Best Electric Tankless Water Heaters of 2020 – Ultimate Review

| Last Updated: May 2, 2021

Modern times require modern solutions, and that is exactly why you need an electric tankless water heater. These tanks are making their mark in the industry and for all the right reasons.

They instantly heat water and come with a sleek design for easier installation. But more on that later.

Need to Hire a Plumber for a Water Heater?
Get help from a qualified plumber in your area now!

Below is everything that you need to get your hands onto the best model. Invest wisely and make your life comfortable and convenient.

Comparison Chart of the Best Electric Tankless Water Heaters

  • Activation flow is 0.3 GPM
  • Allows control in 1 degree of increment control
  • Copper and steel construction for increased durability
View Latest Price →
  • Only requires 240 volts to run
  • Allows for full digital control of the water
  • High reliability which makes it a great investment
View Latest Price →
  • Best for the money
  • Requires 12 A to work only
  • Compact design allows for easy fitting
View Latest Price →
  • Comes with a 99% efficiency
  • Best Eemax electric Tankless water heater
  • Allows for easily adjustable temperature display ranging from 80 to 140 degrees
View Latest Price →
  • Comes with a filter on the inlet
  • Best Marey Electric Tankless water heater
  • Can adapt to your home’s electrical capacity
View Latest Price →
  • Comes with an energy efficiency of 97%
  • Best Bosch electric Tankless water heater
  • Made with elements encased in a polymer substance
View Latest Price →

What Size of Electric Tankless Water Heater Do I Need?

Buying the right size of a tankless heater is paramount to achieving all the other benefits of the product. Here is how you can ensure that you are getting the right size of an electrical heater for your home.

Firstly, you need to identify the peak demand flow rate of your house. This indicates the time period or the time range where your family uses most of the hot water. Most families in the world use hot water in the morning for showers, cleaning, and cooking. After this, you will have to look for the GPM of each water appliance that you use. Add them all up to calculate the right amount.

The next step is to calculate the estimated temperature rise of the water. You can do this by simply subtracting the groundwater temperature from the output temperature. This is simple math and can be easily done on a calculator. If your groundwater is 60 degrees, and the output temperature needs to be 100, then your temperature rise would be 40 degrees.

Lastly, you need to look out for the tankless heater size that fits your criteria, and you are good to go. These measurements are frequently advertised so you won’t have a hard time selecting the right sized water heater.

How Do I Choose an Electric Tankless Water Heater?

You already have a brief idea of what an electric tankless heater is and why it’s so important to keep one in the house. Now let us see some of the best features that you need to look out for when buying a tankless heater for your home or your office.

Need to Hire a Plumber for a Water Heater?
Get help from a qualified plumber in your area now!

Easy and Flexible Installation

This is important because it is the first step to ensure convenience and comfort for you. You need to find a model that comes with an easy guide and flexible spot options for easy plugging in of the system.

Digital Control

The purpose of the heater being tankless is to bring more ease to you, and hence that purpose is further aided by a digital control system. This will not only allow you to set the exact temperature of the water you require, but it will also ensure that unnecessary electricity is not consumed by the heater when you are on vacation or outside of your home for too long.

Energy Efficiency

In this modern world, nearly everyone is looking for safer and better options to save energy and cost. Thus investing in the right product will ensure that maximum energy efficiency is achieved. Moreover, it will also allow you to save on your costs as the bill will be significantly reduced by the presence of an energy-efficient product.

Disease Protection

Safety should also be a top priority when it comes to tankless heaters. Investing in a good quality product from our list will help you get rid of any harmful material or bacteria that might reside inside a tank heater. 

Quick Take: Best Electric Tankless Water Heaters

Review of the Best Electric Tankless Water Heaters

If you have read the above sections properly, chances are you are already convinced that you need a good electric tankless heater, but what exactly is a good model? Here is a list of the top-of-the-line products on the market. Read all about them and choose the one that fits your needs.

EcoSmart ECO 27 Electric Tankless Water Heater, 27 KW at 240 Volts, 112.5 Amps with Patented Self Modulating Technology,White


  • Comes with a digital water control
  • Allows for easy replacement when needed
  • Ensures an endless supply of hot water at all times
  • Smooth construction adds to durability and efficiency
  • Compact shape helps save storage space in the house


  • Can be overloaded in very large homes
  • Relatively expensive than some other models
  • Does not come with a remote temperature control

What Recent Buyers Report

It’s hard to fulfill the expectations of recent buyers, but this tankless heater has done it with ease. The model comes with a good activation flow and an easy installation process. Moreover, it is also praised for bringing a nonstop flow of hot water at all times. It also enables you to control the temperature of the water via its digital water controller.

