Many water heater thermostat manufacturers ship products that are preset at 140 degrees Fahrenheit, but most of us don't need water that hot. In fact, 120 degrees Fahrenheit is sufficient for most households. As long as your shower is hot, will you notice the difference? Probably not — until your energy bills arrive. According to the U.S. Department of Energy, lowering your water temperature 10 degrees Fahrenheit will lower your energy costs by 3 to 5 percent.
Lowering the water temperature to 120 degrees Fahrenheit also helps your water heater run at its most efficient levels by keeping down corrosion and sediment build-up.
Tip: Dishwasher cleaning cycles should be run with 140 F degree water. If your dishwasher has a booster heater, lower your water heater thermostat without worry. If your dishwasher doesn't have this feature, this tip may not be for you.