Best Tankless Water Heaters 2018 – Reviews

A Complete Buying Guide for the Best Tankless Water Heaters

The tankless water heater is a strong investment every homeowner should make. Instead of getting a large-sized tank that will take space, require more maintenance, and could potentially damage your home, a tankless heater is safer and more efficient. Above all – it provides instant hot water. You can spend less time waiting and more time enjoying, while saving power overall.

You’ve undoubtedly had your spouse or children use all the hot water during a busy morning, leaving you with a cold shower. These heaters make that a problem of the past. Normal heating tanks store the water and then slowly heat it, requiring a great deal of power and time. However, the tankless variety constantly heats the water flowing to the necessary sources, minimizing energy output and providing instant results.

In addition, they’re easy to install and may not require a plumber to fix, should any complications arise. As these heaters areBest Tankless Water Heater an all-in-one unit, it’s just necessary to mount it on your wall, hook up some pipes, and voila!

However, throwing out your old tank and investing in new technology is not an easy decision. Which tankless brand is the best for you? Which features and specs should you look for? Are there any risks or concerns you should be aware of?

Never fear. To ensure you make the greatest buying decision, we’ve completed a line-up of the best, safest, and most affordable tankless water heaters available on the market, reviewing each in detail for your convenience. If you’re looking to make a great investment in 2018, then read on.

Best Tankless Water Heaters of 2018 – Reviews

Stiebel Eltron Stiebel $ 698.00 Stiebel-Buy-Now
Eccotemp Eccotemp $ 255.43 Eccotemp-Buy-Now
EcoSmart EcoSmart $ 449.98 EcoSmart-Buy-Now
Takagi Takagi $ 533.99 Takagi-Buy-now
Rinnai Rinnai $ 930.21 Rinnai-Buy-now


Stiebel Eltron Tempra 24 Plus Electric Tankless Water Heater

The Stiebel Eltron Tempra 24 plus Electric Tankless water heater is an excellent choice for your home. Stiebel-Eltron-Tempra-Best-Tankless-Water-HeaterIt has great features with an incredibly low price point, considering how much it accomplishes in such a small space. The low cost and numerous abilities turn it into an attractive offer you can easily buy on Amazon. The technology used in this heater is superior to many other brands of tankless electric water heaters, and we’ll explain why below.

Pros & Features:

  • Digital temperature control
  • No need for venting
  • Slim, easy to fit design
  • Saves energy, lowering your electric bill
  • It has a three-year warranty


  • What you may not like in this tankless water heater is the amount of water it heats at one time. Besides that, it is an excellent choice. It may not be a good choice for a shower but great for other needs around the home.
  • The price is also quite high as compared to many other models.

This German-made tankless water heater has a design that makes it easy to place anywhere. The weight of the device is also minimal, so if you follow the instructions properly, you can install it yourself without effort. You won’t need a plumber to do the job for you. The digital display is at the top with a manual adjuster below it.

The construction and technology of this heater ensures that you save at least 20% on your bills as compared to normal tank water heaters. What you will like most is the electric technology it uses to heat the water immediately, consuming only 240 watts. There is also the water flow settings, which you can now directly from the unit for more control and customization. You do not have to worry about temperature fluctuations, and no matter how much water is flowing, you will always get the same temperature from the outlet.

The Stiebel Eltron Tempra 24 does not require any venting. It is why you can fit the device anywhere. It is one of the most reliable tankless water heaters on the market, made even easier with its digital gauge. Directly from the unit, you can evaluate its status, progress, and settings with ease.

The price of this unit on Amazon is $698. Although the price may be a little on the high side, we recommend the Stiebel Eltron Tempra 24 Plus Electric Tankless as a useful, reliable and efficient water heater.

Brand Stiebel
Voltage 208/240 volt
Amperage 2×50 Min
Height 14 1/2
Dimensions 21.5 x 19.5 x 8.8 inches
Weight 15.4 pounds
Color N/A
Working pressure 150 PSI
Shipping Free
Warranty 3 Year
Customer Rating 4.8/5 By 143 Customers

Stiebel amazon BuyNow

Eccotemp FVI-12-NG High Capacity Gas Tankless Water Heater

If you are looking for a powerful tankless water heater with an effective heating system, then the Eccotemp FVI-12-NG High Capacity Gas Tankless Water Heater is a good choice. The water flow is constantTakagi T KJr2 IN NG and does not allow temperature drops. It is one of the cheapest models of tankless water heaters which are available on Amazon. We have reviewed a lot of water heaters but this one proved to be the best and the cheapest among the gas water heaters.

