be able to flow much water if you decide to run it on the higher temperature settings.
The electric models scale up from here: 5.5kW, 8kW, 11kW, and all the way up to the largest of the models. The RTEX-36/RETEX-36 will be the most powerful electric water heater offered by Rheem. It comes with an effective 36Kw heating element. This allows the maximum flow rate to be bumped up to 8.0 GPM with the same 80 to 140F temperature ratings of its smaller siblings.
Next up for discussion are the various mid-efficiency units. These units are specialized to run on either propane or natural gas (but not both) and the performance numbers are very similar for both.
On the low end is the 7.0 GPM model. It comes in both outdoor and indoor models and utilizes an 11,000 to 160,000 BTU/Hr heating element. It runs at a UEF of .81 to .82 (which is about average for a mid-efficiency unit). In terms of water output, you will enjoy up to 4.1 gallons per minute at a 67F rise and 6.0 gallons per minute at a 45F rise. Finally, in terms of maximum flow, it will be around 7.0 GPM. At this level, this heater can handle 2 to 3 typical bathrooms.
For someone who is after a more capable heater, you can scale all the way up to the ECO200. This unit (available in both indoor and outdoor models that run on either propane or natural gas), has a more powerful 11,000 to 199,900 BTU/Hr heating element. With this added boost, maximum flow is increased up to 9.5GPM. More specifically, you will be able to utilize up to 7.4 GPM with a 45F temperature rise and 5.0 GPM with a 67F temperature rise.
Lastly are the big dogs of the Rheem lineup: their high-efficiency water heaters. These units are broken down into two categories: The Performance Platinum Series and the Professional Prestige Series. Both units are extremely efficient but the Professional Prestige Series comes with the added benefit of a built-in condensate neutralizer.
Starting with the Performance Platinum series, the smallest model is the ECOH160. It has a 11,000 to 157,000 BTU/Hr heating element. And it employs an optimal heat exchanger and effective condensing technology to bump its UEF up to 0.93. This makes it an extremely effective water heater that doesn’t require nearly as much energy as you might think to run. In terms of water temperatures, you can choose between 85F up to 140F. If you are after maximum water flow, it can handle up to 8.4 GPM. And if you are more concerned with running hotter water, it can produce up to 4.6 GPM with a 67F rise and 6.7GPM with a 45F rise. This makes it powerful enough for most 3 bathroom homes.
If you have a larger home or simply desire higher level of heat performance, consider the top-of-the-line ECOH200. Utilizing similar technology as its younger sibling, the ECOH200 scales up the heating element to a 11,000 to 199,900 BTU/hr units. This allows for an impressive 9.5GPM of low, 8.5GPM of flow with a 45F rise, and 5.7GPM of flow with a 67F rise.
The Premium Prestige Series builds upon the solid foundation of the Performance Platinum Series. It comes in similar powered models (157,000, 180,000, and 199,900 BTU/Hr models) but utilizes high-efficiency condensing gas technology. You will enjoy similar water capabilities but with a few more money-saving operation features (with a higher initial asking price).
Lastly, if you are after the very best, consider Rheem’s new lineup of recirculating hot water heaters: the RTGH-RH11DVL and RTGH-RH10DVL. The two models offered are both extremely powerful: coming in at 180,000 BTU/Hr and 199,900 BTU/Hr. But what makes them really stand out are their insanely impressive energy factors: 0.96. In addition, these heating elements are really able to make the most of their heating power. You can expect 9.9 GPM and 11.0 GPM of max flow for the RTGH-RH10DVL and the RTGH-RH11DVL, respectively. This translates to up to 4.5 GPM at 77F temperature rise and 7.7 GPM at 45F temperature rise for the RTGH-RH10DVL and 5.0 GPM at 77F and 8.5 GPM at 45F for the RTGH-RH11DVL. These are seriously impressive numbers.
Features –
We are extremely impressed with the immense number of features that are on Rheem tankless water heaters.
You will find copper heating elements in many of the models. This his proven time and time again to provide superior heating efficiency compared to many other types of metal. In addition, all models come with intuitive digital temperature displays. These not only provide an easy-to-read display of the temperature but it also allows you to tweak the temperature down to a single digit.
The larger Performance Plus models further expand on this feature list. They have a maintenance alert setting that will alert the owner after 500 hours of use (at which time it is time for a service visit). They also come with a digital remote control so that you don’t have to physically access the heater to make changes. Other cool features include Hot Start Programming, EcoNet technology, special water savings settings, and Guardian OFW Filmwrap to provide external protection.
As you move up the product tree, the Performance Platinum and Premium Prestige take the great features of the Performance Plus models are further builds upon them. The most notable feature is the built-in condensate neutralizer. Other helpful features include recirculation pump kit compatibility, self-diagnostic capabilities, water leak detection, factory-installed translator, usage reports, and more.
Lastly are the fantastic recirculation models. As the name suggests, the real star here is the ability to recirculate water. This drives up the efficiency to near astronomic numbers. It also comes with an updated digital interface with all of the settings you could possibly need. Additional features include a crossover valve, condensate neutralizer, and on-demand activation accessories.
As you can tell, no matter which Rheem tankless water heater you go with, you will enjoy an immense number of features.
Reliability –
We have had great luck with Rheem products over the years. They have never once given us a fit. This has applied not only to their smaller and cheaper Point of Use models but all the way up to their top-of-the-line models as well. This is very important as these heaters have a lot of features and parts. More complex can mean more things can go wrong so we appreciate Rheem spending the extra effort to make sure that their products are reliable.
In addition to this, you will enjoy one of the best warranties in the industry. These water heaters come with a 5-year warranty on parts and an impressive 12-year warranty on heat exchangers.
Cost –
Rheem water heaters aren’t cheap. There really isn’t any other way to put it. While there are a handful of popular companies that make more expensive residential units, they are few and far between. But anybody reading the sections above will quickly realize that you get a ton of performance and features with any Rheem model that you go with. In addition, the longevity of the unit combined with its efficient operation means that this is more of investment than a purchase.
Overall Rating –
We are extremely impressed with what Rheem has to offer in their diverse lineup of water heaters. No matter if you go with an electric, propane, natural gas, or one of the new specialty recirculation or condensing units, you are sure to be impressed by its superior efficiency, performance, and durability. These models are not only powerful but also very easy to set up and use. Yes, they can be expensive but we would recommend that you spend twice as much on a water heater that will last 5x as long than going cheap and skimping on quality. This is one of our top choices in this ultimate guide.
Ridgeyard Tankless Water Heater Review
Models: 6L, 8L, 12L, 18L
Performance –
Ridgeyard Tankless Water Heaters are targeted at smaller applications where cost considerations might be important. They sacrifice quite a bit in the way of heating ability to remain affordable and mobile.
There are 4 models that we have come across. The smallest, the 6L model, actually runs off of propane. The small stature makes it extremely portable but significantly limits its heating output. The heating element will produce around 12kW of heat which is enough to heat approximately 1.5 gallons per minute of water up around 25 degrees. Due to its limitations, it is best used in warm climates for small applications such as a single sink.
