Best Tankless Water Heater

We spent one week researching about the best tankless water heater. Subsequently, we declare that EcoSmart ECO 27 Electric Tankless Water Heater is the best we can get in the current inventory of various premium quality tankless heaters. We researched and considered various types of tankless heaters for fast hot water.

What is a Tankless or On-Demand Water Heater

Tankless water heaters use electric or gas powered burners to heat water as the water runs in the pipe of heat exchanger. You can also call them on-demand water heater. These heaters directly deliver water to the shower or faucet or tub.

There is no need for a tank to store water. These heaters use electricity or gas as energy and they are energy efficient too. Tankless heaters cost 22% less power than typical tanked heaters.

If you use less than 40 gallons water, then tankless heater is best for you. It can save $50-$100 per year based on electric or gas powered on demand water heater. These heaters have longer life than regular tanked heaters.

Takes low to no space and installing it anywhere is possible. In addition, you will get hot water anytime you want. Most importantly, You don’t have to wait for hot water, just start the heater and you will get hot water.

Top 10 Tankless Water Heaters Comparison Chart

 ImageNamePowerFlow RateConnectionsColorCertification
1EcoSmart ECO 27 Electric Tankless Water HeaterEcoSmart ECO 27Electric6 GPM3/4'' NPTWhiteUL & CSA
2Takagi T-KJr2-IN-NG Indoor Tankless Natural Gas Water HeaterTakagi T-KJr2-IN-NGNatural Gas6.6 GPM3/4'' NPTWhiteENERGY STAR
3PrecisionTemp RV-550 Tankless Water HeaterPrecisionTemp RV-550Propane1 GPM3/4'' NPTWhiteNone
4Stiebel Eltron 224199 240V 24 kW Tempra 24 Plus Tankless Whole House Electric Water HeaterStiebel Eltron 224199Electric5 GPM3/4" NPTAshCertified
5Rheem RTG-64DVLN Prestige Indoor Tankless Natural Gas Water HeaterRheem RTG-64DVLNNatural Gas6.4 GPM3/4" NPTAshENERGY STAR
6Rinnai V65IN 6.6 GPM Indoor Tankless Low NOx Propane Water HeaterRinnai V65EPPropane6.6 GPM3/4" NPTWhiteNone
7Bosch Tronic 2.5-Gallon Electric Mini-Tank Water HeaterBosch Tronic 3000 TElectric2.5 GPM1/2" NPTWhiteNone
8Sio Green IR260 POU Electric Tankless Water HeaterSio Green IR260Electric1.5 GPM1/2" NPTWhiteNone
9Eccotemp FVI-12 Liquid Propane, 3.5 GPM, Tankless High Capacity Water HeaterEccotemp FVI12-LPPropane3.5 GPM1/2" NPTWhiteGAMA/UL
10gasFlex Excel Pro Tankless NATURAL GAS Whole House Water HeatergasFlex Excel ProNatural Gas6.6 GPM3/4" NPTWhiteSGS

Best Tankless Water Heater Reviews

Finding the best tankless heater wasn’t easy for us. We from the Duly Reviewed team were confused making our decision to get the best rated tankless heater. Then we came to understand that we can certainly choose one as the best tankless water heater.

However, we couldn’t ignore other top rated tankless heaters also. There are mainly two types of tankless on demand water heaters, electric and gas powered.

Certainly, electric heaters are better but there are some good quality gas powered tankless heaters. Those are better than many top rated tankless electric water heaters.

So, we listed the best quality tankless electric water heater along with the best quality tankless gas water heater. We also included the best RV tankless water heater into our list because ignoring this type can be a huge mistake.

The best on demand water heater for RV or portable water heater is popular on the market. Moreover, their popularity and use are increasing day by day. So, we have listed these 3 types of heaters reviews for instant hot water.

Similarly, we also listed some other best rated on demand water heaters reviews. This will give you enough option to choose from. The best one will satisfy all your requirements and conditions.

Best Rated Heaters

There are many types, sizes and features available when choosing the best tankless heater. You can’t just choose the top rated on demand water heater as the best heater.

We have to consider all the features including power consumption, effectiveness, speed, guarantee, cost etc in mind. It will help you find the most suitable tankless on demand hot water heaters for the money.

We choose 3 best rated tankless heaters, 1 for each type of on demand water heater. Tankless heaters are expensive so we recommend you carefully understand your need and requirements before making a decision.

Also, installing tankless heater requires expert hand so do it yourself if you are not confident about your installing ability. Therefore, you should hire an expert or professional for installing your tankless heater on your water line.

