Best Tankless Water Heater Reviews 2019

Are you in search for the best tankless water heater? Heating water for various functions has currently become a basic need for each and every home. To serve this purpose individuals are now using water heaters which vary across different models and prices. One of the most widely used and best water heaters are tankless water heaters. They’re high power water heaters that heat water instantly in a very efficient manner. They don’t retain water internally. The heater is supplied with flow sensors that activate it once water travels through them. The water circulates through a device and is warmed by gas or electricity. They’re coated with sturdy coatings to shield them from acidic environments.

Best 5 Tankless Water Heater Comparison Chart

  • Stiebel Eltron Tempra 24 Plus Electric Tankless Water Heater

  • Dimensions - 21.5 x 19.5 x 8.8 inches
  • Voltage - 208-240V
  • Digital temperature control
  • Rinnai RL75iN Natural Gas Tankless Water Heater

  • Dimensions - 14 x 9.3 x 23 inches
  • BTU-10,300 - 180,000
  • Thermal Efficiency-82%
  • Takagi T-KJr2-IN-LP Indoor Tankless Water Heater

  • Dimensions - 28 x 17 x 10.5 inches
  • BTU- 140,000
  • 6.6 GPM max flow rate
  • Ecosmart ECO 36 36kw 240V Electric Tankless Water Heater

  • Dimensions - 17 x 19 x 3.8 inches
  • Voltage - 240V
  • Self Modulating Technology & digital temperature control
  • Rheem RTG-64DVLN Prestige Tankless Natural Gas Water Heater

  • Dimensions - 14 x 10 x 26 inches
  • Natural Gas
  • Direct Vent Indoor

Top 9 Tankless Water Heater Reviews

In comparison with typical water heaters, the tankless heaters guarantee vital energy value savings. The tankless water heaters run at a slow rate that’s by moving 2 to 5 gallons per minute. The advantages of some of the best rated Bosch tankless water heaters are that they operate only when there’s a requirement for warm water that helps in reducing energy prices. They’re very much reliable additionally. If the unit is sized properly, they effortlessly deliver never-ending supply of water at predetermined temperature levels. These storage tank scores high in safety. Their safety is as a result of the actual fact that they solely operate once the hot water is needed. Heating water for various functions has currently become a basic need for each and every home.


Stiebel Eltron Tempra 24 Plus Electric Tankless Whole House Water Heater

Tempra Plus

Specifications are: Voltage: 240 Wattage: 24 Amperage: 2×50 Min. required circuit breaker size: double pole 2×60 Recommended wire size: 2 x 6 Maximum temp. increase: 92 Weight: 15.4 Width: 16 5/8 Height: 14 1/2 Depth: 4 5/8 Working pressure: 150 PSI.

This water heater can be easily compared with the top quality Noritz electric tankless water heater. The features are built with advanced technology for providing better service to the users. It has digital temperature control system which helps in keeping a check on the temperature of the water being used in a simple way. The fundamental advantage is that for this kind of heaters, no venting is required which gives users a sigh of relief. The sleek design helps in solving space problem so it can be kept anywhere in a proper place. This whole house tankless water heater consumes very less power, so it saves our money at this part which is very much beneficial. The primary consideration for the buyer is to have an electrical service installed for it. Also, it can work at any range of temperature and provides unlimited hot water.


Rinnai RL75iN Natural Gas Tankless Water Heater, 7.5 Gallons Per Minute

RinnaiThis Rinnai tankless water heater is 58.4 pounds in weight and has dimensions of 14 x 9.3 x 23 inches. This set is ideal for two to three bathroom homes and can be the best tankless gas water heater available. It delivers up to 7.5 gallons of hot water per minute (GPM) and helps in saving energy and money.

It is ideal for two- to three-bathroom homes which is a beneficial feature and could be used as the commercial tankless water heater. The R75LSi delivers up to 7.5 gallons of hot water per minute (GPM) while saving energy and money. It requires special Rinnai vent. It comes standard with MC-91-1 US digital controller with error code indicator. Its thermal efficiency is 82% which is an advantageous feature of this product. Temperature variations are an important characteristic- Residential Temperature Settings: 98°F – 140°F and Commercial Temperature Settings: 98°F – 160°F. This model turns out to be the top model that has got advantageous features supported by superior technology. It offers great versatility in every field that is either residential or commercial. With a sleep and contemporary design that easily fits into the available space. You may read Rinnai tankless water heater reviews in detail on this site.


