Running Out of Hot Water Too Fast

Likely causes, most common first

1. Failed lower heating element on an electric unit
2. Sediment filling part of the tank, which leaves less room for hot water
3. Broken dip tube, which sends cold water to the top of the tank
4. Thermostat set too low or out of calibration
5. Burner problems on a gas unit
6. A unit that is too small for the household now using it

What you can safely check

1. Check the thermostat setting against the unit's label.
2. Electric: check the breaker.
3. Note how long the hot water lasts and whether it goes lukewarm or cold first.
4. Look at the tank and pipes for leaks.

What not to do

• Do not set the thermostat above the unit's safe maximum.
• Do not remove panels on an electric heater with the breaker on.
• Do not ignore small plastic pieces in faucet screens. They can come from a broken dip tube.

When to call a professional

Call if the problem started suddenly, the water has been getting steadily worse, there is rust or sediment in the hot water, or the unit is old. We test the elements, thermostat, burner and dip tube to find the cause.

Related service: water heater repair.