Best Whole House Electric Tankless Water Heater Review

We live in times of instant gratification. Why should water be any different? Buying the best whole house electric tankless water heater makes life much easier. First, you get almost instantaneous hot water. Second, with a tankless water heater, you get an endless supply of hot water. So you don’t have to schedule your morning around hot water supply or save some for others.

A tankless electric water heater is a long term purchase. Not all water heaters have the capacity to supply hot water for the whole house. Watch out for the kW capacity. We all like our water to be just right. Minute temperature control is high on the desirability scale. Factors like thermal efficiency, durability and ease of installation are important considerations as well. Based on these salient features we have enlisted the best electric tankless water heater. Peruse away.

Best Whole House Electric Tankless Water Heater Review

Best Whole House Electric Tankless Water Heater

  1. Thermoflox Elex 15

Convenience and savings are of extreme importance to domestic users. This German tech fitted tankless water heater provides instant heated water. With free bare wire heating systems, the water is heated right up to the faucets. At a heating speed of 3.5 gallons per minute, you will never run out of hot water. If you are someone always in a hurry, this is the best whole house electric tankless water heater. Because of its compact size, it hardly takes any space. You can conveniently tuck it away in a corner.

The German tech used in the Thermoflox makes standby losses and preheating a thing of the past. It’s 15 kW capacity is perfect for a small family and apartment. This is a great option for someone getting their first electric water heater.


  • Power saving
  • Compact size
  • Instant heating


  • For smaller apartments only
  1. Bosch Electric Tankless Water Heater

Bosch has been a household name for a long time for its quality products. At 17.3 kW it is in the same capacity range as the earlier entry on the list. But this also comes with an option of higher capacity at 26.9 kW. They both provide the same results depending on the size of the house or office. It can be easily wall-mounted, out of your sight quietly doing its job to perfection.

You get hot water on demand in 2 – 3 outlets at the same time. You don’t have to alternate doing the dishes and taking a bath. As a top contender for best whole house electric tankless water heater, Bosch takes its saving seriously. Both in power and durability, with up to 20 years of operational expectancy.


  • Multiple power variants
  • Long life


  • Installation could need professional assistance
  1. Ecosmart ECO 35kw

With near perfect 99.8% thermal efficiency, this one leads the pack on our list. Capacity is key for best whole house electric tankless water heater. Even though most claim to be tankless water heater for the whole house, the kW just doesn’t back it up. At 35 kW, the ECO can supply hot water to the whole house at up to 4 outlets at a time. This impressive heating performance is not compromised by extreme cold either.

The intelligent self-modulating technology allows the heater to customize energy usage to water consumption pattern. This allows it to save a ton of money on electricity bills. This is where it derives it’s a very apt name. The copper and stainless-steel components are both durable and easily replaceable.


  • Easily replaceable parts
  • 8& thermal efficiency


  • Could be overkill for small apartments
  1. Ecosmart ECO 18kW

While its 35 kW counterpart is perfect for large homes, this one is perfect for a small household. Higher kW does not mean the best electric tankless water heater. You have to choose the right one according to your consumption. The water supply is both instant and endless at the legendary 99.8% thermal efficiency. It is easy to install and has a small form factor to hang as desired on any wall.

Control is as is important as heating for the best tankless water heater. The elegant and easy to use digital temperature control that you can manage by the degree. It also has a self-modulating temperature controls system. It only uses energy when needed, slashing the bill by up to 60%.


  • 8& thermal efficiency
  • Increased energy efficacy by 60%


  • Not ideal for large houses
  1. Stiebel Eltron Tempra 15 Plus

The Tempra is another proud entry to the 99% thermal efficiency club. This is the most expensive entry on or list but it is worth the money. Often opening multiple taps means colder water from all the taps. But water dispensed from Eltron ensures all taps maintain the same high temperature. Even when used simultaneously. It is both easy to install and takes minimal space. It is also silent as a mouse. Even if you install it inside the house there will be no irritating noise.

The fact that it is German is a testament to its quality. The best whole house electric tankless water heater has to have reliability on its side. Despite the high-quality parts, the Tempra comes with a 7-year leakage and 3-year parts warranty. Now that’s faith in your product.


  • Warranty on parts and leakage
  • 99 % thermal efficiency


  • Higher on the price scale

Frequently Asked Questions

  1. Are electric tankless water heaters worth it?

In one word, absolutely. That is if you understand your heating requirements. They are much smaller than they’re with tank counterparts. They need less planning, because you don’t have to wait for the water to heat up. It’s all about knowing what to look for and the quality. There are plenty of good options, some listed right below. Read: Best Whole House Water Filter for Well Water

  1. Is electric tankless water heater better than tank?

‘Better’ might not be the best word, but tankless water heaters sure do have their advantages. The water supply is more or less instantaneous. But what sets it apart is the endless supply of hot water. You don’t have to worry about running out of hot water mid bath ever.


We have some great options listed here for anyone looking for a tankless electric water heater. We have coalited all the relevant information and the top choices for you. Understand your average weather condition, space, plumbing requirements and water consumption patterns. Knowing your needs is the key to finding the best whole house electric tankless water heater. After that, making an informed decision comes easy.