Hot Water Heater Not Working
No hot water is usually caused by a tripped thermostat reset button (electric), a pilot light that's gone out (gas), or a failed heating element. Most of these are fixable without a plumber.
Step-by-Step Fix
- 1
Check the power source
Electric: check your breaker panel for a tripped breaker labeled 'water heater' — reset it if tripped. Gas: make sure the gas valve to the heater is open (handle parallel to the pipe = open).
- 2
Relight a gas pilot light
Set the thermostat knob to PILOT. Push and hold the pilot button (or knob) and use a long lighter to ignite the pilot flame. Hold the button for 30–60 seconds after the flame lights, then release. Set the thermostat to your desired temperature (120°F is standard).
- 3
Reset the high-limit switch (electric)
On electric water heaters, there's a red reset button behind the upper access panel (usually two panels on the side). Remove the panel, press the red button firmly until you hear a click, replace the panel, and wait 30–60 minutes for water to reheat.
- 4
Test the heating element (electric)
If resetting didn't help, a heating element may be burned out. With power off at the breaker, use a multimeter set to ohms — test each element by touching probes to its two screws. A reading of 10–30 ohms is good; OL or infinite ohms means it's bad and needs replacing.
- 5
Check the thermostat setting
Both gas and electric heaters have thermostats — ensure they're set to at least 120°F. On gas units, the dial is on the front of the gas valve. On electric, it's behind the access panels.
⚠️ Safety Notes
- If you smell gas near the water heater, leave the house immediately and call your gas company — do not try to relight the pilot.
- Always turn off the breaker before removing access panels on an electric water heater.
- Water heaters over 10–12 years old may have multiple failing parts — repair costs can approach replacement cost.
When to Call a Pro
If the pilot won't stay lit after multiple attempts, you hear rumbling/popping sounds from the tank, or there's water pooling around the base, call a plumber. A leaking tank must be replaced.
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