Best Overall Tankless Electric Water Heater

EcoSmart ECO 27 Electric Tankless Water Heater

EcoSmart ECO 27 Electric Tankless Water Heater

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We choose the EcoSmart ECO 27 Electric Tankless Water Heater as our best electric tankless on demand water heater. Most importantly, for its extraordinary features and effectiveness.

This tankless heater is most suited for northern part of US where the average temperature is around 37°F. It can produce about 3 gallons of hot water per minute. Enough to run 2 showers at a time.

If you wish to use it in the southern part of US where the average temperature is high. Then it can produce 6 gallons of hot water per minute, enough for running 4 showers and a sink at a time.

Subsequently, it is a great fit large home and small hotels. For either norther part or southern part, you will never run out of hot water using this EcoSmart ECO 27 Heater.

Its temperature control is awesome and you can set and increment the temperature by 1 degree at a time. This digital temperature control system can operate with range of 80°F to 140°F enough for healthy bath.

EcoSmart ECO 27 will reduce energy cost by 50% because of its unique technology. Tanked water heater requires a lot of space. However, using this tankless electric heater will save a lot of space.

Because, it is wall mounted and will take tiny space on your wall. This energy saving best rated tankless electric water heater can fit with the standard 3/4 inch NPT pipe.

In addition, you will require 3 sets of 8 AWG wires to set it. EcoSmart ECO 27 CSA certified tankless water heater has 99.8% electric efficiency.

EcoSmart ECO 27 Electric Water Heater will require 240V electric power with 112.5 A current and it will cost 27 KW per hour. This extremely powerful and effective water heater comes with lifetime warranty.

Best Overall Tankless Gas Water Heater

Takagi T-KJr2-IN-NG Indoor Tankless Natural Gas Water Heater

Takagi T-KJr2-IN-NG Indoor Tankless Natural Gas Water Heater

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If you are looking for the best tankless gas water heater instead of the electric water heater? Then our pick is the Takagi T-KJr2-IN-NG Indoor Tankless Natural Gas Water Heater. This is the best rated tankless gas on demand water heater.

It comes with 140,000 BTU of heat and work extremely well. Takagi T-KJr2-IN-NG is a natural gas powered tankless heater that is best fit for indoor uses.

It can produce 6.6 gallon of hot water per minute, enough for running 4 showers and 2 sinks. This amount of water is enough to run acrylic bathtub and other types bathtubs.

Takagi T-KJr2-IN-NG will require 4 inch stainless steel category III venting. This water heater is equipped with inlet/outlet thermistors. That is to say, you can regularly monitor the water temperature and adjust if required.

Takagi T-KJr2-IN-NG is ECO-friendly and the best gas tankless heater for small home and apartment. It comes with 10 years warranty for heat exchanger and 5 years warranty for parts.

The warranty is only valid if the whole unit is installed by properly licensed or vendor approved technician. Also, you should buy this top rated heater from certified and authorized vendors only.

Best Overall RV Tankless Water Heater

PrecisionTemp RV-550 Tankless Water Heater

PrecisionTemp RV-550 Tankless Water Heater

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Are you a RV fan and spend a lot of time with your RV? Then you will require a specifically designed water heater for your RV. Tanked water heaters are hassle for small spaced RV.

You will require a water heater that takes low to no space at all. It is better to find the best RV tankless water heater and the PrecisionTemp RV-550 Tankless Water Heater is the best rated RV water heater you can get.

PrecisionTemp RV-550 is specifically designed and manufactured for RVs, small apartments and trailers. This wall vented tanless heater is easy to install and remove.

In other words, it is a perfect fit for your RV lifestyle. It will take half or less space than 10 gallon tank and that can save a lot of space in your RV.

PrecisionTemp RV-550 is highly energy efficient and will cost lowest amount of propane. Also it will require no pilot light.

PrecisionTemp RV-550 uses 1.5 Amp power normal times but uses 3 Amp if you activate the cold weather protection. It has built-in freeze protection option for all 4 seasons. However, you have to keep the gas supply and 12 Volt power supply on.

It can produce over 1 gallon of hot water per minute. This highly recommended RV water heater is fully assembled, tested and designed in US.

PrecisionTemp RV-550 Heater is well suited for any sized trailers and RVs. This best RV heater comes with no defined warranty so you have to ask the vendor about warranty before buying this.

Top Rated Heaters

Though, above 3 listed heaters are best among their tankless heater types. However, they are not the only high quality tankless heaters on the market. Likewise, there are many other top rated tankless heaters.

The below listed water heaters are tankless too. By no means, they are inferior to the above best rated water heaters. In addition, they have high quality features. Some are economical and most suitable too.

You should check the complete list and read the whole tankless water heaters reviews. Moreover, you must understand your requirements. After that, you will get what you want.

