6 Best Tankless Water Heater Brands on the Market- Our Review

Water heaters are the most commonly used heater in our daily life, no matter for taking a bath or doing laundry, hot water is needed. Prices of tankless water heaters are not a small deal, therefore, when buying a heater, you need to get the best one for your dollar. So, here is our best tankless water heater brands reviews.  

There are many great brands, models and manufacturers that produce better electric heaters and some that produce better has heaters. So, we will break down these different types into electric, natural, LP and overall.

Here we go…..

6 Best Tankless Water Heater Brands Overview

In the tankless water heater market, there are many types of brands you can choose, picking a suitable and trustful tankless water heater brand will reduce many future problems.

After testing and listening to customer reviews, we narrowed it down to 6 best tankless water heater brands for you. They are experts in either quality or working performance. You can choose one according to your actual needs.

1. Navien

Navien tankless water heaters are perhaps the most expensive one among tankless water heaters market in 2021. Two series of products are included, they are NPE-A and NPE-S.

NPE-A refers to NPE-Advanced series, many advanced technologies are included in tankless water heaters, such as ComfortFlow technology, HotButton design as well as NaviLink add-on, but the most worth mentioning feature of it is built in re-circulation pump and buffer tank.

NPE-S, on the other hand, refers to the NPE-Standard series. It means all the Navien tankless water heaters of this series meet the national standard and have excellent working performance. They are a condensing type, which means less energy is wasted in the heating process, which saves on heating bills for you.

The best selling types of these tankless heaters are 110A, 180A, 240A and 110S, 180S as well as 240S Navien tankless natural gas tankless hot water heaters. We have made detailed reviews for each type, if you have the interest, please feel free to check the reviews, or to get more information on the official website of Navien.

hot water heater brands

2. EcoSmart

EcoSmart tankless water heaters are brilliant in their small and simple shape, uniquely  designed as compact shape, they are still available to be used as whole-house tankless water heaters.

One feature of EcoSmart tankless water heater is its patented self-modulating technology, it heats water when you use and saves energy. Also, it is designed to activate at 25 GPM, far lower than normal tankless water heaters. And the Flow Sensor Technology modulates the consumption to meet the demand for hot water.

The hot-selling EcoSmart tankless water heaters include Eco-27, Eco-36, Eco-18, and Eco-11 series tankless hot water heaters. All of them are designed simply to install and operate. Unlike other tankless water heaters brands, EcoSmart promises to provide limited lifelong warranty for heating exchangers.

All the top and best EcoSmart tankless water heaters are introduced in detail in EcoSmart tankless water heaters reviews we have made. Please feel free to get more information there. Besides, if you have more interest in the brand, you can also get to their official website for more info. And all the top-selling and recommended tankless water heaters of EcoSmart can be found on Amazon directly.

tankless water heater brands

3. Rinnai

Rinnai is also one of the leading tankless water heater brands on the world market. It is a Japanese brand and first produced high efficient tankless water heater in 1964. Rinnai America is founded because of the hot demand for its products in North America, and successfully passed the standard of ANSI. ( American National Standards Institute)

Rinnai tankless water heaters are suitable to be used for the whole house and commercial. Most of the tankless water heaters of it are over 9 gallons per minute, perfect for providing endless hot water for you. And is capable enough to support multiple bathroom use.

Top selling Rinnai tankless hot water heaters include RUC98i, NRL94eP, and RL75iN series, etc. They are all large capacity tankless water heaters, and the temperature range of residential is up to 140 degrees F, while commercial can reach as high as 160 degrees F. Quiet heating brings the most satisfying user experience in both bathing, showering or washing dishes or washing clothes.

We made detailed reviews on Rinnai tankless hot water heaters and also picked 8 best water heaters for you to choose, each of them has different performance and capacity, but are all excellent working performers. Just feel free to check for more information. Or you can step to Rinnai official website and find more suitable tankless water heaters for you. If you are leaning towards one, please check out the pricing on Amazon, there are often deals to help you save money.

best brand tankless water heater

4. Rheem

If you never heard of Rheem then you haven’t researched water heaters. Rheem tankless water heater prices are relatively affordable and cheap compared with other brands. But not to be fooled by its price, the performance of it is praised as the top one by customers.

The design of Rheem tankless water heaters are also simple and compact, you can easily hook it up in your bathroom, and it occupies only a small space. The heating speed is fast, that you can be up to desired heat in about 15 seconds, greatly reduced the waiting time, and can save large water costs for you.