As you scale up the model selection, you will get into models that run off either propane or natural gas (not both). You will end with the largest unit, the 18L water heater. This model runs off of liquid propane and produces up to 32kW of heat output. This is much more formidable than Ridgeyard’s smaller units and should be able to handle the heating needs of a couple of bathrooms.
Specifically, you can anticipate up to 4.75 GPM of water flow with a 77 degree temperature rise. And the thermal efficiency comes in at around 85%.
Features –
There aren’t a ton of features to discuss here. As we mentioned above, these heaters are quite portable. In fact, the smaller models actually come with built-in carrying handles. For adjustments, all models have dials on the front that control temperature and water flow. There is also a small LED temperature display on the middle dial on the largest model.
There are various safety features in place as well. This includes auto cut-off, overheating protection, flame-out protection, overpressure protection, and more. We also appreciate the electronic pulse ignition which takes the headache out of starting the flame.
Noticeably missing are some of the more advanced features such as self-adjusting heaters, self-diagnostic capabilities, and wifi. But these are budget units so we can’t be too picky.
Reliability –
The body itself has been shown to be quite robust. The stainless steel outside not only looks nice but also does a good job of protecting the sensitive internal components.
We have received some complaints from users stating that their dials can sometimes come loose or don’t spin freely. A slight adjustment and/or some lubrication might fix this issue but it is worth mentioning.
Also, you won’t get the impressive warranty that some of the other brands we have discussed offer.
Cost –
The biggest selling point of Ridgeyard Tankless Water Heaters is their fantastic asking price. They are among some of the most affordable water heaters that you can buy. Yes, they are quite limited in their scope and lack some features but for someone who wants something simple for a small application, they can accomplish that with a much smaller impact on the pocketbook.
Overall Rating –
Ridgeyard has a small but popular set of gas-powered water heaters. While none of them have the capabilities to heat an entire house adequately (in our opinion), they do serve a purpose and will thrive in smaller environments such as RVs or single bathrooms. Noticeably missing are the high-efficiency levels and more advanced operation features but at this price point, we can let that slide. This is an acceptable entry-level unit for someone on a tight budget.
Rinnai Tankless Water Heater Review
Models: RUR, RUC, RU, RUCS, RUS, RL, RLX, V, RHS100, RHS
Performance –
As you can see from browsing the Rinnai catalog, there are overwhelming numbers of tankless water heaters to choose from. They are broken down into 6 categories: high efficiency, high efficiency plus, super high efficiency, super high efficiency plus, hybrid water heating, and residential hybrid water heating.
We aren’t going to break down the specific performance metrics of each model. That would amount to a small novel! Instead, we are going to briefly discuss each series and what sort of performance range you can expect.
We will start with the high efficiency. These are going to be the most budget-minded units that Rinnai offers. Dubbed the “V-Series”, there are really 4 different models that you need to focus on: V53, V65, V75, and V94. Each of these sizes comes in various forms including indoor, outdoor, propane, and natural gas. But to simplify things, we will focus on the general performance attributes of the overall model since the individual models are very similar.
The smallest model is the V53. This water heater comes equipped with a 120,000 BTU/Hr maximum heating element that runs off either natural gas or propane (different models for each). The allows for a temperature range between 120F and 140F and a maximum flow rate of up to 5.3 GPM. In terms of specifics, you can expect up to 2.8 GPM with a 70F temperature rise and 4.0 GPM with a 50F temperature rise. It is worth mentioning that the energy factor is somewhat low here, coming in at just 0.81. Because of this, the V-Series won’t run quite as efficiently as the higher-end models.
The unit scales up through the V65, V75, and end with the most powerful model, the V94. The V94 really cranks things up thanks to its 199,000 BTU/Hr heating element. This results in a maximum flow rate of up to 9.8 GPM and individual flow rates of 4.7GPM with a 70F temperature rise and 6.6GPM at a 50F temperature rise.
Next up from this are the high efficiency plus models, the RL and RLX (we will be focusing on the RL units for this review). The primary difference between the high efficiency and the high efficiency plus models are that the plus models come with Circ-Logic Technology (more on that later) in addition to isolation valves. This helps to boost the responsiveness and efficiency of the unit while in operation. In addition to this, the RL models do away with some of the smaller sizes and focus on the two largest models: the RL75 and the RL94. They came in both propane as well as natural gas units and also have outdoor as well as indoor options.
Starting with the RL75, you will find a proven 180,000 BTU/Hr heat exchanger. This unit opens up the residential water temperature range from 98F up to 140F. In addition to this, you can enjoy up to 7.5GPM of water flow. At a flow rate of 4.3 GPM, a maximum of 70F temperature rise is possible and at 6.0GPM, you can anticipate up to 50F flow rise. This is powerful enough to handle most home’s bathroom and kitchen needs.
If you need something with a bit more power step up to the RL94. It will come with the massive 199,000 BTU/Hr heating element which allows for a maximum of 9.8 GPM of water flow. At 4.7 GPM, you can expect a 70F maximum temperature rise and at 6.6 GPM this drops downs to a 50F maximum temperature rise.
The next models are for those who are willing to spend a bit extra up front to enjoy improved efficiency. Rinnai brings to the table their popular Super High-Efficiency models that they have dubbed the SE Series.
These units implement advanced heating technology that drives the Uniform Energy Factor (UEF) up to 0.90. There are two models to choose from: the RUS65 and RUS75 (there are also RUCS models available for each but we will be focusing on the RUS).
The RUS65 is the smaller of the two water heaters. It is equipped with a 130,000 BTU/Hr gas-powered heating element. And while this heat source isn’t as large as some of the other models that we have discussed, it makes up for some of this thanks to its higher efficiency.
Residential water temperature range is restricted to between 120F and 140F and a maximum of 6.5 GPM is possible. For a 50F temperature rise, you will enjoy 4.8 GPM and for a 70F temperature rise, you still see an impressive 3.4 GPM. These numbers, while nothing eye-popping, are still large enough to handle the water heating needs of most mid-sized homes.
If you desire even higher output, in comes the powerful RUS75. It bumps the heating source up to 160,000 BTU/Hr. This increases the maximum flow rate to 7.5 GPM. In addition, you will have up to 4.2 GPM with a 70F temperature rise and 5.9GPM with a 50F temperature rise.
For those who want the very best of the best and are willing to pay, the Super High-Efficiency Plus (SE+) models will be just what you are looking for. These tankless water heaters employ an even higher efficiency (0.92) while also offering the recirculation technology and isolation valves. These units come in different flavors (RU/RUC/RUR), but will be combined here for brevity. There will be three sizes to choose from: the RU80, RU90, and RU98.
Starting with the RU80, you will enjoy 152,000 BTU/Hr of heating power. And this comes with the impressive 0.92 Uniform Energy Factor discussed above. This results in a maximum of 8.0 GPM of water flow and a temperature range of 98F up to 140F. Specifically, this gives flow rates of 4.2 and 5.9 GPM for a 70F and 50F temperature rise, respectively.
If you are after that absolute best in residential water heating, then the RU98 is the heater for you. It increases BTU/Hr to the maximum allowable 199,000 BTU/Hr rate. With a similar 98F to 140F allowable temperature range, you will enjoy 5.5 and 7.7 GPM at 70F and 50F temperature rise, respectively. Furthermore, the maximum possible flow rate is increased to 9.8 GPM. This unit is large enough to handle the demands and most medium to large homes with multiple bathrooms.
