The average household will spend between $400-600 each year on water heating. That makes it the second largest expense for you home, accounting for 14-18 percent of your utility bills, according to the Department of Energy. However, you could pay more by setting your water heater temperature too high.

Many manufacturers will set water heater thermostats at 140 degrees Fahrenheit, but many households might set them lower at 120 degrees Fahrenheit. Setting your water heater temperature too high can cost $36-61 a year in standby heat loss, plus an additional $400 in demand losses. 

So, is it necessary for your water heater to be at 140 degrees F, or can your household get by on dropping it down to 120? That depends on how much water your home uses, what you use that water for, and the appliances in your house.

If you have a dishwasher that does not have a booster heater, then it might require your water temperature to be between 130-140 degrees F for optimum cleaning. The Department of Energy also says that while there may still be a small risk of promoting bacteria when water heaters are at 120 degrees F, we still consider this level safe for most of the population.

Elderly homeowners, or those with small children, may want to keep their temperatures at the lower 120 degrees F. It can take only two seconds for a child to receive third-degree burns from water that is 150 degrees, and just five seconds if it is at 140 degrees.

Health reasons may encourage you to keep your water heater temperature higher, though. If you or someone in your home has a suppressed immune system or chronic respiratory disease, then your water heater should remain at 140 degrees.

You can easily find your water heater’s temperature by checking the dial on the water heater or taking a temperature reading from the faucet. If you are pleased with its current temperature, then there is no need for a change. If you live in a larger household, where water usage increases, then a higher temperature will help accommodate the demand. 

When you are looking to lower the temperature for any reason, then dropping it down to 120 degrees should not be an issue. If it does not feel as warm as you want it to, you can always go back and increase the heat incrementally until you find that perfect temperature.

Adjusting the thermostat on your water heater is a simple task, but when you have larger problems or a plumbing emergency, call Keller Plumbing at 616-866-5134.