Why it Stands Out to Us

The best thing about this model is its self-modulating advanced technology. This is a relatively new technology that is quite rare in most tankless heaters. It allows the product to adjust the amount of energy required and thus carefully heats the water to the required temperature. In doing so, the model is able to reduce heat and energy consumption by 50%.

Who Will Use This Most

The product comes with a sleek and compact design, thus making it perfect for people with relatively smaller spaces. Unlike other traditional heaters, it does not require a lot of space for mounting. It helps free up the additional floor space by providing an easy fitting and installation of its lightweight design.

Bottom Line

If sized correctly, this tankless heater will ensure the best possible results for you. It not only has a compact and lightweight design, but it also comes with easy access. Moreover, the installation is quite convenient and doesn’t require professional assistance. In case of any breakage or problem, which is quite rare, you will find replaceable items easily.

Stiebel Eltron 224199 240V, 1 Phase, 50/60 Hz, 24 kW Tempra 24 Plus Whole House Tankless Electric Water Heater, Advanced Flow Control


  • Saves more than 15% on your bills
  • Has a sleek design for easy storage
  • Does not require any sort of venting
  • Ensures a completely silent operation
  • The shower always stays hot for more comfort


  • Requires a professional to install it
  • Installation costs are often very high
  • Relatively heavier than some other models

What Recent Buyers Report

The product has garnered huge praise from recent buyers and fans alike, for all the right reasons. The Steibel tankless heater comes with a fully digital controller that only requires 240V to run. Not just that, the product doesn’t require any venting, thus making it easy to install, maintain, and manage.

Why it Stands Out to Us

The best thing about this product is its sleek design and the presence of a fully digital controller. This means that your model will not allow you to choose the exact temperature that you want. The controller is extremely easy to operate, thus making it reliable to be used by you and your whole family. Moreover, the product saves on your bill, which is also another reason it stands out to us.

Who Will Use This Most

The product is made for people who like to take their baths in complete silence and without worrying about outside components. It comes with an advanced technology that enables a completely silent operation for a comfortable bath. Moreover, its sleek design saves on storage space, thus making it an easy fit for smaller homes.

Bottom Line

Steibel has worked tirelessly for more than 90 years to bring its customers a set of reliable products that ensure more comfort and convenience. This tankless heater sticks to the same standards and provides greater efficiency and reliability to all its customers. The shower stays hot at all times, meaning that you will get consistent results with this heater at all times.

Ecosmart ECO MINI 2.5 2.5-Gallon 120V Electric Mini Tank Water Heater


  • Higher warranty thus lasts longer
  • Good and reliable manufacturing
  • Sleek design is appealing to the eyes
  • Does not require installation of any recirculating lines
  • High energy efficiency helps save 99.8% of extra energy used


  • Not very easy to install
  • Can overload an existing circuit
  • Model does not come with any suitable guidance or instructions

What Recent Buyers Report

Recent buyers who care about their energy consumption are very pleased with the performance of this superior model. The Eco-Smart enables all its users to use less energy and thus save on cost, but that in no way means that it doesn’t ensure hot water consistently. The good and reliable manufacturing of the product produces constant hot water at all times.

Why it Stands Out to Us

The product stands out to us because of its higher warranty, but that’s not the only reason why it’s considered one of the best products on the market. It saves more than 99% of your energy, thus ensuring that both your money and your energy consumption is reduced. Therefore, with this model, you can not only save on the cost but also play your part towards less global warming.

Who Will Use This Most

While designing their homes, people often care a great deal about appearances. They want each inch of their houses to reflect grandeur and beauty, and this is exactly where this model comes in handy. It has a smooth and stylish design that appeals to the eyes and thus matches the interior of your house. Moreover, its lower cost makes it affordable for many people.

Bottom Line

The model is relatively hard to install, but once you get that out of the way, it’s all amazing with this amazing tankless heater. The Eco-Smart comes with all the perfect features of a heater in a small compact design that saves on storage space. Moreover, it is made with strong manufacturing materials that add to its durability and reliability.

Best Eemax Electric Tankless Water Heater:
Eemax HA011240

Eemax HA011240, Grey, 6 Gauge


  • No need of any additional storage capacity
  • The unit can be mounted directly on the wall
  • Does not allow any legionella bacteria growth
  • Does not require any soldering during the installation process
  • All components of the model are replaceable in case of breakage


  • Slightly heavier than some models
  • Not very efficient in terms of money
  • Range of operating temperature is relatively lower than some other models

What Recent Buyers Report

When recent buyers are getting hot, comfortable water instantly, why would they complain? The Eemax electric tankless water heater is received with a lot of love because they ensure safety with convenience. They contain all the components of high manufacturing that can be easily replaced if a situation arises. Moreover, they come with easy installation, thus adding to its appeal.