RET-13, RET-18, and RTG-95XLN, as well as RTG-64XLN series, are top-selling products of Rheem. Among all the tankless water heater brands, Rheem is the one that excells in both electric water heaters and natural gas water heaters. And nearly all of which are high energy-efficient units and are designed for longevity.

We made detailed reviews on the best Rheem tankless water heaters, please feel free to check it out. If you have any inquiries about any other problems, you can get to the official website of Rheem or contact us for more information. Besides, all four recommended Rheem tankless water heaters we ranked are sold on Amazon, you can freely check for the updated price on it.

best water heater brand

5. Noritz

Noritz tankless hot water heaters are mostly stainless steel heating exchangers. Some are stainless steel and copper both, giving you more options. It is a brand dedicated to producing high energy efficient residential and commercial tankless water heaters.

They are designed simple but with large capacity, most of which are able to support multiple bathrooms or larger homes use simultaneously. As Noritz produced a large sum of natural gas and propane tankless water heaters, they specially make them low NOx design, thus very little amount of greenhouse gas is produced.

NRC661-DV-NG and NR981-SV-NG are on the top of the hot-selling list in 2020 on the market. High-quality copper wall and double exchangers give you more choice. A 93% energy rating saves you more money on your heating bills. Also, Noritz provides 12 years warranty for the heating parts, which is relatively long compared to other manufacturers.

If you want to learn more about the brand and quality put into the best Noritz tankless water heaters, we have made detailed reviews for you. You can also go to the official website of them, there will be technical staff to solve all your problems and questions for you. After getting the basic knowledge about the water heaters you want, just feel free to check on Amazon about the latest pricing.

different brands of tankless water heaters

6. Takagi

Takagi tankless water heaters are well known around the world, especially in the North American market. It is the only one who specialized in “tankless-only” products in America and is also the first to improve the thermal efficiency of up to 95%. It can be regarded as the most energy-efficient water heater available.

Many advanced technologies are adopted on Takagi tankless hot water heaters, which includes Air Fuel Ratio Sensor, freezing protection, Hi-limit switch and overheat cutoff fuse. All of them are used to keep safety first when using tankless water heaters.

T-KJr2-IN-LP, T-K4-IN-NG, and T-KJr2-OS-NG of their tankless water heaters are the top selling products on the market of 2020. They are powered mainly by natural gas and propane. Digital remote control makes it easy to use, large flow capacity meets the demand of multiple bathrooms uses or larger house use. The key feature of Takagi tankless water heaters is that it requires very little maintenance.

Price of Takagi tankless water heaters are on the higher end, but it totally is worth the price. If you have an interest in their products, please feel free to check the price on Amazon, frequent discounts on Amazon will help you save some money for you. Also, you can also find more information on Takagi official website.

best water heater brand to buy

All the six top tankless water heater brands we listed above are worth trusting in your home or business. There are still many other trustworthy tankless water heater brands on the market, as long as the heater fits your home and budget, check out more information on the best tankless water heater.


Best Natural Gas Tankless Water Heater Brands

Some tankless water heater brands excel in gas, while others dominate the electric ones. Here we picked several of the best gas tankless water heater brands that excel in this area for you to choose:

1. Rinnai tankless gas water heater

Most of Rinnai tankless gas water heaters have a large flow rate, reaching up to 9 gallons per minute, able to support use over 2 bathrooms simultaneously. And with the commercial temperature controller, it is able to meet the demand for commercial use as well.

The high thermal efficiency of Rinnai tankless gas water heaters make them energy efficient and save money on heating bills over the long haul. Outdoor air combustion makes it safe for many years.

Find more information on Rinnai tankless gas water heaters on Amazon

commercial tankless water heater reviews

2. Rheem tankless gas water heater

Being a gas tankless hot water heater, there must be venting kits installed along with the heater, so the fumes can be vented outside for safety. These Rheem designs of products are for outdoor installation , thus no venting kits are needed. It is a safer bet if you live in the right climate.

The low NOx design of the Rheem tankless gas water heater also helps reduce the creation of greenhouse gas emissions, thus protecting the environment. They are also more energy-efficient. Most Rheem tankless water heaters are also suitable for high altitude use. Get more information and the latest price on Amazon.

best outdoor propane tankless water heater

3. Eccotemp tankless gas water heater

Eccotemp is also known for producing a portable natural gas tankless water heaters, on the portable units the flow rate of it is quite small, around 3.5 gallons per minute, but as they are mostly used for travel or RV, the low flow rate can still meet the demand of basic needs for hot water.