Lastly, Rinnai also offers some hybrid water heating solutions. These models can both heat water for residential use (showers, sinks, cooking, etc.) in addition to providing water use to heat floors, radiators, etc. We aren’t going to go into great detail about them but they are worth mentioning.
Features –
There are a lot of great features that go into each Rinnai tankless water heater to make them one of the industry leaders. We will briefly go over some of them in this section.
The most notable feature is wi-fi technology that is incorporated into every model. You will take advantage of the Rinnai Control-R wireless module to keep track of temperatures, make adjustments, and even run remote diagnostics on.
One thing that is noticeably missing from these models is a large LED interface. Our assumption is that Rinnai wants you to take advantage of their wi-fi capabilities and use those instead. That being said, there are some very impressive digital temperature controller accessories that can be purchased at an additional cost.
Speaking of accessories, there are quite a few of them! They include items such as termination kits, vent pipe extensions, recirculation kit components, and more. Really everything that you could possibly need to get your tankless water heater up and running is at your disposal.
The other big feature worth discussing is what is available in the Plus models. And that is the Rinnai Circ-Logic recirculation technology. This technology allows the owner to set special patterns that coincide with their personal water usage. This means that at times when you don’t typically need a lot of hot water, the water heater won’t run at as high of capacity. This ends up saving you money on your electric bill every month.
In addition to this is the ThermaCirc360. This allows you to install certain SE+ series units without having to utilize a dedicated water return line. It comes with bypass technology a timer, internal pump, bypass valve, and more.
Reliability –
Rennai has been known for their impressive reliability for many years now. When people are spending this kind of money on a water heater, they expect something that will last. And Rennai continues to deliver. All o their components are made from quality metals (mostly stainless steel) and the build quality is top-notch. No shortcuts were taken in the manufacturing and assembly process.
In addition, you will find a fantastic warranty on all models. Specifically, it is a 5-year warranty on all parts and a 12-year warranty on the heat exchanger. This is above the industry average and comparable to the very best we have come across.
Cost –
The main barrier to entry to a great Rennai tankless water heater is the cost. They are a premium water heater and, as such, fetch a premium price. But they are designed to last and their great operating efficiency (particularly on their high-efficiency models) will help to dampen the blow of the initial high sticker price.
Overall Rating –
Rennai has consistently been one of the top sellers in the water heater world for good reasons. Their impressive lineup of gas-powered heaters have the capabilities to handle just about any residential task that you can throw their way. Their efficiency numbers on the top models are among the best you will find anywhere and the cool proprietary technology they have in place to further boost energy savings really helps them to stand out. They are also very reliable and come with a very aggressive warranty. They are quite pricey but they are on our very short list for being the best tankless water heaters in the industry. Do yourself a favor, save up, and enjoy something that is truly special.
SioGreen Tankless Water Heater Review
Models: IR-20, IR-30, IR-234, IR-245, IR-260, IR-288, IR-14K220, IR-288, IR-14K380, IR-6000, IR-8000, IR-3000, IR-4000
Performance –
Depending on which SioGreen model you go with, you will find varying levels of performance. As you might have guessed from the description above, all SioGreen tankless water heaters utilize Infrared technology. You won’t find any units that require gas and, while they still require electricity to run, the method of heating is totally different from your typical electric tankless water heater.
We will start off the with smallest models that are designed for Point of Use applications. These units are meant to be used for a single purpose such as a sink or small bathroom. In addition, there are certain models that are designed to plug directly into your power grid at home and other models that are intended to be powered on RVs or other mobile vehicles.
The first unit is the SioGreen Model IR-20. This portable device runs on a 120V connection and produces 2.4kW of heating power. At this power level, its intended design is really hand wash stations. You can expect a temperature rise of around 40F at 0.3 GPM.
Most people will likely need something a little more capable (even in Point of Use situations). As you scale up the model size, you will end up at the much more powerful IR-288. This tankless water heater still works best in warm climates but has the extra power to function as a heat source for a shower and bath. It comes equipped with a 9.0kW heat source which bumps up the flow rate to 2.30 GPM with a 30F temperature rise.
Now onto the more powerful household units. These tankless water heaters utilize the same proven SioGreen technology but at a larger scale that can handle multiple points of use.
One of the smallest units will be the SioGreen IR-14K220. Thanks to its 14kW heater, it is powerful enough to handle 1 to 2 typical bathrooms. You will have a flow rate of around 1.91 GPM with a 50F temperature rise. For instance, if your input water is 59 degrees Fahrenheit then you can anticipate around 109 degrees Fahrenheit output.
This scales up to the largest of the SioGreen models, the IR-8000. This infrared tankless water heater possesses an impressive 18kW heater at 80 amps. This provides up to 3.07 GPM of flow with a 40F temperature rise (assuming 67F input water). You will also enjoy the benefit of up to 65% improved efficiency over traditional electric tankless water heaters available on the market.
Features –
Since SioGreen tankless water heaters utilize a unique way of operating, there are also some unique features on them.
The key feature present on all models are the multiple redundant high power quartz heating elements. These provide the backbone for how these infrared heaters operate.
On the smaller Point of Use models, you will find helpful features including a thermostatic intelligent temperature controller, fully modulating power control, LED temperature display, and continuous hot water on-demand function, and a self-cleaning mode. There are also a variety of safety features in place include an overheat thermal cut off fuse, high-temperature safety switch, residual leak detector, and more.
The larger units take many of the features on the Point of Use models and build upon them. You will find things such as a thermostatic intelligent fuzzy logic PID temperature controller, solid state relay, a more advanced LED temperature display, 3 digit LED flow indicator, and more. And for safety features, SioGreen utilizes many of the same ones but also includes new ones designed for the more powerful units including built-in circuit breakers.
Reliability –
From a reliability standpoint, these tankless water heaters are extremely impressive. This is due to two reasons: great construction and simple design. While many other heaters on the market utilize impressive workmanship, SioGreen is unique in that their heaters only require 5 major replaceable components. Fewer components mean fewer things that can break. Because of this, you will find that these heaters are very resilient.
In addition, the design is built around minimizing the exposure of water to metal parts. This can lead to corrosion over time. By designing to avoid this, you can a huge potential failure mode out of the equation.
As for the warranty, it isn’t quite as long as some of the other models we have seen. You will have a 3-year warranty that will cover all major parts for typical wear and tear. However, we have good experience with these heaters and never had a noticeable issue even after the 3-year mark was up.
Cost –
Infrared technology is certainly a cool approach but the asking price does creep up a bit. Since there are fewer companies doing it, there is less incentive to drive the price down. So for a given power output, you will notice that these are oftentimes more expensive than a traditional electric tankless water heater with similar power output.
But one point that needs to be made is that SioGreen tankless water heaters are far more efficient than most traditional electric water heaters. This will save you money over time and help to offset some of the higher initial asking price.
Overall Rating –
In an industry that likes to stick to its fundamental roots, it was refreshing to see SioGreen think outside of the box by using infrared technology to heat water. This approach comes with some really nice benefits including higher efficiency, a simpler design, and it helps to avoid the damage caused by corrosion. The heaters are also very reliable and attractive as well. Just be expected to pay a bit extra for this neat technology. However, we feel that it is worth it and you will save the extra money over time thanks to lower energy bills.