Why it Stands Out to Us

The best thing about the product is the added safety that it ensures. In this modern world, people are getting more and more aware of the growing health concerns. Most people shift from traditional to electrical tanks because they offer better safety. This model eliminates any bacterial growth and thus keeps the inside of the machine secure and safe for usage.

Who Will Use This Most

For people looking for more durable options, this is definitely the right product. The construction of the product is one of its strongest features. The copper heating elements have been used with brass termination in the making of this product. This will allow better durability for people who want longevity in their products.

Bottom Line

Safety, comfort, and higher reliability come together in the making of this amazing tankless water heater. The product has a high-temperature adjustment range, which makes it a favorite among consumers. It also allows for easy installation, thanks to its sleek and efficient design. That’s not all; the Eemax unit will also help keep you and your family secure from the harm of any sedimentation or bacterial infection.

Best Marey Electric Tankless Water Heater:
Marey Power Pak Plus

Marey Power Pak Plus Tankless Electric Water Heater, 220 VOLT


  • Installation is very easy
  • Easy to manage and adjust
  • Saves on both money and energy
  • Only requires very low pressure of water for activation
  • Does not allow sediments to grow on the water heating


  • Less max input temperature level
  • Might lead to overloading of the circuit
  • Requires greater voltage to run than some other models

What Recent Buyers Report

Recent buyers are happy with the performance of the product because it allows them to regulate energy consumption, thus adapting the product to the electrical capacity of their home. But that’s not all. The product is also considered reliable as it requires very low pressure for the activation process. Moreover, it saves energy and money, thus appealing to consumers more.

Why it Stands Out to Us

The best thing about this model is its distinct ability to be wired at a range of different amperes. This includes 10, 20, 30, and 40 Amperes. This feature is not found in any of the other models on the market and hence makes it stand out. By wiring the product to different units, you can easily limit the power setting that you want to use for the heater.

Who Will Use This Most

The product is best for people who are looking for compact and lightweight units to install in their homes or offices. It is also ideal for a one or 2 bedroom house in a tropical or semi-tropical climate. Moreover, where temperatures are very low, this heater would be better suited to be used for a single purpose only. This will not only ensure optimum performance but will also allow you to get consistently hot water at all times.

Bottom Line

Marey has proudly been in the industry for the last 7 to 8 decades, but that’s not the only reason for its popularity. It has brought forth innovative products with better features like greater mounting diversity and wiring options. Moreover, it comes in a sleek design for more convenience.

Best Bosch Electric Tankless Water Heater:
 Bosch Electric Tankless Water Heater 17.3 kW

Bosch Electric Tankless Water Heater - Eliminate Time for Hot Water - Easy Installation, 17.3 kW


  • Comes with a relatively lower stand by loss
  • Has a built-in flow sensor for consistent results
  • Comes with a control knob that is fitted externally
  • Suitable for both residential and commercial purposes
  • Allows for easy installation and can be installed anywhere


  • Not cost-efficient
  • Heavier than most models on the market
  • Difficult to replace parts in case of breakage

What Recent Buyers Report

Recent buyers have written extremely positive reviews for this product, and owing to its huge popularity is its higher energy-efficient technology and easy installation feature. The Bosch can last for more than 12 years and hence considered to be one of the most reliable products on the market. Not just that, if properly maintained, it can also generate a life expectancy of 20+ years.

Why it Stands Out to Us

The best thing about this heater is definitely its ability to be consistent in its results. With this model, you won’t have to worry about getting varying levels of water temperature across different appliances. The superior technology of the product allows you to get the same consistent temperatures on more than 3 appliances, at the same time.

Who Will Use This Most

The model comes with a functional flow sensor that detects the temperature of water required, thus giving you consistent output temperatures at all times. This feature makes the model a perfect fit for small and medium-sized families who use more than one water appliance at the same time. Moreover, its element modulation technology also adds to the stability and provides you with higher control.

Bottom Line

This product has certainly been a game-changer in the industry. It is a product loved and respected by nearly everyone who has bought it. It comes with an easy-to-use knob that allows you to control the temperature of the water. Not just this, it also allows for a relatively lower stand by loss, thus ensuring that you save on energy.

Pros and Cons of Electric Tankless Water Heaters

With any product, you can expect a fairly equal number of pros and cons, but the case is slightly different when it comes to tankless heaters. They come with a fairly large number of pros and very few cons. Let’s look at them all.