Stiebel Eltron 224199 240V 24 kW Tempra 24 Plus Tankless Whole House Electric Water Heater

Stiebel Eltron 224199 240V 24 kW Tempra 24 Plus Tankless Whole House Electric Water Heater

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Stiebel Eltron 224199 240V 24 kW Tempra 24 Plus Whole House Tankless Electric Water Heater is one of the top rated tankless electric heaters.

Stiebel Eltron invented tankless water heating technology almost a century ago powered by electricity. This electric heater is silent, small and compact.

In other words, it will use no space at all comparing with tanked heaters. This water heater requires no venting and that is a huge plus.

Its Self-Modulating Power Technology ensures 99% energy efficiency. Moreover, it will only be active when you will need hot water. In addition, it has no power losses while being on standby.

Stiebel Eltron Tempra has Advanced Flow Control feature. For instance, you get constant temperature for hot water for your rain shower head and sinks along with other faucets.

Stiebel Eltron 224199 can produce 2.6 gallon hot water at 42°F and 5 gallon hot water at 72°F. It is less expensive than other best rated electric tankless water heaters.

Installing this electric water heater is easy because it requires no venting setting. This top rated electric tankless heater comes with 7 years leakage warranty in addition with 3 years warranty for parts.

Eccotemp L10 2.6 GPM Tankless Portable Water Heater

Eccotemp L10 2.6 GPM Tankless Portable Water Heater

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This is a great tankless water heater for RV and outdoor use. Eccotemp L10 Portable Outdoor Tankless Water Heater is lightweight and easy to carry.

For washing your pet or outdoor showers, there is no better tankless water heater than this. Installing it on your RV is also easy. Great service life and constant hot water for RV.

As one of the best propane tankless heater it runs on 20 lb propane tank. It runs with 2 “D” cell batteries and comes with electric ignition.

Eccotemp L10 has a safety feature for automatic shut down. If it is tilted 45 degrees either side or runs longer than 20 minutes, it will automatically stop.

Eccotemp L10 can produce hot water with temperature range of 50-140 degree F and its water output is rated 2.6 GPM. You can connect this water heater with your rv shower head or garden hose easily.

This tankless portable RV water heater comes with necessary installation kits. This best rv tankless water heater comes with 1 year product warranty.

Rheem RTG-64DVLN Prestige Indoor Tankless Natural Gas Water Heater

Rheem RTG-64DVLN Prestige Indoor Tankless Natural Gas Water Heater

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If you are looking for the best tankless natural gas water heater then you can choose Rheem RTG-64DVLN Prestige Indoor Natural Gas Water Heater without further investigation.

It is one of the best indoor gas water heaters that runs on natural gas. This top rated natural gas tankless heater can produce 6.4 gallon hot water per minute.

This ultra low nox water heater uses direct vent setting for indoor use. The package comes with 10 feet long thermostat wire and remote control system.

Rheem RTG-64DVLN can produce 35 degree rise hot water than normal temperature. With EZ-Link cable, you can connect two of this best quality heaters and use them as one.

This water heater comes with 1-10 years limited warranty. The warranty vary based on different models, conditions and features.

Rinnai V65EP 6.6 GPM Indoor Tankless Low NOx Propane Water Heater

Rinnai V65IN 6.6 GPM Indoor Tankless Low NOx Propane Water Heater

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There are various high quality and top rated tankless heaters those produce great result. And Rinnai V65EP 6.6 GPM Tankless Indoor Low NOx Propane Water Heater is one of them.

This ultra low nox tankless water heater runs on Propane . It is specifically built for indoor use. Rinnai V65EP produces 150,000 BTU max with 0.82 max power factor.

It fully meets the requirements for NOx Emissions Standards of Florida and California. Rinnai V65EP has compact setting and lightweight too. These features make its installation easy and smooth.

This best tankless Propane water heater has different periods of warranty for different parts. Rinnai V65EP comes with 1 year labor warranty, 5 years parts warranty and 10 years Heat Exchanger warranty.

Bosch Tronic 3000 T 2.5-Gallon Electric Mini-Tank Water Heater

Bosch Tronic 2.5-Gallon Electric Mini-Tank Water Heater

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Though, Bosch Tronic 2.5-Gallon Electric Mini-Tank Water Heater comes with mini tank. However it is still counted as one of the best tankless electric hot water heater.

It can produce 2.5 gallons of hot water per minute. This small electric water heater is good fit for sinks, small showers and small tubs.

On the other hand, not good enough for rain shower heads or regular sized bathtubs. This 120 V tankless water heater uses 12 A current.

Bosch Tronic Heater is easy to maintain meanwhile cleaning the small tank also easy. You can mount it on wall, shelf or floor, wherever you like.