Stiebel Eltron Tankless Water Heater Review
Models: DHC-E 8, DHC-E 10, DHC-E 12, DHC 3-1, DHC 3-2, DHC 4-2, DHC 4-3, DHC 5-2, DHC 6-2, DHC 8-2, DHC 9-3, DHC 10-2, Mini 2-1, Mini –E 2-1, Mini 2.5-1, Mini –E 2.5-1, Mini 3-1, Mini –E 3-1, Mini 3.5-1, Mini –E 3.5-1, Mini 4-2, Mini –E 4-2, Mini 6-2, Mini –E 6-2, Tempra 12, Tempra 15, Tempra 20, Tempra 24, Tempra 29, Tempra 36
Performance –
As is typical of the larger brands, there are quite a few different types of tankless water heaters to sort through. Stiebel Eltron’s lineup is particularly diverse so breaking down each type is essential. We won’t be going into the specific performance details of each and every model but instead will paint the “big picture” for you.
It is worth mentioning that Stiebel Eltron is a bit vaguer than many brands when it comes to their efficiency. Many will happily post their energy factors and % energy savings (which can often by 50%+). However, we had a hard time tracking down energy factor statistics for these units and, in terms of energy efficiency %s, we could only find literature that mentioned 15-20% savings which is less than a lot of the competition. This isn’t a huge deal but still worth mentioning.
We will start out with the smallest models that are designed for Point of Use applications (particularly for handwashing stations). Stiebel Eltron has dubbed these models the “Mini” Series. There are actually two different models that control their power in two different ways: the regular Mini Series uses mechanical parts while the Mini-E uses thermostatic. Both models for a particular size produce the same performance numbers so for the sake of brevity we will combine them in this review.
If you are trying to stick to a tight budget and only need the smallest of water heating performance, then the Mini 2-1 or Mini –E 2-1 should be on your radar. These units only produces 1.8kW of heating power thanks to its mobile 120V motor. This results in a water temperature range that goes from 86F up to 122F. Your flow rate will be limited, however. The activation flow rate is around 0.21 GPM and tops out at 0.4 GPM with an approximately 40F temperature rise.
Many people after hand-washing station solutions or other Point of Use applications will need something a little more capable. You can progress your way up the Mini Tankless Electric Water Heater product tree until you end up at the largest unit, the Mini 6-2.
The Mini 6-2 is actually powerful enough to be plumbed into two sinks at once. This is possible because of its larger 5.7kW heating source. This allows for the maximum flow rate to be increased up to over 2 GPM. Specifically, you will achieve around a 40F temperature rise at 1 GPM and if you decide to bump up the flow rate to 2.0 GPM, it drops down to a 20F temperature rise.
Next up is Stiebel Eltron’s larger electric Point of Use units, the DHC Series. These models find a happy medium between the smaller models that are designed mostly for handwash stations and the larger models that are capable of handling multiple bathrooms. There are quite a few models that scale up in power so you are sure to find one that meets your specific needs.
Starting off is the DHC 3-1. This model incorporates a 3kW heating element with a minimum water activation rate of 0.32 GPM. It is designed to optimally flow anything from 0.5 GPM up to 2 GPM and has a temperature rise of 40F and 10F, respectively.
There are larger 3-series models and things progress into 4, 5, 6, 8, 9, and finally the 10-series model. The largest of these water heaters, the Stiebel Eltron DHC 10-2, has a robust 9.6kW heating source. Due to its much larger size, it is capable of meeting the heating needs of two showers, two bathtubs, or two other similar types of applications. You will also see a bump in heating ability. At 1.0 GPM there is a 65F max temperature rise and at 2.0 GPM there is a 34F max temperature rise.
Finally come the largest residential models. It is worth mentioning that Stiebel Eltron has sort of combined two different series into one. The Tempra Water Heaters are designed primarily for whole-house applications and the DHC Series, while offering very similar power output, are more intended for commercial applications due to their different voltage and power series requirements.
So we will be focusing on the Tempra models in this review. There are actually two different types of Tempra models for a given power output but the differences lie in features which we will discuss in the next section. In terms of power output, there are six tiers beginning with the Tempra 12.
The Tempra 12 is capable of up to 12 kW of heating power via its 240V motor. With a minimum water activation flow rate of 0.37 GPM, it will produce a maximum temperature rise of 54F at 1.50 GPM and 27F at 3.0 GPM. This is powerful enough to handle most smaller apartments or homes with a single bathroom.
For larger homes, you will want to go with one of the larger models. For instance, if you have a 3 or 4-bathroom home then our best bet is going with the top-of-the-line model, the Tempra 36.
The Tempra 36 utilizes an impressive 36kW heat element. This huge heat source allows for a 92F temperature rise at 2.25 GPM and a 55F temperature rise at 4.5 GPM. This is some serious heating power that should have no problems with all but the very largest of homes.
Features –
There are some really helpful features available on every size and model of Stiebel Eltron tankless water heater. As is typical of most other manufacturers, specific features will vary depending on which unit you go with. So we will break down some of the most notable features from each.
The mini water heaters come with a simple flow switch that controls flow and they are equipped with a safety high limit flow guard as well as a manual reset option. And while the temperature is set to 100F from the factory, you can request for a factory adjustment to another temperature if desired. Its efficient operation comes thanks to Advanced Direct Coil Technology, a staple in the Stiebel Eltron product family.
The larger DHC tankless water heaters build upon the Mini lineup and add some features of their own. There is a more advanced flow switch that stops dry firing and premature failing from occurring. There is also a high-limit guard and manual reset similar to the Minis. And the heat elements are made of quality copper. Since these are typically used in Point of Use applications, they are shipped with a flow reducer that will fit on most faucets.
Finally, the impressive Tempra units tap into the most features. Depending on if you go with the base or the plus model, you will have a great digital interface with all of the customization options that you would need right at your fingertips. In addition, you will have seismic resistance, a maximum temperature safety limiter, constant temperature output thanks to Stiebel Eltron’s Smart Microprocessor Technology, and self-modulating output technology. And getting more into performance: The Tempra Advanced Flow Control is a patented process that works by reducing water flow by delivering the correct temperature of water rather than delivering hot water and then having to “offset” it by mixing it in with cold.
And while we didn’t get much into it in this review, other models will utilize some really cool features. Geothermal, solar, and a host of supporting features and accessories are present depending on the specific model that you go with.
Reliability –
Stiebel Eltrons tankless water heaters are another one of the industry-leaders when it comes to reliability. As we have discussed in the features section above, there are plenty of safety features in place to make sure that you don’t operate the heater outside of safe parameters but there is also a lot of care that goes into the manufacturing and assembly process. Premium materials are used including copper for the heat exchangers and stainless steel for protection.
And you will find a solid warranty. There is a 3-year warranty on parts and a 7-year warranty on leakage. There are some longer warranties out there but we have not seen any major issues with these units even after 5+ years so there is no major cause for concern.