Takagi T-KJr2-IN-LP Indoor Tankless Water Heater, Propane


The capacity of this propane tankless water heater is for 1 to 2 bathrooms, and the flow rate is maximum with 6.6 GPM. Gas Inputs are 19,500 to 140,000 BTU per hour. Energy Factor Rating are 0.83. Inlet Gas Pressure – Min: 8.0″ W.C. / Max 14.0″ W.C. It’s dimensions are 20.3″ H x 13.8″ W x 6.7″ D. It provides direct vent capability. It provides an electric ignition facility. Takagi heaters can give tough competition to the top heaters like best quality Navien tankless water heaters.

This is the smallest water heater in the Takagi tankless line. This product is 38 pounds with product dimensions 28 x 17 x 10.5 inches. This is a powerful unit with gas inputs up to 140,000 BTU per hour – can meet all the hot-water needs of a small home or apartment with one or two bathrooms. This product is cost efficient and is environmentally friendly. This Takagi tankless water heater can be converted into a direct-vent unit by using the optional TV10 conversion kit for installation in a confined space. The unit has four preset temperatures on the unit are: 113°F, 122°F, 131°F, 140°F. To achieve any temperatures other than those presets, we require the TK-RE02 temperature controller. So its temperature settings are very much versatile.


Ecosmart ECO 36 36kw 240V Electric Tankless Water Heater


The ideal weight of the product is 17.4 pounds with product dimensions 17*19*3.8 inches with 240 volts technology and even no battery is required. This brand also provides a lifetime warranty for residential use.

This product is equipped with latest and advanced patented self-modulating technology. It is the largest electrical tankless water heater available. The beneficial feature is that the incoming water temperatures can reach as low as 37 degrees F. A digital temperature control allows us to set temperature in increments of 1 degree so that we can set the temperature to how we like it. The ECO 36 is the most powerful model from the full line of tankless water heaters, with the capacity to handle a large single-family home. It saves up to 50% on our water heating costs with most advanced feasters. It is unto 90% smaller so space availability is not a problem. The feature is that the product is eco-friendly so it is safer to use.


Rheem RTG-64DVLN Prestige Low NOx Indoor Direct Vent Condensing Tankless Natural Gas Water Heater

This product is designed for continuous hot water. It’s  specifications – 6.8 gal./min. at 35A-Degree F rise max. – 5.3 gal./min. at 45A-Degree F rise max. Best features: – New. 3-Inch/5-Inch Concentric Vent System with Integrated Condensate Collector.

It is 82% energy efficient with stainless steel condensing heat exchanger. It is equipped with intelligent electronic controls designed to increase energy efficiency and safety. The basic thing is that it is mostly used in industries. Hot start programming helps minimize fluctuation in water temperature, referred to as “cold water sandwich”, during periods of frequent on/off operation. So this top class Rheem tankless water heater provides reliability to the users by providing different temperature controls. It has a built-in electric blower. It is environmentally friendly with the ultra low NOx burner. Also, freeze protection is provided up to -30°F. Installation is quite easy with the use of the Rheem service kit which has a port for pressure valve. The good thing is that the beginner can easily get the heater mounted by serving simplified manual.


Bosch 330 PN LP Therm Tankless Water Heater, Propane

A Piezo push-button ignition operates the 330 PN LP Therm Tankless Water Heater by Bosch. A constant temperature at varying flow rates of water is maintained as the product has a modulating gas valve. It has a flow rate of 3.3 gallons per minute at 35F degree rise and has a thermal efficiency of more than 78%. The tankless system can be wall-mounted, is easy to install and does not require any batteries.

Bosch 940ESLP Tankless Water Heater

Key Features

The Bosch 330 PN is an ideal choice for small homes considering the following key features of the product:

  • The Piezo ignition system does not require any electrical connection
  • Has a max input of 75,000 (BTU)
  • Its thermal efficiency is rated above 78%
  • The unit has a capacity of 3.3 gallons per minute at 35F degree rise
  • Vents with galvanized B vent – natural draft
  • Product dimensions: 10.5 x 18.5 x 36.8 inches
  • Product weight: 24.6 pounds
  • Has an energy start certification
  • Has a warranty of 3 – 15 years depending on application
  • No batteries required for running the application

Our Review

  • It is easy to install and operate as the Piezo ignition system does not require any electrical connection.
  • The water flow does not fluctuate and holds a steady temperature even at full hot.
  • It is value for money as it easily caters to the needs of a small household and the next better product has an added price of $1,000.

