What Is The Best Temperature Setting For A Water Heater?


What Temperature Should a Hot Water Heater Be Set At?


Your water heater accounts for about 18 percent of the energy bill for your house. If your water heater is set too high, your energy bill will pay you the price every month. If your water heater is set too low on the flip side, your water may not get hot enough (short showers), or worse, maybe at risk for bacteria to grow. Do not set your water heater to anything below 120 degrees, as diseases that grow inside the water heater, particularly Legionella, which is quite dangerous in the stagnant water.


What is your water heater's optimal temperature range, then? The EPA recommends 120 degrees because it is hot enough to hold illness at bay, it is not hot enough to cause scalding, it will provide enough hot water for most small families and it is fairly energy-efficient. The best setting for you might, however, vary based on a few factors.


Factors That Affect Hot Water Temperature Setting


Such considerations are not influenced by the type of plumbing you have (PEX, PVC or copper), how the water is heated (gas or electric) or even if you have a hot water heater with tankless heating.


  • Homeowners with a dishwasher that does not pre-heat the water may want to set their water heater to 140 degrees.

  • Elderly homeowners or those with small children may want to keep the temperature at 120 degrees. According to BabyCenter.com, “It takes just two seconds for a child to receive third-degree burns from water that is 150 degrees and five seconds if it is 140 degrees, the temperatures at which hot water heaters often leave the factory.”

  • Homes with residents having an immune system or respiratory disease suppressed will keep the hot water set at 140 degrees.

  • Generally, many who live alone are striving for a lower temperature in the acceptable range since there is less competition for hot water, and it saves money. Many who live in large households strive to a higher temperature to satisfy increased hot water demand.

  • If you want to save money, every 10 degrees you turn down the water tank thermometer, you save 3 to 5 percent on your energy bill.


Still undecided? Set it at 120 degrees and increase the temperature in small increments until you find the perfect shower temperature.




By looking at the dial on the water heater (if equipped) or taking a temperature reading from the faucet you will find your current temperature setting. Turn on the hot water tap and let it run for a couple of minutes before the temperature is taken.




If you are concerned about bacteria in your hot water and are worried about scalding water, find a booster for hot water tanks. It keeps the water in the tank at 140 degrees but mixes it with cold water to bring down the temperature to 120 degrees before it hits the tap.


When you live in a large home where hot water takes a long time to hit the tap, that can be fixed by a hot water circulation device. The machine slowly circulates hot water in the pipes so that it does not cool down before it hits the tap.

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