Cost –
Overall, the price will vary quite a bit depending on the size model that you go with. However, they tend to fall into the higher end of the price spectrum compared to other water heaters on the market. But as we have said time and time again on this Ultimate Guide, we see nothing wrong with spending a bit extra to enjoy a unit that operates more efficiently and for longer periods of time.
Overall Rating –
We are quite impressed with Stiebel Eltrons tankless water heaters. Their large selection hits every target market and there are also quite a few additional units that weren’t discussed in this review that approach heating water in some really unique ways. As for the models we reviewed, all provided great performance for their size and they came with some helpful features that make the most of their heating ability. Another bright point is the build quality which is among the best in the industry. If you are in the market for a higher-end water heater, then definitely add this company to your list.
Takagi Tankless Water Heater Review
Models: T-KJr2/U, T-H3M, T-K4/U, T-D2/U, T-H3J, T-H3S, T-H3, T-M32, T-M50
Performance –
Takagi aims to be the go-to tankless water heater for your home and its lineup of products reinforce that. Since they don’t offer smaller point-of-use models, Takagi is going to be designed to handle anywhere from 1 to 6 showers depending on the specific model and the climate that you live in.
Starting with the lowest-end model, the T-KJr2/U, you will enjoy 140,000 BTU/Hr of heating performance in either gas-fired propane or natural gas forms. Using its proven copper heat exchange, you will have a UEF of 0.79. This is by no means industry-leading but it isn’t terrible, either. It will be able to comfortably support 1 shower in cold climates and 2 showers in warm climates. And this translates to a water temperature rise of 30F at 6.6 gallons per minute or 100F at 2.3 gallons per minute.
But let’s face it: most people have more than one shower in their home. Takagi has you covered there. A good model for a typical 3 shower home is the T-H3 and its 180,000 BTU/Hr heat source. With a max flow rate of 8 gallons/minute, it offers more than enough flow for most people’s needs. And this produces 3.8 gallons per minute of 100F temperature rise water.
And for those who want the absolute best that Takagi has to offer: look no further than the T-M50 series. It comes with a whopping 380,000 BTU/Hr and is really designed for commercial and industrial applications. But it can really move some hot water! It has up to 14.5 gallons/minute flow rate and can produce an impressive 6.1 gallons per minute with a 100F temperature rise.
Features –
Takagi tankless water heaters aren’t adorned with countless features like some of the more expensive units that we have tested, but they are no slouches, either. All models take advantage of commercial-grade copper which is up to 25x better at heat transfer than typical stainless steel. You will also find a secondary heat exchanger (made of steel) that handles corrosion better, prolonging the life of the unit. There are a variety of safety features included as well: freeze protection, overheat protection, surge protection, and troubleshooting code readouts to name a few.
As you move up in product size, you will enjoy a few additional features. This includes things such as remote controls, integrated controls built into the face, LED temperature display, and more.
As we discussed above, Takagi tankless water heaters aren’t industry-leading when it comes to efficiency. Because of this, you won’t find some of the more advanced and exotic features that other brands have that bump the UEF to 0.90 and above. However, that does result in some cost savings up front.
Reliability –
Takagi’s relatively simple approach and proven construction results in a rock-solid product. We have heard nothing but positives about the reliability of all of these water heaters. And the warranty reflects that: 5 years on the parts and a whopping 15 years on the heat exchangers. This is among the longest warranties in the industry.
Cost –
Another reason why these water heaters are so popular is their reasonable prices. While they aren’t super budget items, Takagi has found a happy medium between price and performance. Their units tend to be noticeably more affordable than a lot of the other premium water heater brands for a given power output.
The way that they achieve this is by taking out some of the more exotic features you may find in other brand’s models. This can affect things such as overall efficiency and user flexibility, but for many, that is a sacrifice that they are willing to pay to save what can be some significant money.
Overall Rating –
Takagi tankless water heaters provide us with a proven lineup of models designed to heat anywhere from 1 to 6 showers. This makes them a go-to brand for anybody looking to equip their home with either on a new build or during a renovation. You will enjoy solid power output and great reliability. And while you won’t find any hyper-efficient units that other brands offer, these are also quite a bit cheaper. All in all, this is a solid buy for someone who is a bit more money-conscious.
Thermoflow Tankless Water Heater Review
Models: Elex 5.5, Elex 12, Elex 24
Performance –
There are three different units to choose from and all 3 perform in a very similar manner. They all utilize electric-based heating elements. In addition, the two large models also have a self-modulating function that helps to improve performance.
The smallest model, the Elex 5.5, comes with a 5.5kW heating element. Depending on the inlet water temperature, this can be strong enough to handle anywhere from 1 to 3 sinks (although we recommend sticking to 1 or 2 if possible). We couldn’t find any information on specific heat rises for a given flow rate but, from experience, a water heater with this small of a heat source won’t make very impressive numbers.
The Elex 12 scales up to a 12kW heater and, as you might expect, the Elex 24 tops out with a 24kW heater.
As we mentioned above, the 24kW model will come with self-modulating technology that helps to improve efficiency by up to 60% compared to other non-optimized electric water heaters on the market. There is also a bit more flexibility in the temperature range: you can adjust it to be from 32F all the way up to 167F. With the added power, you also will have a much higher flow rate. You will be able to handle the needs of anywhere from 2 to 3 bathrooms with Elex 24.
Features –
Being a more budget-minded model, you won’t find just a ton of features here. The self-modulating technology is probably the most notable. There is also a smart LED touch screen with adjustable buttons and a temperature display. For safety, there is anti-dry protection and instant heating. This isn’t really a feature, but we do appreciate the very compact design of all the models. This makes them much easier to transport and install in tight areas of your home.
Reliability –
The overall build quality isn’t that bad. The electrical components seem to be in order and extra things such as being IPX24 waterproof help to prolong the life expectancy. We have heard some complaints about certain units not properly heating to full capacity over time. This might have to do with the heating element going out or it may be another reason: further elaboration from the manufacturer would be necessary. In addition, you won’t find the extremely long warranty that other more expensive models offer.
Cost –
If you are on a tight budget, Thermoflow tankless water heaters will definitely catch your interest. They are quite affordable when compared to other models at similar power levels. But you pay for this lower cost by the lack of features and shorter warranty period.
Overall Rating –
Thermoflow has a small lineup of water heaters that are designed for anything from a single sink up to a few bathrooms. However, their capabilities will be limited due to not being able to push as much water as larger units. Your climate will also play a big role in whether or not one of these will do the trick. There aren’t a ton of features but this results in a very reasonable asking price
Titan Tankless Water Heater Review
Models: N-10, N-42, N-64, N-75, N-85, N-100, N-120, N-160
Performance –
The main model lineup, the Titan SCR2, takes inspiration from the classic Titan ATC water heaters. Be incorporating more up-to-date technology, the result is a fast and more accurate heater with improved efficiency.
Starting at the bottom, you will find the Titan N-10. It is designed for small sinks or lavatories and is not recommended for more demanding applications such as showers or baths. It comes with a 3.2kW electric heater which is good for a 26F temperature rise at 1.0GPM and a 14F temperature rise at 2.0 GPM. It is intended for warm climates only.
