Why your water heater keeps tripping the breaker

Breaker or reset button?

They're two different things. The breaker is in your electrical panel and trips when too much current flows, usually from a short. The red reset button sits on the heater behind the upper access panel and trips when the water gets too hot. If the heater's reset keeps tripping instead, see how to reset a water heater.

Gas water heaters with a standing pilot don't run on a big electrical circuit, so this guide is about electric tanks.

A shorted element

A heating element that has cracked or burned out can short to the tank. Bradford White's test is simple: with the power off and the wires removed, put one tester probe on an element terminal and the other on the element flange or tank. Continuity there means the element is grounded and has to be replaced. Our guide to a bad electric water heater element covers the other element tests.

An element that shorts within seconds of power coming on, right after the tank was drained or replaced, was probably dry-fired. Bradford White says an element exposed to air in the tank burns out in seconds, shows a melted or copper-colored sheath, and isn't covered by warranty. Always open a hot water tap and wait for steady water before turning the breaker on.

Wiring and loose connections

Lennox lists loose or corroded wiring among the common causes. A connection that's loose at the element, the thermostat or the junction box on top of the heater heats up every time the heater runs. Look for scorch marks, melted insulation or a burnt smell, but only after the breaker is off. Water dripping onto the wiring from a leaking fitting or an element gasket can trip the breaker too, so check for wet spots around the access panels.

A circuit that's too small

The National Electrical Code requires the branch circuit for a storage water heater to be rated at no less than 125% of the heater's rating. A heater swapped for a bigger model, or wired onto a circuit sized for the old one, can trip under a normal load. The rating plate on the tank lists the wattage and voltage, and an electrician can check it against the breaker and wire size.

What to do

• Reset the breaker once. If it trips again right away, leave it off.
• Don't tape or hold the breaker on, and don't swap in a bigger breaker. The breaker is sized to the wire.
• If you see water near the wiring, fix the leak first.
• If an element tests grounded, replacing it is a common repair. If the tank is also old and leaking, compare the cost with a new heater.

Electric water heating is common in some areas we cover. About 24% of homes in Weymouth, Massachusetts heat with electricity (see our Weymouth page), and Fort Collins, Colorado runs its own electric utility (see our Fort Collins page).

Local pages mentioned

• Fort Collins, CO
• Weymouth, MA