Troubleshooting Water Heater Element Resistance
- 1). Turn off the breaker for the water heater at the main panel.
- 2). Remove the screws holding the access panel doors to the water heater. Most water heaters with a 30-gallon capacity and above have two access panels located on the side of the water tank at the top and bottom. Remove the access doors and any insulation from behind them.
- 3). Pull the thermostat covers from the face of the thermostats and heating elements. The covers snap on and off and are not held by any other attaching device.
- 4). Test the water heater for electrical current to confirm the correct breaker was turned off. Set a multimeter to 250 AC (alternating current), and touch a prong from the meter to a terminal screw holding a wire above the red reset button at the top of the thermostat. Touch the other prong to the metal body of the water heater. If you turned off the correct breaker, the needle on the multimeter should not move.
- 5). Loosen the two screws on the heating element. Pull the wires from beneath the two screws.
- 6). Turn the dial on the multimeter to Rx1 (resistance times 1000), and touch a prong from the multimeter to each screw. If the needle moves all the way to the right on the multimeter, the element is still operational. If the needle does not move, the element has failed and needs to be replaced.
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