From here you can move up to larger units such as the N-42, N-64, etc. The N-75 is a good “middle of the road” option thanks to its 7.5kW heat source. This is strong enough for more demanding Point of Use applications including washing machines, dishwashers, etc.
If you are after something that is powerful enough to heat the water for an entire average-sized home, then the SCR2 N-120 is the answer. It has 11.8kW of maximum heating power which is good for a 40F temperature rise at 2.0 GPM and a 20F temperature rise at 4.0 GPM.
If you need something even more powerful, then look into the recently-released SCR3 lineup. This seems to be the next generation of Titan water heaters and incorporates some new features along with its much larger heater. You can enjoy up to 16kW of heating power which makes it strong enough to heat even most large size homes in warm climates. It can heat 2.0 GPM of water for 55 degrees Fahrenheit and 4.0 GPM by 27 degrees Fahrenheit.
Features –
The SCR2 models have a few features worth mentioning. It comes with an updated sampling system that is not only faster but also more accurate. This allows for faster fine adjustments to water temperature which allows for efficiency gains of up to 60%. In addition to this, there is a manually resettable thermostat and an air/water deferential analyzing system that helps to prevent dry starts from occurring. The heating elements are made of Incoloy and cased in a copper/brass mixture which improves performance and also helps with life expectancy.
The SCR3 model (currently the N-160) introduces a new digital control interface with LCD screen. This makes reading and adjusting the temperature much easier. It also has self-diagnostic capabilities built in.
Reliability –
Titan tankless water heaters are tough cookies. We really like the care that went into designing the heating elements. The usage of high-end materials such as Incoloy, brass, and copper means that you will get the maximum life out of these parts. The built-in safety measures also mean that you will always operate these units within the accepted parameters which put less strain on the various components.
As for the warranty, it is just alright. You will have a 1-year limited warranty on components and a 10-year warranty on the casing. We have seen quite a few other companies offer 3 and even 5-year warranties on their parts so we feel that Titan should consider bumping this up if they want to attract some more potential buyers.
Cost –
Titan water heaters are situated in a price point that makes them affordable for most people. These certainly aren’t cheap units but they will outperform most of these “cheap” units that you will come across. In addition to this, their efficiency, features, and warranty is a bit less than other, more expensive, models that we have reviewed.
Overall Rating –
We are overall content with what Titan has to offer. Their electric water heaters are diverse enough to meet the demands of most people. Whether you are after a small Point of Use solution for a single sink or need a heater large enough to take care of a medium or large home, there is a product that will check off the boxes. There are a few areas that Titan could improve upon: a few more features would be nice and a bump up in their warranty for starters. But the asking price, considering what you get, is fair.
Vevor Tankless Water Heater Review
Models: 10L, 12L, 16L, 18L
Performance –
All Vevor water heaters are powered by the same 36Kw heat source that runs off of liquid nitrogen gas. This is actually a quite large heater, producing up to 4.8 GPM of hot water. Vevor doesn’t provide heat flow data (or at least we couldn’t find it) so we can’t give you specific numbers, unfortunately. However, from personal experience, we can say that a unit with this much wattage should be able to handle the needs of most small to mid-sized homes in a warm climate.
It is worth noting that customers have complained that heated water tops out at around 1 GPM. At this rate, you will be very limited in what you can use it for. So if you plan on running particularly hot water or live in a cold climate, then you may need to double up on this unit or go with a more powerful one from another company.
Features –
There aren’t a lot of features to get excited about here. Being a budget model, Vevor didn’t go crazy with exotic features and special settings. There are a set of knobs (water regular, gas regulator, and season setting) and also a LED display screen that shows the current temperature. Furthermore, there is instant electric ignition thanks to the battery-powered igniter. And for safety features, you will find over heat and over water protection. But missing are some of the more advanced calibration settings that adjust water flow and temperature and drive up efficiency. Because of this, a Vevor tankless water heater won’t run quite as efficiently as other, more expensive, models that we have tested.
Reliability – 
There have been a lot of complaints with these models. First, the tank is known be faulty. It will go out very quickly and require replacement. In addition, there are various fittings and connections that are missing and that you will have to source out yourself. Finally, there is little in the way of a warranty and the distributor is very bad about getting back to you in regards to replacement parts or repairs.
Cost –
We can’t deny that these are extremely affordable water heaters. And, on paper, the amount of hot water that they should produce makes them a great value. But as you can see above, there are some major concerns surrounding the actual water output when heating up the water very high in addition to various quality issues.
Overall Rating –
While we are all for great value products, Vevor’s small lineup of tankless water heaters falls a bit short. Their hot water output is lackluster, making them not good for much more than a couple of Point of Use applications unless you live in an extremely warm climate. Furthermore, there aren’t many features so the operating efficiency will be much lower than you would like. Finally, there are some major quality concerns. We recommend saving up a bit more and getting a product that will work as intended and have a much longer life.
WiseWater Tankless Water Heater Review
Models: XFJ80FDCH, XFJ100FDCH, XFJ120FDCH, XFJ150FDCH, XFJ180FDCH, SFJ210FDCH
Performance –
All of WiseWater’s water heaters are designed for larger applications. They come in both electric and gas models and we will briefly go over each.
There are three electric models: the 11Kw, 18Kw, and 27Kw. The smallest unit, the 11Kw, is designed for two points of use at the same time. Anything more than this, particularly in a cold climate, may struggle. It has a temperature range of 86F up to 125F and at a 2.0 GPM flow rate you can expect a temperature rise of around 2GPM.
This scales up to the largest electric unit which comes in at an impressive 27kW. It has the same 86F to 125F water temperature range but is capable of 4.5 GPM of water flow with a 40F temperature rise. This makes it powerful enough to sustain water for 2 to 3 normal bathrooms.
Similar to the electric choices, there are also three gas choices. We will be focusing on the largest two models that come in with 150,000 and 180,000 Btu/Hr of heating via propane. These are both larger water heaters and are suited for multiple bathrooms. The 150,000 BTU/Hr unit can pump up to 6.24 GPM and the 180,000 BTU/Hr models go up to 7.38 GPM.
Features –
These are very barebones units. You won’t find fancy touch screens, LED interfaces, or an array of custom settings. In addition, some of the more advanced self-modulating features found on other heaters we have tested are nowhere to be seen here. These are simple in design which hurts efficiency but also drops down the asking price. The only features really worth mentioning is the remote and the window on the side that displays codes to shows its working condition during annual inspections.
Reliability –
We don’t have a lot of long-term experience with WiseWater tankless water heaters so we can’t confidently state their reliability. However, they do come with a 3-year limited warranty which isn’t too shabby.
Cost –
WiseWater units, for the power output, are very reasonably priced. Most other companies that have this kind of power output are asking much more for their heaters. That being said, these are pretty simple in design and don’t come with a lot of features. And the performance, while good, won’t live up to the high-efficiency numbers other models with more advanced features have. Still, for many on a tight budget, this is a perfectly acceptable compromise.
Overall Rating –
We don’t have a lot of experience with WiseWater water heaters so we will hold off on a demonstrative judgment one way or the other. On paper, they put out good numbers and their asking prices are quite attractive. However, they do lack quite a few features that we like to see. We hope to have more experience with this company in the future so that we can update this review.
