Locate the water heater thermostat or temperature dial
Turn off power to an electric water heater before adjusting
For a gas water heater, remove the access panel if needed
Increase the thermostat setting slightly
Set the temperature to about 120°F to 140°F
Replace any covers or access panels
Restore power or relight the pilot if necessary
Wait several hours for the water to heat
Test the hot water at a faucet
Adjust again if needed
Check for scald risk before setting the temperature higher