Bosch Tronic Mini-Tank Water Heater has higher recovery rate. So, you don’t need to wait long for hot water. It is good enough for 2 sinks at a time.

This top rated electric mini tank water heater is good for indoor use. Bosch Tronic comes with 2 years parts warranty and 6 years heater and tank warranty.

Sio Green IR260 POU Electric Tankless Water Heater

Sio Green IR260 POU Electric Tankless Water Heater

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Sio Green IR260 POU is another top rated tankless electricity powered water heater. It runs with 220-240 V and 10-30 A electricity or 6 KW power.

Sio Green IR260 will produce hot water in no time with its high technology and fast water boiling system. It uses patented and unique technology that requires no metal coil to heat the water.

This Sio Green IR260 will produce no calcium buildup, limescale deposit or corrosion. So, you need no replacement parts or filters and your maintenance cost will low down to $0.

Moreover, this top quality tankless heater comes with 2 years money back guarantee or free replacement without asking any question. You can set this best rated water heater almost anywhere you want.

This can be used as a portable water heater or tankless heater for RV. You can also use it as a worthy alternative for electric hot water shower or add it with your tub.

Eccotemp FVI12-LP Liquid Propane, 3.5 GPM, Tankless High Capacity Water Heater

Eccotemp FVI-12 Liquid Propane, 3.5 GPM, Tankless High Capacity Water Heater

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As one of the top rated tankless gas hot water heater Eccotemp FVI12-LP Liquid Propane, 3.5 GPM, Tankless High Capacity Water Heater has great capacity and features.

This water heater will only be active when used. Eccotemp FVI-12 makes it energy saver and cost effective. It runs on liquid propane.

It can produce hot water with 3.5 GPM and its enough for whole house tankless water heater. Eccotemp FVI-12 produces low noise and it has really compact size and design.

Its digital temperature display is simple and easy to understand. Great for small sized home or apartment.

With its electronic ignition system 120 V power supply option, it is safer than many other tankless gas water heaters with similar features.

You can use it to fill your inflatable hot tub with hot water in a few minutes. The Eccotemp FVI-12 Water Heater comes with additional parts and 2 years limited warranty.

gasFlex Excel Pro Tankless NATURAL GAS Whole House Water Heater

gasFlex Excel Pro Tankless NATURAL GAS Whole House Water Heater

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gasFlex Excel Pro Tankless NATURAL GAS Whole House Water Heater comes with modern technology and features. Comparing with other top level tankless natural gas water heater models, it works better than them.

This high quality tankless gas water heater runs by natural gas. It can produce hot water of 6.6 GPM speed, enough for whole house use.

You can run 4 sinks, 2 showers and 2 bathtubs at a time with 6.6 GPM. It has SGS certification. This copper made tankless gas water heater needs 110 V electric connection.

In addition, it is safer than many others. gasFlex Excel Pro can heat the water upto 35 degree F instantly so you will never run out of hot water.

The whole package contains necessary parts and it has a 2-6 years limited warranty for parts and heaters.

As the best whole house tankless natural gas water heater you can compare gasFlex Excel Pro any other heaters and still choose it.

Thermoflow Elex 3.5 Tankless Point-of-Use Electric Water Heater

Thermoflow Elex 3.5 Tankless Point-of-Use Electric Water Heater

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We will end our list of best tankless water heaters with the Thermoflow Elex 3.5 Tankless Point-of-Use Electric Water Heater. Great for instant hot water for low quantity.

This is a small tankless electric portable water heater best suitable for single sink or faucet. It produces hot water with a speed of 0.5 GPM enough for a sink.

Thermoflow Elex will save around 60% cost for hot water. Moreover, it will produce unlimited hot water with 0.5 GPM speed as long as you need from the first minute.

It uses 220-240 V, 17 A current and 3.5 KW power and 90 PSI nominal pressure. If you have all these then you can buy this high quality tankless small electric water heater.

Thermoflow Elex comes with required spare parts and 2 years seller warranty. The warranty will start from the day you bought this tankless compact electric water heater.

End Words

We have listed here all the best tankless heaters based on their product specifications and customer reviews. Before you choose any best tankless electric water heater, you should check your electric connection options and other requirements.

If you choose to buy the best tankless gas water heater, you should make sure you have enough space and security and electric option for a tankless gas heater. Read complete guide for tankless hot water heater.

For RV or portable or compact tankless heater, make sure you choose the best tankless rv water heater otherwise you may face many difficulties in the near future.

Whichever you choose, you must consult with a professional. Therefore, the professional can instruct you which water heater is best for you both economically and practically based on your requirements and needs.