What Temperature Should A Tankless Water Heater Be Set At?

What Temperature Should A Tankless Water Heater Be Set At?

Some guidance may be necessary if you’re unfamiliar with tankless water heaters. What distinguishes one tankless water heater from another? The question then becomes, which temperature is most appropriate for optimal performance of a tankless water heater?

The question you’re asking, let’s address it without delving into the past. The Consumer Product Safety Commission advises that water heaters, whether tank or tankless, should not exceed 120 degrees Fahrenheit.

Difference Between a Tankless and a Standard Water Heater.

Tankless Water heaters lack a storage tank and quickly elevate the water temperature. Such water heaters exclusively heat water when needed and refrain from storing it. Instead of using a tank, these appliances utilize water as it flows through the device, allowing it to heat up during the process.

Regardless of the number of people present in your house, you won’t experience a lack of hot water again.

Most water heaters store hot water in their tanks, maintained at the right temperature for immediate use. Turning the switch on results in hot water rushing into the tank.

Which Heater is More Affordable?

Consuming less energy, water heaters without a tank have an advantage. Unlike tank water heaters, the tankless kind doesn’t consistently operate to stabilize the water temperature in the tank. Instead, the tankless water heater warms the water when needed. This means the heater remains inert until you enter the home, initiate the dishwasher or shower.

For every dollar spent on fuel, a tankless water heater only wastes 82 cents. This contrasts with typical water heaters, which only return 60 cents on every dollar spent on water heating. There’s a notable divergence.

Also, Read: How Much Propane Does A Tankless Water Heater Use.

What Is the Optimal Water Heater Temperature?

If you don’t know much about tankless heaters, it’s normal to question if and how you can modify the temperature. Set the tank-style and tankless water heaters to 120 degrees.

In homes with elderly or young children, the heater temperature should not be higher than 120 degrees. 140-degree water can cause second or third-degree burns in a child as young as two seconds old. Before you buy a water heater, double-check the temperature setting. Some models are shipped with the temperature set to 140 degrees.

How low is too Low?

The water heater should be set to no less than 120 degrees Fahrenheit for safety and comfort. Cold water may make it more challenging to stay healthy and avoid getting sick if you or someone in your family has a weakened immune system.

Because the bacteria that cause Legionnaires’ disease may be able to survive at lower temperatures, raising the temperature is preferable. A lower temperature will only make showering or bathing more unpleasant.

ALso, Read: Can You Lay A Water Heater Down

How to Set A Temperature On a Hot Water Heater?

To change the temperature of your water heater, you only need to make a few simple adjustments.

  1. To begin, switch off the power to the water heater.
  2. To switch off the power in your home, utilize the circuit breaker on your electrical panel.
  3. To adjust the water temperature, locate the thermostat with the included screwdriver and turn the dial clockwise or counterclockwise.
  4. Reconnect the power, but wait at least an hour before bathing or showering to ensure the new temperature takes effect.

Which Factors Affect the Temperature Setting Of Heater?

Fuel Prices.

Setting your water heater to 120 degrees Fahrenheit is an excellent way to save energy without sacrificing comfort in your home. You can save money while still having hot water by setting your water heater’s thermostat to this temperature or one very close to it.

According to the EPA and the US Department of Energy, lowering the temperature of your water heater from 140 degrees Fahrenheit to 120 degrees Fahrenheit can save you 3 to 5 percent on your annual energy bill. A three-person household with an average electric water heater could save $7 per month.

Turn the thermostat down from 120 degrees to 118 and 119 degrees to save an additional 2%.

Also, Read: Can Cold Weather Affect Hot Water Heaters?


For a family, a temperature of 120 degrees Fahrenheit is recommended, which is warm enough for a bath or shower but not hot enough to produce third-degree burns or scalds. When adjusting the water heater’s temperature, people of all ages, especially the young and old, should proceed cautiously.

When the temperature in and around the house is around 110 degrees Fahrenheit, they feel safer and more at peace.

Machines For Washing Clothes.

When adjusting the water heater’s temperature, remember the other objects in the house that require hot water.

Most washing machines operate best at temperatures ranging from 120 to 140 degrees Fahrenheit. This strategy may help you to utilize less energy while still performing admirably. However, before making any modifications, read the manufacturer’s instructions for your washer.

Appliances for the Home.

Water heater thermostats should be adjusted between 120 and 140 degrees Fahrenheit for dishwashers and other home appliances to perform correctly. Because of this temperature range, these gadgets can survive longer and operate better.

Depending on the situation, the temperature setting on the water heater could make or break many different machines.


Even though you use it every day, your water heater is arguably the least-noticed appliance in your home. The ability to monitor the temperature of the water coming from your faucet and make modifications to preserve your family’s health and comfort. We hope that the transition phase is brief.

Choosing the appropriate setting for your water heater may save money on energy bills and avoid wasting water. Once you’ve worked it out, you can sit back, relax, and let it do its job for ten years.


What is the typical operating temperature of a tankless water heater?

The Department of Energy suggests setting your heater at 120°F. That should cover the majority of your family’s requirements.

At 140 degrees Fahrenheit, is a tankless water heater too hot?

Temperatures between 120 and 140 degrees Fahrenheit are considered safe. As a result, the decision is wholly personal.

What should a water heater’s maximum temperature be?

A temperature range of 120 to 140°F is suggested. However, the temperature of large water heaters in hospitals and industrial settings should be adjusted between 130 and 140°F. Set it at 120°F if you have children, which is safe for most people.

How long does a tankless water heater take to heat water?

A gas tankless water heater often takes substantially less time to heat than a conventional tank water heater. On-demand hot water from a tankless gas heater can save time and energy because it is often available in 15-20 seconds.


About Author

Mobeen Shahid

Mobeen Shahid

Mobeen Shahid is a Mechanical Engineer with two years of experience in the HVAC industry. His passion is analyzing HVAC issues, and he works relentlessly to devise customized solutions. He has been in the industry long enough to know the ins and outs and ensures that areas are optimally heated, cooled, and ventilated.

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