Pros & Features:

  • Digital temperature display
  • Easy to install with true 1/2″ NPT fittings
  • Sleek design makes it safe
  • 74500 BTUs
  • Efficient with a gas heating mechanism
  • 4.8 gallons per minute


  • Only a two-year warranty
  • Only good for smaller homes where the need for hot water is limited.

The Eccotemp FVI-12-NG High Capacity Gas Tankless Water Heater is a gas heater. This means straight away that you will save a lot on energy bills. Electric heaters, no matter how efficient, will still consume more energy than gas, making this an excellent choice if you are looking to downsize your budget. When the heater is idle, it only consumes 2 watts of power, and when operational and heating the water, it only consumes 10 watts of power.

The horizontal stainless steel kit ensures easy installation, and you do not have to worry about plumbing; just plug in the pipes and you are good to go. The gas heating mechanism used in the heater is also cheap, and can heat the water to 77 degrees Fahrenheit at its peak while keeping the flow at a maximum. It pumps 2.3 gallons per minute, which is more than enough to suit the whole house.

This heater has been tested for better performance. It has a state of the art electronic ignition system which ignites the flame. Once the flame is ignited, the gas keeps it alive. When you adjust the temperature, the flame rises or falls to increase or decrease the temperature. These results are then played on the digital monitor, making it easy to discern and control the temperature. Besides the digital temperature display, you will also like the gas and water controls.

The price of this tankless water heater is $255 on Amazon. The product also comes with a two-year warranty.

Brand Eccotemp
Voltage 110 volts
Hot water capacity 0.93 – 4.8 GPM
Height 14 1/2
Dimensions 4 x 15 x 24 inches
Weight 20 pounds
Color White
Gas rate 25,000 to 74,500 BTUs
Shipping Free
Warranty 2 Year Warranty Heater
Customer Rating 3.3/5 By 116 Customers

Eccotemp amazon BuyNow

EcoSmart ECO 27 Electric Tankless Water Heater

Among many, you will certainly want to buy this heater. The EcoSmart ECO 27 Electric Tankless Water Heater is an excellent choice for the household, as it’s reliable with a long lifespan, sure to service your needs for decades. If you want a water heater which is packed with various useful features, then this massive EcoSmart ECO 27 Electric Tankless Water Heaterheater (the biggest on the market) is a solid choice.

Pros & Features:

  • Endless supply of hot water
  • Excellent compact design
  • Digital temperature display and control
  • Lifetime warranty
  • Heats 3 gallons per minute
  • Self-modulation technology
  • More energy savings up to 50%


  • The price may be a little high
  • Lower flow rate than a few other models

If you are looking for an endless supply of hot water when you stand under the shower, buy this tankless water heater by EcoSmart. It is an electric water heater, made great because of its self-modulated heating technology. With this, the heater adjusts the temperature or regulates it based on how much water is pumped in and out. If you increase the water supply, the temperature will automatically adjust itself accordingly. This is a great advantage, especially if you are taking a shower.

The installation of this water heater is easy, requiring you to simply mount it on the wall, thus providing you extra space. The design is quite comfortable and sleek, and upon activation, will provide you with three gallons of hot water in one minute. What you will like the most is the one-degree increment feature; you can adjust the settings so that the temperature keeps on rising after every minute from 40 to 140 degrees Fahrenheit. It is a useful feature, especially if you live in a cold area.

As the name tells, it is Eco Smart, meaning it saves energy – mainly because it operates at 240 volts. Another feature which you will like in this unit: it’s made of stainless steel. The internal components are also made of pure copper, increasing its durability and efficiency. Make sure that you purchase this water heater at Amazon, where you will get a bigger discount.

Overall, it is an efficient water heater and saves money too. The fact that it has a lifetime warranty makes it the most obvious choice. The price of this tankless gas water heater is $438, which may be a bit high, but it is packed with the features you need the most at home.

Brand EcoSmart
Voltage 240 volt
Max Amperage 33
Water Connections 1/2″ CF
Dimensions 11.5″ x 8″ x 3.75″
Weight 16.8 pounds
Color N/A
Required Breaker 1 x 40 AMP
Shipping Free
Warranty Life-time
Customer Rating 4.3/5 By 615 Customers

EcoSmart BuyNow

Takagi Indoor Tankless Water Heater

Among many other brands of water heaters is the Takagi Indoor Tankless Water Heater. It is a large-sized heater which utilizes natural gas to warm the water, both saving money and helping the environment. It is available in a white color which makes it attractive and better for wall-mounting.Takagi T KJr2 IN NG

Pros & features:

  • Excellent flow rate i.e. 6.6 gallons per minute
  • 140,000 BTUs
  • Constant temperature monitoring
  • Saves energy
  • Stainless steel body makes it durable
  • Has EnergyStar certification
  • 10-year warranty.