They are capable of delivering hot water in just 5 seconds and are easy install. If you are learning toward getting a Eccotemp tankless water heater for large family use, you will find it as a wrong brand. But if you need to choose one that is portable, for or able to be used for camping or RVing, then this will be the best choice!

You can get more information on the Eccotemp official website for more information or new innovating in tankless gas water heaters. If you need more or curious about pricing, just feel free to check Eccotemp out on Amazon.

best indoor tankless water heaters

4. Takagi tankless gas water heater

Takagi is a tankless gas water heater brand that brings the use of high-tech capabilities for its products. The Air-Fuel ratio sensor is equipped on all of its products, used to maintain and monitor combustion all the time. The sensor allows the adjustment of the fan motor speed, ensuring that air and fuel have the perfect ratio. This proper mix also minimize gas emissions and improves efficiency greatly.

Compact size, but large water flow enables you to use it as a residential and or commercial tankless water heater. If you want to get more information or the updated pricing, please check the link Amazon.

best outdoor tankless water heater natural gas

5. Navien tankless gas water heater

Two main series of Navien tankless gas water heaters can be chosen, one is NPE-Standard series and the other is NPE-Advanced series. Both adopt condensing technology to reduce energy consumption and greenhouse gas. The condensing technology provides up to 0.97 UEF or 0.99 EF, this is highly energy efficient.

Ready-Link cascading technology enables you to cascade up to 16 units in a daisy chain mostly for commercial use. Also, common venting allows up to 8 units for one exhaust. An internal buffer tank and re-circulation pump keeps the water ready at temperature.

Navien tankless gas water heater price can be much higher than other brands, but it is probably the most energy-efficient brand and the heat performance as well is a quality totally worth the price. Check the latest price on Amazon if you have an interest in this most efficient brand.

indoor tankless water heater

6. Noritz tankless gas water heater

Noritz tankless gas water heater utilizes a low NOx design to reduce greenhouse emissions, stainless steel and copper heater cores give better longevity and thermal properties. Plus, more choices for venting. A high flow rate enables the support 2 or 3 bathrooms simultaneously.

Noritz tankless gas water heater thermal efficiency reaches as high as 93%, which means seldom fuel is wasted and one of the higher energy efficient brands. The heater is also made simple to operate and install. Not much high technology is adopted but is also trustworthy and reliable because of its quality level and no $20 parts to go bad making the whole thing useless.

So, based on the fact they use metal and design to create a high efficient rate means longevity with minimal to no maintenance.

If you have any interest in Noritz tankless gas water heaters, please check for more details about the products and prices on Amazon.

outdoor tankless gas water heater

Best Propane Tankless Water Heater Brands

The working principle and working condition of propane tankless water heater are quite the same as natural gas type. Some of the leading brands in the natural gas tankless water heaters also excel in propane heaters. Here we will suggest several best propane tankless water heater brands for you:

1. Navien propane tankless water heater

As we have recommended above, Navien adopts many advanced design and engineering principles on their products, especially the condensing technology, recovering extra heat that would be lost in non-condensing tankless water heaters to reduce energy consumption as well as carbon oxide emissions.

Our pick

2. Rinnai propane tankless water heater

Rinnai adopts low NOx design and reduce energy waste in the using process, the majority of propane gas is used without waste. Like Rinnai natural gas tankless water heaters, propane types of it is also widely praised. It can also be used for commercial use.

Best propane Rinnai

3. Takagi propane tankless water heater

Takagi propane tankless water heater are popular for its T-KJr2-IN-LP series. Large water temperature range and high flow rate enable it to support endless hot water for you in a medium to large house.

Most popular

Best Electric Tankless Hot Water Heater Brands

Electric tankless hot water heaters reduce the matter of installing ventilation kits and can be used anywhere you want, without worrying about the gas lines either. But choosing the wrong electric tankless water heater means you will most likely pay more money on electric bills and for maintenance.

best brand tankless water heater
Best tankless water heater brand

So we picked out several best electric tankless hot water heater brands for you to choose.

1. EcoSmart

EcoSmart is an expert in electric tankless water heaters, it adopts self-modulating technology to modulate consumption based on the demand for hot water. The small and compact shape of EcoSmart makes it easy for installing and using. Probably your best bet for point of use hot water.

Best midsize (2 baths) average

2. Stiebel

Stiebel electric tankless water heaters have large selection of sizes in its Tempra Plus series. It supports full power modulation and can be perfectly used for commercial. The built-in advanced control system is used to regulate water pressure automatically. Find more information on products and prices on Amazon if you have an interest.