Zinnor Tankless Water Heater Review
Models: 6L electric, 8L electric
Performance –
You won’t find a lot of performance in these water heaters. The 6L unit is powered by liquid propane running at 1800 pascals. This doesn’t produce much in the way of heat or water flow. At most, you will want to use this model for a sink or small shower.
The other model, the 8L electric, comes with a 1500W heat element. You can adjust the output temperature between 55C and 75C but the water flow is severely limited as your crank it up. This model is best used in warm climates and for strictly Point of Use tasks.
Features –
Zinnor tankless water heaters are simple in design and don’t have a lot in the way of features. There are three simple knobs on the gas model and one knob on the electric model that will control heat and flow output. The gas model also has a temperature display (which we appreciate) but this is noticeably missing on the electric unit. Beyond that, there isn’t much to discuss outside of their mobility.
Reliability –
We haven’t heard any major complaints about the build quality here. We suspect that Zinnor has these brought in for a third party manufacturer so you always have to be cautious about those. In addition, the warranty is lackluster at best. But for this price point, we think that this is a risk worth taking if you are just after something low-cost and simple.
Cost –
It appears that Zinnor’s bread and butter come in selling very cheap products. The price you pay for this (outside of the money, of course) is that these products will typically not have the level of performance, features, or build quality that more expensive units will have. That is also the case here.
Overall Rating –
We weren’t really blown away by the small offering of tankless water heaters by Zinnor. The two models we tested did not produce impressive heat numbers and the lack of features was noticeable. But we understand that pushing the envelope isn’t really what these are intended to do. Instead, they are meant to be simple, low-cost solutions to people in warm climates who need a Point of Use water heater. And we suppose that they will suffice for that.
What are the Different Types of Tankless Water Heaters?
There are quite a few different types of tankless water heaters, and each comes with their unique pros and cons. We will briefly discuss some of the most popular ones in this section.
Electric Water Heater
Probably the most popular, an electric water heater receives its heat from an electric heat exchanger. These models are typically measured in kW (kilowatts). The benefit of these models is that you don’t have to run a gas line or have a gas tank attached to the heater for it to function. However, you may find that your energy bill is higher every month compared to a gas unit.
Natural Gas Water Heater
A natural gas water heater receives its heat ability from burning natural gas. The natural gas can be delivered either by a direct natural gas line or by a storage tank. Due to natural gas being very affordable, these units can oftentimes operate at much lower running costs than an electric unit (particularly in areas with electricity cost is high).
Propane Water Heater
A propane water heater functions in the same way as a natural gas water heater. Certain models will run off of gas propane while others will burn liquid propane. Many models will come with a propane unit and a natural gas unit that has essentially the same maximum performance (minimum performance may vary slightly). So if you are set on going with a gas tankless water heater then go with whichever type of gas is more affordable and that you have easier access to.
Hybrid Gas Water Heater
Certain models are designed to run off of either natural gas or propane. These allow for much greater flexibility but they do typically come at a slightly higher asking price as well.
Other Water Heater
There are a few special types of water heaters that receive their heat from other ways. They can include infrared, geothermal, solar, and a few others. But they are outliers and their performance relative to cost will typically be lower than the examples listed above. But we are all for new innovative ways to heat homes to come out!
Condensing vs. Non-Condensing Tankless Water Heaters
No matter what type of heat source you choose for your next tankless water heater, they nearly all operate in a similar manner (outside of the few outliers discussed in the section above). They either work through condensing or through non-condensing.
Non-condensing is the “old” style of water heater. They will use a standard heat exchanger which typically results in an energy factor of .82 to .86. The benefits of these units are that they are typically more affordable, extremely reliable (less moving parts), and there is a huge range of sizes and types to choose from. The cons are that they are not as efficient (higher energy bills each month) and the exhaust side of them will run much hotter.
Condensing is the 2nd generation of tankless water heaters. They incorporate a second heat exchanger. By adding a second heat exchanger, much of the heat that would normally go through your exhaust (resulting in lost efficiency and excess heat going through the exhaust) is re-routed through the second heat exchanger. This allows you to “tap in” to more of the heat and deliver to your incoming water supply. The obvious benefit of these models is that your efficiency goes up. It is common for condensing water heaters to have a UEF rating of 0.93 or more. The other benefit is that you don’t have nearly as hot as an exhaust. The cons are higher product costs, larger units, and typically a higher minimum water flow requirement.
There is also a third generation of water heater out now that is a hybrid. As we discussed above, one of the common issues with condensing water tanks is that they struggle with short draws and/or low water pressure. To offset this, these hybrid systems incorporate a small 1 or 2-gallon holding tank. This tank contains already hot water that can be used in short draw situations. The result is an even more efficient water heater with an optimal performance both in short and long draws. You can expect UEF ratings of 0.94 or more. The main drawbacks of these are their size, cost, and reliability. More components mean more areas that things can go wrong.
How Big of a Water Heater Do I Need?
A common question that we are asked is how big of a water heater does a home/bathroom/etc. need? Like many things in life, it varies.
First, let’s discuss how much water flow typical home fixtures need.
There is some variance, but you can expect a typical bathroom sink to flow around 0.5 GPM. A normal shower under full load will need around 1.5 GPM. And a kitchen sink with the faucet fully open can vary from 1.0 to 2.2 GPM. Things such as washing machines will vary much more. Depending on the specific wash cycle you are running as well as the technology in your washing machine (newer units run much more efficiently), you can expect anywhere from 1 to 2.2 GPM of hot water required. There is also the variable of the operation heat. A bathtub may typically operate at around 102F water temperature but washing machines and dishwashers commonly run anywhere from 110F up to 120F.
But that is just the first part of the story. The second part has to do with the actual temperature of the water (both coming in and coming out). We assumed around 105F water temperature in the paragraph above, but what about the water coming in?
Depending on where you live in the United States (or for our international friends, whatever local climate you experience), your average groundwater temperature will vary quite a bit. Also, the groundwater temperature will fluctuate throughout the year depending on the season. So a small water heater may fare much better when installed in say, Houston, compared to one that is running in Des Moines.
This can affect your tankless water heater in two ways: both in the water temperature it emits as well as the flow rate.
Above is a chart borrowed from Stiebel Eltron that shows some expected flow rates and their applications depending on water temperature as well as what type of Tempra model you are using. As you can tell, there is a lot of variances even for a single product when you alter the groundwater temperature.
The final piece of the puzzle has to do with individual home situations. Do you live in a busy household where it is common to have two showers, a dishwasher, and a washing machine running at the same time? Or are you a single guy/girl who doesn’t even run your dishwasher while you take a shower? This question will have a huge effect on your specific needs.
So putting all of this together, what do we come up with?
There are a lot of variables involved but a good rule of thumb for an “average” household is as follows:
- Count the number of full bathrooms that you have. Take this number and multiply by 1.5.
- Count the number of half bathrooms that you have. Take this number and multiply by .5.
- Count the number of kitchen sinks you have. Take this number and multiply by .25.
- Count the number of dishwashers you have. Take this number and multiply by 1.
- Count the number of washing machines that you have. Take this number and multiply by 1.5
- Add this number together
- Count the number of people that live in your home. For each person living in your home greater than 2, add 1 to the sum for 6.