  • The installation requires a certified technician
  • You get the warranty only when it is fitted by a certified technician.
  • No digital display

This Japanese-made Takagi Indoor Tankless Water Heater is a good choice for home use. It heats up to 6.6 gallons of water per minute at your desired temperature. This is what makes it a brilliant choice – you do not have to worry about the number of people at home. With the fast flow rate, it will pump hot water to the entire house. With the 140,000 BTUs, it is an extremely powerful device.

The Takagi Indoor Tankless Water Heater is one of the sturdiest models on the market. It has a category-three stainless steel body. The 4-inch steel ensures that you get a reliable product.
What you will like about this model is the technology used to heat the water and maintain it; the in and out thermistors control water temperature. It is a good choice for residential use.

The device is also rated as frustration-free. It means that once you install it, you can leave it. It will work automatically to heat the water. Since it works on gas, you will have to turn on the unit and ignite the flame. Once it is turned on, you can adjust the temperature easily.

One of the features which you will like about his mode is that it includes a frost guard for cold temperatures. The automatic mechanism of the heater ensures that it will turn off when the unit overheats, so this prevents damage and also saves money.

The price of the Takagi Indoor Tankless Water Heater at Amazon is $539.99, which is quite high as compared to other models. But the technology in it ensures that you will get a constant supply of hot water for the house.

Brand Takagi
Voltage 208/240 volt
Water Capacity 6.6 GPM
Origin Japan
Dimensions 6.7 x 13.8 x 20.3 inches
Weight 37 pounds
Color N/A
Gas Rate 140,000 BTU
Shipping Free
Warranty 10 Year
Customer Rating 4.6/5 By 170 Customers

Takagi amazon Buy Now

Rinnai Natural Gas Tankless Water Heater

Are you tired of getting up in the morning and having no hot water for a shower? Well, it is time you got the best tankless water heater for your home. There are many models available on the market, but one of the best that we found is the Rinnai Natural Gas Tankless Water Heater.
It is an expensive model, but it has some of the best features which are not present in many others. If you want a highly recommended heater regardless of price, then we suggest this one.Rinnai RL75iN Natural Gas Tankless Water Heater

Pros & features:

  • Import quality
  • Error code indicator
  • Digital controller
  • Thermal efficiency up to 82%
  • Excellent design and easy to use
  • 12-year warranty
  • Certified energy star product


  • High price

We recommend the Rinnai Natural Gas Tankless Water Heater because you can now power various appliances with this. You can have the hot water supplied to the bathroom, kitchen, and many other appliances at once. One of the best things about this heater is its thermal efficiency. It provides up to 83% thermal energy savings, meaning you will save a lot on gas energy bills, seeing as it uses state of the art gas heating technology.

There are not many models which provide error code indication. Often you may find it difficult to know what is wrong with the unit. Thanks to the error indication mechanism, now you can know what exactly the problem is. The digital controller allows easy management of the water temperature. It is the latest MC-91-1US Digital Controller.

The design of this model is also excellent. The inlet is at the top, and the outlet at the bottom. You can easily install the unit yourself. With this water tankless heater, you can set the residential temperature from 98 to 140 degrees Fahrenheit, and the commercial temperature settings which range from 98 to 160 degrees Fahrenheit.

With this unit, you can get an average of 7.5 gallons per minute. It is the best choice if you need large quantities of hot water for the entire household. You may have to pay a large sum of money, but you will get peace of mind. This Rinnai Natural Gas Tankless Water Heater has a 12-year warranty, and the price is $939 at Amazon. It is one of the most highly recommended tankless water heaters on the market, but also one of the most expensive.

Brand Rinnai
Voltage 208/240 volt
Size  Large
Water Capacity 7.5gpm
Dimensions 14 x 9.3 x 23 inches
Weight 50 pounds
Color Silver
Gas Rate 180,000 Btu
Shipping Free
Warranty 12 Year
Customer Rating 4.2/5 By 87 Customers

Rinnai Buy Now

Best Tankless Water Heater Reviews


How Should You Choose a Tankless Water Heater?

Each water heater you find on the market has a few features which are better than other models, and visa versa. However, there are a couple of deciding factors you should know about, which will help you make a better buying decision.

