Water Heater Keeps Tripping the Breaker? Causes and What to Do

An electric water heater most often trips its breaker because a heating element has failed or shorted. Other causes include damaged wiring, moisture, a faulty thermostat or an overloaded circuit. Switch the heater off at the breaker, do not keep resetting it, and have a licensed plumber or electrician test the elements.

Water and electricity share this appliance, so a trip is worth taking seriously. The sources below are plumbing and HVAC company guides and a forum thread, so treat them as general guidance.

Common causes

• Failed heating element. A degraded element can short inside itself or draw more current than its rating. Mineral buildup can make it overheat and fail.
• Ground fault. Current leaks to ground through faulty insulation or moisture.
• Damaged wiring. Worn insulation or a loose connection at the terminals.
• Faulty thermostat. It can leave an element on when it should switch off.
• Sediment. Buildup on the elements makes them work harder.
• Undersized or overloaded circuit. The breaker must match the heater's rating.

How to fix it

1. Turn off the breaker and leave it off. Do not keep resetting it.
2. Look for leaks around the tank, fittings and the access panels. See the signs of leaks you cannot see if you find damp spots.
3. Check the breaker rating against the label on the water heater.
4. Call a professional to test the elements and thermostats with a multimeter. A faulty element typically reads open (infinite resistance) or near zero ohms.
5. Replace the failed part, or the heater if the tank is old or leaking.
6. Flush the tank to remove sediment if a professional recommends it.

When to call a professional

• The breaker trips right away every time.
• You see water, rust or scorch marks near the tank or wiring.
• The unit is old or the tank is leaking.
• You smell burning.

No hot water in the meantime? See hot water problems in cold weather.

What not to do

• Do not install a bigger breaker.
• Do not reset the breaker repeatedly.
• Do not open panels with the power on.
• Do not ignore signs of a ground fault.

Bottom line

Switch it off, leave it off and get the elements and wiring tested. A failed element is a common and fixable cause, but it is not a safe DIY job unless you are trained. If you lose power to more than the heater, see staying safe if the power goes out.