What Size Electric Tankless Water Heater Do I Need For a Shower

tankless electric water heaters

When looking for an electric tankless water heater, it is wise that you consider some basic factors like size and design. Buying can be simple, but choosing a good tankless water heater goes beyond market assessment. This is because of the different choices available in the market and choosing good ones from normal ones to depend on the kind of guide you are using. And when guides and buyers’ tips are required to help our readers make a wise choice, we provide guides and fundamental operations to your water heaters. So, before making any move towards buying, it is prudent you understand some basics, and to help you understand them better, hold on the guide got your next purchase.

What Size Electric Tankless Water Heater Do I Need for a Shower?

tankless electric water heaters

Before you pick an electric tankless water heater, it is wise to consider the size of your home and the day to day applications. The guide will try to outline the right brand size for a given home tankless heater to buy. The guide below is based on a random application, and you can use it when choosing which size of a tankless heater to buy.

  • For two people with high water usage, you will require an electric heater rated at 40-50 gallons. Under regular water usage, you will require an electric heater size rated at 30 gallons.
  • 3-4 people under a regular or low hot water usage your heater should be rated at 50 gallons, under a high-water usage you will require an electric heater rated at 60 gallons.
  • 5-7 people under a regular and low water usage, your electric heating system should be at least 60 gallons heating ability, but if they are high water users, then your electric heater should have an 80-gallon ability.
  • Lastly, more than seven people under regular or low water usage, your electric size should be at least 90 gallons, and if they are high users, then your electric size should be 120 gallons.

Tankless heaters are designed to provide you with automatic heated water for your shower and other household applications anytime you need hot water. The endless and instant flow of hot steamed water, lower electric bills, simple installations, cheaper maintenance cost, durability, tax breaks, and extended warranties are some of the key reasons you need a water heater in your commercial and residential buildings. Perhaps the main reason is that heaters are customized to save your house space.

What Size 120v Electric Tankless Water Heater Do I Need for a Shower?

For a 120v electric tankless water heater, the size can vary depending on the day to day applications. For universal standards to install in your shower for people who always have two showers a day that is in the morning and in the evening after work, a good and ideal choice is the one with 5-gallon heating ability, rated at 5 gallons per minutes. If you are using your heater to run other activities like a washing machine and warming the house, then the size can increase to 10 gallons per minute.

Each brand under 120v has its own application on size, and the application getting it right from your user manual plays a key role in having the right heater for your home. As they say, buying is easy, but picking the right heater requires more than giving out cash, and for our instant is to ensure you have the right size for your task.

What Size Electric Tankless Water Heater Needed for Bathroom with Shower Plus Laundry Room?

best tankless water heater electric powered

With an additional task on your tankless hot water system, the size is also expected to increase from the normal shower size of 5 gallons per minute to a larger number for both efficiencies and to avoid power consumption. Tankless designers and real estate suggest that a water heater subjected to both laundry and showers should be at least 15 gallons per minute rated. But due to the advancement of different heaters with a higher resistance value that achieves the heating over a shorter period, this can be reduced to 10 gallons per minute.

Other Considerations

The whole thing depends on the brand and type of the tankless heating system you but. Above all, the rating and user manual should shine a light on the heater applications and the right size. It is wise to understand that each tankless heater has a different heating ability, and the only way out is to find more about what you have just bought in the user’s manual. The guide finding s are based on the universal standards recommended by real estate on the bathroom heating system on the right size of heating system to install in your bathrooms with the aim of getting warm water and hot water supply. It is wise to consider the size and ability of the heater before making any move towards buying as this play a key role in all its application for any home if you are to get a continuous supply of warm and hot water.

Where is a Bosch Tankless Electric Water Heater for a Shower Installed?

Provided your Bosch tankless heater is equipped with enough vent for combustion, you can install it in a utility room, basement, attic, garage or somewhere outside the wall. The Bosch can also be installed in a space where a reservoir-based heater can not provide an ideal fit, like in bathroom or bedroom. You can also find more places where you can have your heater installed. Also, other factors come into consideration when choosing the right place to install your heater.

Bosch Electric Tankless Water Heater Recommend


Buying can be simple and normal in our market full of choices, and with guides online, securing the best heater is even easier. But applying the whole concept that will ensure you get the best size your heater requires more, and our guide always finds a way to ensure you have what it takes for a good and proper function. Our findings are based on the universal application of heating systems to install in your home.


David: Penn State-educated Mechanical Engineer and Business-savvy Fluid Dynamics Specialist. Balances family plumbing business support with a thriving engineering career at a top, undisclosed company. (they want it that way) I help Will with plumbing and HVAC needs on his Real Estate.

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