The size of the water heater

There are many models available in different sizes. Always buy a tankless water heater based on their size, as its placement within the home as well as its horsepower will come into play. For example, if you want a unit in the kitchen, you may want to consider a smaller one with less capacity. But if you want a unit in a bathroom for a shower, then you may want a model in a larger size. The size of a water heater also determines how easy it is to install. The large ones need a plumber to fix and install; a small unit, however, is easy to do yourself.

The water flow rate

The flow of water is an important consideration. There are many models which have a lower flow rate compared to other models, such as gas vs. electric. You will want a water heater with an increased flow rate if you choose it for bathroom use, while a kitchen one may benefit from a low flow rate.

Heating time

Another important consideration is how long it takes to heat the water. Usually, tankless water best water heaterheaters do not take much time at all, but there is a slight difference based on the type. Gas tankless water heaters take less time to heat the water as compared to electric water heaters.

The warranty

Warranty plays an important part in buying the unit. Make sure that you get as long a warranty as possible. These heaters mostly have a three-year warranty, but a lifetime warranty on parts is a possibility.

The controls

The tankless heater should be easy to use. Make sure that you purchase a model which has digital controls so you can navigate the settings smoothly and accurately. These units may be a bit expensive but will provide you peace of mind. You only have to press a button to start or stop the unit and adjust the temperature.

The price

The price is also an important factor to consider while buying a water heater. If you are looking for a cheaper model, then purchase the gas-powered tankless water heater. These heaters are at least 15 to 20 percent cheaper than the electric heaters. On average, the price of these water heaters range from $200 to $1000. The high cost means that the heater will have more features and better controls.

The type of heater

The most important consideration is the type of heater. There are two types based on the mechanism used to heat the water: gas and electric. Gas heaters are a much cheaper choice but electric heaters provide better controls.

The brand
Make sure that you only purchase water heaters from reliable brands. Some businesses may claim quality but not deliver it. Instead, a trusted brand will have reviews, ratings, and testimonials to give you peace of mind.

The number of appliances you can attach with the unit

Last but not least is the number of appliances you can attach to the water heater. There are a few heaters which only power one room – i.e. a bathroom or a kitchen. There are a few models which can provide hot water to the entire building. Always choose the type of tankless water heater based on your needs.

Best Tankless Water Heaters

How Does a Tankless Water Heater Work?

It is important that you know the inner workings of your investment before you click ‘buy.’ Only then can you understand the benefits of what you’re adding to your home. Let us break it down for you.

• When you turn on the unit, the water enters the heater through the pipe. The pipe may be at the top or at the bottom, depending on the model. When the water enters the pipe, the mechanism in the heater signals to activate the flame (in the case of gas heaters) or start ignition.

• To keep the flame ignited, there is a fan inside the unit which pumps oxygen to the burner. Until the flame is at the desired level, the igniter will keep igniting the flame. It will only stop when the flame is adequate.

• The water heating mechanism involves copper wires. The copper coils are present in the copper heat exchanger. The water passes through the inlet pipe and then over the wires where it is heated. Then it passes through and to the outlet pipe.

• There are many models in which the water is also preheated before entering the heating chamber. It means these models have two chambers or heat exchanges. These models provide hotter water.

• The blower and the gas valve work together to adjust the fuel and oxygen. If you ask for more heat, the flame will be increased by boosting the fuel and oxygen. These controllers work together and activate in a matter of seconds. You will get instant heat and hot water of your desired temperature.

These tankless water heaters have a digital controller through which you can control the temperature. This is how the entire unit works. Make sure that the water heater you get is reliable.

Final Thoughts:

These top five reviews have been thorough and comprehensive, but admittedly, it’s a lot to swallow at once, especially if this is your first buy. Allow us to condense our verdict on tankless water heaters for you here now.

Both the types of heaters – i.e. the tankless gas water heater and the tankless electric water heater – are an excellent choice. While you get what you pay for, in this scenario, it’s wiser to side with the latest technology, as it allows your home – and heater – to work smarter, not harder. These heaters will provide a more efficient and constant supply of hot water, and require no ‘warm up’ time. As they’re smaller machines and can line up with your current energy usage – whether you prefer electricity or gas – they can conveniently assimilate to your home, without complicated installation or any revamping needed from you.

In addition, these advanced technology heaters are affordable compared to many other brands, especially if you choose the gas option, which is much more cost effective in the modern day. Take some time, think it over, re-read our reviews, and prepare to make the best investment of 2018!

1 thought on “Best Tankless Water Heaters 2018 – Reviews

  1. Great write up guys! Stiebel Eltron tops the list in my book, then Rinnai would be second, the both of these are great for large families or heavy hot water usage households. ECO Smart and Ecotemp are a good option for people on a budget, smaller households or light hot water usage.

    Thanks Guys!

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