  • The Bosch 330 PN is advertised and ideal for a single application only.
  • It requires a minimum of 6” vertical venting or the safety features shut the propane off, and the model cannot be used without venting to the outside with a 4” pipe.


Eccotemp 45HI-LP Horizontal Bundle

The Eccotemp 45HI-LP Horizontal Bundle is a tankless water heater that can be wall mounted and is compact and easy to fit in small spaces; though it is termed as the largest indoor model of Eccotemp tankless line. The 45HI-LP can fulfill the hot water requirements of a regular household with up to two bathrooms as it has a 6.8 GPM and 140,000 BTU per hour. It also can cater to small commercial units as it has a fully automated control system. Powered by liquid propane, the device is split system adaptable that can further enhance its efficiency and increase the speed of hot water delivery.

Key Features

The following key features make it a perfect choice for standard homes:

  • Digital remote with simple controls make it convenient and easy to operate.
  • 10-year warranty on heat exchanger ensures its long term durability.
  • 5-year warranty on parts makes it a cost effective option.
  • It has an energy rating of 82%.
  • Comes with a 110 volt UL listed power cord.
  • It is CSA certified for US and Canadian use.
  • Product dimensions and weight: 15”x5”x24” & 38lbs.
  • Hot water capacity range: 1.2 – 6.8 GPM.
  • Maximum/Minimum gas rate: 19,800 – 140,000 BTUs.

Our Review

  • Compact and wall mounted the device is easy to install and can be easily fitted in small spaces.
  • The digital remote with simple controls and diagnostics provides the convenience of use.

  • Though it is an indoor heater, it requires an exterior vent kit for operation.


Rheem RTG-84XLN 8.4 GPM Low NOx Outdoor Tankless Natural Gas Water Heater

The Rheem RTG-84XLN is a tankless water heater that is powered by natural gas. This model is for residential use only and ensures you do not run out of hot water. It is based on the new next generation burner technology and requires outdoor installation. It is easy to install in comparison to an indoor tankless heater and requires less space as no additional venting is necessary. The product efficiently caters to the requirements of a two bathroom household and is an energy efficient application that provides a continuous supply of hot water.

Key Features

The following key features make it an ideal solution for you to heat your water at home:

  • It is a natural gas tankless water heater
  • Needs to be installed outdoors only
  • Has a capacity of 8.4 gallons per minute at 35 degrees rise
  • The package includes a UMC – 117 remote control and 10 feet of thermostat wire
  • It is a low Nox version
  • Has an energy star certification
  • Does not require any batteries
  • Product dimensions: 14 x 10 x 26 inches
  • Product weight: 54 pounds

Our Review

  • The venting and unit in case of the Rheem RTG – 84XLN are one which makes the product compact and minimizes the space needed to install it.
  • The water stays consistently hot once the cold water has run out and provide hot water on demand.

  • Though the dimensions of the heater are compact, it requires a connection for water, gas and electrical supply.
  • There is an added expenditure for copper, gas line, electrical parts and other miscellaneous parts for the installation.


Takagi T-H3S-DV-N Condensing High Efficiency Natural Gas Indoor Tankless Water Heater, 8-Gallon Per Minute

Capable of catering to the hot water requirements of two bathrooms in colder climates the Takagi T-H3S-DV-N with gas inputs of 180,000 BTU is an ideal choice for standard homes. In warmer climates, it can even provide for the hot water needs of homes with three bathrooms. The tankless water heater runs on natural gas is designed for indoor use only and has computerized safety features. It has a temperature range of 100 – 140 degrees_celsius and a flow rate of 8 gallons per minute. The product is compact and can be installed in smaller spaces leading to space saving. It is easy to install and provides for on demand usage.

Takagi T-H3S-DV-N

Key Features:

The product is equipped with the following features that make it an ideal choice for regularly using in homes to meet its hot water needs:

  • Equipped with electronic safety features, no need to worry about pilot light
  • Satisfies the 2012 SCAQMD rule 1146.2 for ultra low NOx emissions
  • Has energy star certification
  • Does not require batteries
  • Is only for indoor usage
  • Has a temperature range of 100 – 140 degree_celsius
  • It has a flow rate of 8 gallons per minute
  • Product dimensions: 11.2 x 17.8 x 24.9 inches
  • Item weight: 66 pounds

Our Review

  • The heater is very easy to install on the whole.
  • It can produce enough hot water for two bathrooms in cold climates which make it an excellent choice for places that experience excessive cold.