An electric tankless water heater comes with the following benefits:


With electrical products, you expect greater consistency, and that is exactly what the product ensures. All these products in this review will ensure you get a consistent supply of hot water at all times.

Energy Efficiency

The product does not produce any greenhouse gas, thus making it environment-friendly. Moreover, it is also considered energy efficient as it usually saves more than 60% of the energy otherwise consumed by a tank water heater.

Easy Installation

Effective and quick installation is the first step to convenience, and that is exactly what these products ensure. Tankless heaters do not require any venting or difficult procedural installation, thus making it easier to install them.

Longer Lifespan

Traditional tanks that are normally used do not last very long; they either get damaged by external factors or are contaminated by bacteria. Electric heaters are free from all these issues and can last for up to 20 years.


The downsides of tankless water heaters are few, but include:

Higher Cost

This is an issue that many people face as the installation, as well as maintenance of these tankless heaters, is costly. The initial cost isn’t too low, either, thus acting as a deterrent for many people buying them.

Lowered Water Flow

Natural gas heaters have a greater water flow because they have more power than electric heaters; thus, many people don’t like investing in these.

How to Install an Electric Tankless Water Heater

Installation is often not very hard when it comes to electric tankless heaters. You simply have to follow some easy steps, and you are good to go. Here is a list of what you have to do. You need to identify the main power panel or the application fixture near which the tankless heater needs to be installed; if you intend to install the product inside, then it better be near a power source.

  1. The distance between the heater and the tap also affects the time taken for hot water to come in, so ensure that the distance is not too great for frequently used taps.

  2. A long wait line will add to your electricity bill, so make sure you pick the right spot for the installation. The lesser the distance, the quicker the hot water flow will be.

  3. You will require more wiring and faucets if you install the product very far from the taps. This will obviously add to the additional cost.

  4. Install it vertically on the wall and keep the buttons on the bottom.

  5. Remove the front cover carefully and disconnect the white material attaching the panel to the button inside.

  6. Connect the power supply at the lower end side of the unit.

  7. Tighten the screws for added safety.

  8. Connect the two knobs at the bottom with a suitable hose.

  9. Switch the breaker connections once the installation is done.

  10. Add the front cover back on.

Make sure to refer to the video below for a full overview of what was just described to be clear on the installation.


Tankless water heaters are the new thing, and people love them. So if you want to free yourself from the hassle of waiting for consistently hot water each time you open the tap, then get yourself a good tankless electric heater. It will not only be light on your pockets but will also give you additional features like more safety, reliability, and energy efficiency.

People Also Ask

This review explains almost everything that you need to make an informed decision. However, to better aid our purpose of helping you out, we have tried to respond to the most frequent questions asked by recent buyers right here.

Do Electric Tankless Water Heaters Need a Vent?

Contrary to what a lot of people think, electric heaters, especially tankless ones, do not require any sort of venting. They do require a lot of electricity, but that’s about it. The no-venting feature makes it easy to install and mount. And although they don’t require venting, they still need a small amount of space around their unit to function properly.

How Do You Hook up an Electric Tankless Water Heater?

Anyone can hook the heater up by mounting it and installing it inside the unit. You can do this by reading the instructions written above. The best thing about these heaters is that they can heat water without needing any storage tank. When you turn on the tap water, cold water will travel through the pipe in the unit and will get warmed. This will allow a constant supply of hot water.

How Long Do Electric Tankless Water Heaters Last?

That’s a question whose answer will vary depending upon how carefully you use the appliance. Most tankless heaters come with a life expectancy of around 20 years. They also come with replaceable parts that further increase their life expectancies. If not properly cared for, your tankless heater can wither away within 10-15 years too.

How Many Amps Does an Electric Tankless Water heater Draw?

The biggest drawback to getting yourself a tankless electric heater is the additional electricity it requires for running. Nearly all models require at least 120 A of electricity to operate. If you require a bigger heater, then you will have to invest more in the model. The upgraded model will obviously require amperes up to 200.

What Size Breaker Do I Need For a Tankless Water Heater?

For an ordinary tankless heater, you will have to buy a breaker of 40-50 ampere for each of its wires. Each wire will be able to supply only one element. Hence if you have 3 elements, you will require a breaker 120 amperes at least.

Need to Hire a Plumber for a Water Heater?
Get help from a qualified plumber in your area now!

My name is Bob Wells and I am a retired HVAC tech from Washington state. I am currently retired and no longer do much with HVAC, however, I feel like I have a lot of knowledge in the subject and I wanted to create a website where I could talk about what I've learned and help upcoming HVAC techs. Find more info about me and HVAC Training 101.