Best Temperature for Water Heater

Water heater thermostat

Last Updated: 9/16/2023

Many homeowners wonder: what is the best temperature to set the water heater? This is a great question, and with the following information from Aire Serv®, you can maximize the performance, efficiency, and safety of your water heater.

Determine the Best Temperature for Your Water Heater

The standard temperature for most water heaters is 140 degrees F, but the Department of Energy recommends turning down the temperature to 120 degrees to save energy. Just remember – any setting below 120 degrees increases bacteria growth inside the tank, so you shouldn’t go any lower than this (unless you’re going out of town, in which case the DOE recommends turning down the thermostat to the lowest setting).

Consider the variables that affect what temperature you should set your water heater:

  • Your dishwasher: If your dishwasher doesn’t have a booster heater, you may want to keep your water heater at 140 degrees for optimum cleaning. However, this feature is found on most modern dishwashers. Check your owner’s manual for more information.
  • Your health: While the bacteria growth inside a tank set to 120 degrees is safe for most people, you should consider keeping yours at 140 degrees if you have a suppressed immune system.
  • The number of people in your home: If you live alone, it’s unlikely you’ll ever run out of hot water when you keep the tank at 120 degrees. However, if six family members shower back-to-back each morning, the extra 20 degrees helps ensure hot water for everyone.
  • Whether you have children: Setting your water heater to 120 degrees reduces the risk of scalding at the tap, which is especially important if you have kids or older adults living with you.

How to Adjust the Water Heater Temperature

Perhaps you want to help your dishwasher do its job better by turning up the water heater, or you’re hoping to reduce scalding by lowering the temperature. Either way, follow these instructions to adjust the water heater setting:

  • Measure the current temperature: To get an accurate reading, turn on the hot water at a faucet located furthest from the water heater. Place a thermostat under the running water to discover if an adjustment is necessary.
  • Locate the thermostat dial: Gas water heater tanks have dials near the bottom of the tank. Electric water heaters often have thermostats positioned behind screw-on panels. There might be two dials if your electric water heater has upper and lower heating elements.
  • Measure and adjust the setting: Turn the thermostat up or down slightly from its starting position. Then, wait a couple of hours. Measure the water temperature again and make more adjustments as needed. When you’re satisfied, mark the final temperature on the dial so you can easily modify the setting again in the future.

Other Ways to Improve Water Heater Efficiency

In addition to setting the temperature back, you can make these home energy improvements to decrease your water heating bills:

  • Insulate the water heater tank to reduce standby heat loss.
  • Replace your showerheads and faucets with low-flow versions that consume less hot water.
  • Install a tankless water heater that heats water on demand to eliminate the need for storage and the resulting standby heat loss.

Schedule Water Heater Services with Aire Serv®

Whether you need help adjusting the water heater temperature, or you want to schedule water heater repair or replacement, trust Aire Serv for the job. We’ll help you save by performing comprehensive repair services and replacing your water heater when it reaches the end of its lifespan.

To schedule water heater services with a skilled technician, please contact Aire Serv today!