  • Hooking up the neutralizer can sometimes be a time-consuming job.
  • Can be a little noisy at times when it fires up.

What Is The Best Tankless Water Heater

Tankless water heaters are now used at every place such as homes or business because of the increasing demand for this product. Due to the availability of a variety of products in the market different factors are required while choosing the best tankless water heater. So one should have in-depth knowledge about some of the best tankless water heater brands available in the market.

There are an endless number of brands to choose from and each is slightly different from the other in addition to the cost of the tankless water heater of different kinds and sorts. Some help in providing environment-friendly technology while others put their main focus on efficiency and power. So we should find a right brand matching our need.

Some of the points to be considered before buying a tankless water heater are-

  • Temperature Considerations – To make sure of getting a right sized unit, we need to figure out how cold the average temperature of the water is in our area so that we can easily find a product for that particular temperature. When the average temperature of our area is cold then the more stronger water heater is required.
  • Choosing A Proper Size– We should choose a proper size of the water heater to be used which is based on the requirement of a user. Many varieties are available in the market which provides water heaters with different capacities. So in this way, a right model for our need can be chosen.
  • Choosing Between The Source– If we live in a cold climate, we should use a natural gas or propane model as they are more powerful and efficient. If we live in a warm climate, we should use an electric tankless heater. If we are using gas or propane model, we need to make sure that our area has readily proper venting facility.
  • Decision Of The Maximum GPM – We need to make sure that we should never exceed the maximum gallons per minute {GPM} that our unit can produce. If there is a certain time of the day when a lot of water is being used, then we need to evaluate the GPM for that time of day.
  • Going Green – We should choose a model with the best quality which should not cause any harm to the environment. It should be eco-friendly. Some of the best brands which provide such products are eco-smart, eco temp, etc.
  • Looking Safety Details– We should look for a product which should provide proper safety by providing automatic sensors. These sensors detect harmful gasses such as carbon monoxide which automatically shuts down the system.

>> Read reviews and see photos on Amazon <<

Benefits Of Tankless Water Heater

Hot water usage has become much more convenient and energy efficient because of increasing need of people. Best tankless hot water heaters deliver more consistent temperatures by using less energy. Tankless heaters provide hot water all at once, and no preheating is required so they are very time-saving.

Benefits of Going Tankless-

  • EFFICIENCY – Tankless water heaters are efficient in both design and cost. Energy saving techniques are applied in these devices, so it saves our money.
  • CONVENIENT – The tankless water heaters can be installed in small spaces such as closets and crawl spaces. So space is a reliable feature. These devices send hot water to the needed sink, shower or dishwasher. The hot water is heated on demand, rather than stored, there is no limit to the amount of hot water that can be produced.
  • RELIABILITY – These water heaters feature very few problems. The problems of unexpected, short bursts of the cold water issues are solved through these machines. Conventional tanks can potentially flood and which could cost damages and repairs. The tankless heaters have a lifespan of about 20 years or more.
  • ECO-FRIENDLY – The water heaters use a little energy as possible, and they do not even produce any harmful emissions. Also, they produce as little greenhouse gas emissions into the air as possible, with electric models producing none at all. Some specialize brands for eco-friendly machines such as eco-smart, eco temp etc are providing such benefits.
  • CLEAN AND SAFE – Tankless water heaters are the best because they don’t build up rust or scale. So we can use this water safely while cooking or washing. They are also equipped with tons of safety features that vary from brand to brand.
  • INSTALLATION FLEXIBILITY – Indoor and outdoor, direct vent models are available in the market. Even costs of installation are low.
  • SAVE SPACE – Tankless hot water heaters take up significantly less space than traditional water heaters. They could also be mounted on walls either indoors or outdoors which is a very much beneficial feature.


With today’s rising costs of energy and environmental awareness in mind, different brands in the market has met and exceeded the expectations of home and business owners for new water heating solutions.  These products have gained great success by combining new technology and functionality in an innovative way to heat water. So finally they enhance our lifestyle, utilize technology and provide hot water at low costs. As these devices use energy to heat water so the basic fact about a good tankless water heater is no wastage of energy.


1.  “How It Works: Tankless Water Heaters”

2. Read more about tankless water heaters on Wikipedia.