For instance, let’s say that you live in a 3 bedroom, 2 and half bath home with 1 kitchen and 1 laundry room. 4 people live in the home (2 parents and 2 children). A rough estimate of the required flow rate that you would need is as follows:
- 2 full bathrooms x 1.5 = 3 GPM
- 1 half bathroom x 1 = 0.5 GPM
- 1 kitchen sink x .25 = 0.25 GPM
- 1 dishwasher x 1 = 1 GPM
- 1 washing machine x 1.5 = 1.5 GPM
- 3 + 0.5 + 0.25 + 1+ 1.5 = 6.75 GPM
- 2 additional people greater than 2 in the home = 6.75 + 2 = 8.75 GPM
So in summary, we recommend that the home above aim for a tankless water heater that can deliver at least 8.75 GPM of hot water (of around 105F).
Again, it is worth emphasizing that this is just a rough rule of thumb. If you live in an extreme climate (either hot or cold), have a huge family, or like to take super long hot showers then your specific results may vary.
Tankless vs. Tank Water Heaters
So we have discussed in detail about tankless water heaters, but what about tank water heaters? In this section, we briefly introduce tank water heaters and discuss their pros and cons relative to tankless models.
As the name suggests, tank water heaters contain a tank. This tank can vary in size but typically falls between 15 and 85 gallons. Inside this tank is already-heated water. Whenever hot water is removed for use, new cold water is introduced to the tank, at which point it is then constantly heated until it reaches what the temperature setting is set at.
A tank water heater has some benefits. First, the hot water that it contains, once heated, is ready to go. This means that a full and heated tank of water will probably outperform a smaller tankless water heater initially (obviously this is a different story if the tank is empty of hot water).
Next, tank water heaters are typically cheaper to buy. There is no need for exotic heat elements or fancy modulating technology. You simply heat the water and it is ready to go! Simple as that.
Finally, tank water heaters are cheaper to install. Installation costs can vary from 400 to 850 dollars.
There are some cons as well. First, tank water heaters are quite large. Having to carry around an 80-gallon tank adds to the size and weight of the unit.
Next, they aren’t nearly as efficient. Since you are constantly applying heat to the water, you waste a lot of energy heated up already heated water. This will impact your energy bill each month by 60% or more in certain cases.
Furthermore, once the hot water is gone, you have to wait much longer periods to have more hot water.
Another negative is that their life expectancy is shorter than that of a tankless water heater. You can expect an operation life to be between 8 to 12 years of typical use.
Finally, there are additional maintenance steps and concerns such as sediment buildup and the risk of leaks and potential water damage from storing such a large volume of hot water.
You are likely already very familiar with tankless water heaters from this review, but we will directly compare their pros and cons to tank water heaters.
The obvious pros are a smaller size, “unlimited” hot water (assuming that you operate within the flow requirements), and better efficiency. This is all thanks to a tankless water heater’s ability to heat water in real-time and not store hot water that is not being actively used. This will help to save money on your energy bill each month.
In addition to this, tankless water heaters don’t have to deal with sediment build-up or deal with the risk of storing large volumes of hot water in a container that could potentially leak.
Finally, tankless water heaters also have a longer typical operation life. A quality unit can last for 15 to 20 years.
But this type of water heater isn’t without their problems, either.
Tankless water heaters almost always cost more money. Some of the larger higher-end models can run well into the thousands of dollars.
Next, the “unlimited water” comes with a caveat. If you plan to push your water heater past a certain limit, it simply won’t be able to produce the hot water that you are looking for. This is in contrast to a tank water heater which, while hot water is present, can output in just about any rate that you would like.
Finally, a tankless model will have to deal with the many variables that we mentioned above regarding its performance. So a model that worked for your Aunt Lindy from Florida may produce different models for you if you live in North Dakota.
Contents
- 1 The Best Tankless Water Heater Reviews for 2020
- 1.1 Best Tankless Water Heaters – Top 5 Picks
- 1.2 The Competition
- 1.2.1 American Standard
- 1.2.2 Aquah
- 1.2.3 Assortit
- 1.2.4 Atmor
- 1.2.5 Bosch
- 1.2.6 Camplux
- 1.2.7 Chronomite
- 1.2.8 Denshine
- 1.2.9 Dltsli
- 1.2.10 EccoTemp
- 1.2.11 EcoSmart
- 1.2.12 Eemax
- 1.2.13 Excel
- 1.2.14 EZ Tankless
- 1.2.15 Gasland
- 1.2.16 iHeat Tankless
- 1.2.17 Lotus
- 1.2.18 Marey
- 1.2.19 Navien
- 1.2.20 Noritz
- 1.2.21 Rheem
- 1.2.22 Ridgeyard
- 1.2.23 Rinnai
- 1.2.24 SioGreen
- 1.2.25 Stiebel Eltron
- 1.2.26 Takagi
- 1.2.27 Thermoflow
- 1.2.28 Titan
- 1.2.29 Vevor
- 1.2.30 WiseWater
- 1.2.31 Zinnor
- 1.3 Rating Metrics
- 1.4 Full Reviews
- 1.4.1 American Standard Tankless Water Heater Review
- 1.4.2 AQUAH Tankless Water Heater Review
- 1.4.3 Assortit Tankless Water Heater Review
- 1.4.4 Atmor Tankless Water Heater Review
- 1.4.5 Bosch Tankless Water Heater Review
- 1.4.6 Camplux Tankless Water Heater Review
- 1.4.7 Chronomite Tankless Water Heater Review
- 1.4.8 Denshine Tankless Water Heater Review
- 1.4.9 Dltsli Tankless Water Heater Review
- 1.4.10 EccoTemp Tankless Water Heater Review
- 1.4.11 EcoSmart Tankless Water Heater Review
- 1.4.12 Eemax Tankless Water Heater Review
- 1.4.13 Excel Tankless Water Heater Review
- 1.4.14 EZ Tankless Tankless Water Heater Review
- 1.4.15 Gasland Tankless Water Heater Review
- 1.4.16 iHeat Tankless Tankless Water Heater Review
- 1.4.17 Lotus Tankless Water Heater Review
- 1.4.18 Marey Tankless Water Heater Review
- 1.4.19 Navien Tankless Water Heater Review
- 1.4.20 Noritz Tankless Water Heater Review
- 1.4.21 Rheem Tankless Water Heater Review
- 1.4.22 Ridgeyard Tankless Water Heater Review
- 1.4.23 Rinnai Tankless Water Heater Review
- 1.4.24 SioGreen Tankless Water Heater Review
- 1.4.25 Stiebel Eltron Tankless Water Heater Review
- 1.4.26 Takagi Tankless Water Heater Review
- 1.4.27 Thermoflow Tankless Water Heater Review
- 1.4.28 Titan Tankless Water Heater Review
- 1.4.29 Vevor Tankless Water Heater Review
- 1.4.30 WiseWater Tankless Water Heater Review
- 1.4.31 Zinnor Tankless Water Heater Review
- 1.5 What are the Different Types of Tankless Water Heaters?
- 1.6 Condensing vs. Non-Condensing Tankless Water Heaters
- 1.7 How Big of a Water Heater Do I Need?
- 1.8 Tankless vs. Tank Water Heaters