This unit is best for the average 2 bath house in the middle of the USA ( incoming water about 50 degrees)

3. Bosch

Bosch electric tankless water heaters are mainly famous for their compact and portable shape, especially for mini-tank water heater, it can be installed directly under the sink for kitchen use. Fast recovery on hot water reduces waiting time . You can find more information on Amazon.

Perfect for point of use

the best water heater brand
best instant water heater brand

Tankless Water Heater Brand Comparison

Among so many tankless water heater brands on the market, you may get perplexed and puzzled about the exact difference between each brand and have no idea about which to choose. So, we helped compare tankless water heater brands for you as follows:

  • Navien vs Rinnai Tankless Water Heater Reviews

Navien and Rinnai are both leading brands on producing natural gas and propane tankless water heaters.


The average size of both Navien and Rinnai tankless water heaters are similar, weighing around 90 pounds and are middle size types. Navien adopts white as its main color, looks simple, and fits nearly all the decoration styles. On the other hand, hot selling Rinnai tankless water heaters are normally dark grey, with a more modern look.

Flow Rate 

The average flow rate of Navien is designed higher, reaching up to 8 or 9 gallons per minute, some are even 11 GPM, perfectly meeting the demand for large homes or commercial use. Rinnai tankless water heaters also have a large flow rate, topping out around 9.5 GPM. So if you want a large flow rate or large capacity tankless water heater, both brands can be a perfect choice.

Energy Efficiency  

The thermal efficiency of Navien tankless hot water heaters reaches up to 0.95 (95%), which is quite energy efficient. The hot-selling types of Rinnai tankless water heaters can also reach around 0.92 (92%), but for other series, average thermal efficiency is only 0.82 (82%) on Rinnai.


Both of Navien and Rinnai tankless water heaters are to the higher range, they average about $1,500. But the quality and performance of their products are well worth the price, if you lack the budget or only need a small flow rate tankless water heaters, you may check the other best brands.


Warranty time for heating exchanger is longer in Navien than in Rinnai, which promises 15 years free of defect warranty. And Rinnai only keeps a 5-year warranty on the unit.

  • Rinnai vs Rheem Tankless Water Heater

Rheem is a brand that produces both electric tankless water heaters and natural gas or propane tankless water heaters. And Rinnai excels on natural gas tankless water heaters only.


Rheem electric tankless water heaters are normally light, weighing no more than 10 pounds and occupying less space after installation. The natural gas tankless water heater of Rheem, however, weighs about 60 pounds, but still lighter than the Rinnai comparatively.

Flow Rate 

In terms of flow rate, Rinnai tankless water heaters range around 9 gallons per minute, while Rheem tankless water heaters only range around 8 gallons per minute.

Energy Efficiency  

The thermal efficiency of each tankless water heaters of Rinnai and Rheem differs a lot, some reach 94% while some only have 82%. Therefore, both of the two brands have similar energy efficiency on tankless water heaters.


If you lack a pocket full of twenties, then Rheem can be a perfect choice for you, most of Rheem tankless water heaters are $1000 or less and still have trustful brand performance. While the Rinnai tankless water heaters price come in around $1500.


Rheem promises a 10 year warranty on the heating exchangers, twice as long as a Rinnai.

best electric water heater brand
Best tankless water heater brand

So, Who Makes the Best Tankless Water Heater?

Overall best Brand results

  • Budget friendly: Rheem
  • Most efficient: Navien
  • Best warranty: Navien
  • Smallest footprint: Rinnai
  • Best point of use: Eccotemp-Bosch

After getting some knowledge on features of each tankless water heater brands, do you still have the question on what is the best tankless water heater brand? Or who makes the best tankless hot water heater?

Each tankless water heater brand has its own irreplaceable features and experts in one area, some of the features fit a small home, while others may be a factor that commercial heater needs to get. Therefore, on choosing the best tankless water heater brand, you still need to consider the actual feature of a particular tankless water heater for your individual needs.

On choosing, you need to know the size which is flow rate, temperature rise, applications, and installation method. And whether the tankless water heater is powered by electric, gas or propane, if the price of the machine suits your budget. All the considerations need to be taken and then you may find the most suitable one.

Of course, if you still have trouble finding the most suitable tankless water heaters, you can check detailed information on Amazon, or contact us directly.


David: Penn State-educated Mechanical Engineer and Business-savvy Fluid Dynamics Specialist. Balances family plumbing business support with a thriving engineering career at a top, undisclosed company. (they want it that way) I help Will with plumbing and HVAC needs on his Real Estate.

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