How to Replace the Thermostat in an Electric Hot Water Tank
- 1). Turn off the electric supply for the water heater at the breaker box.
- 2). Using a Philips screwdriver, remove the cover on the water heater, exposing the thermostat.
- 3). Use a voltage meter to make sure the electricity is turned off to the water heater, otherwise serious injury can occur.
- 4). Disconnect the wires from the thermostat terminals using the Philips screwdriver. Take note of the wire location and the color of each wire.
- 5). Install the new thermostat and match up the color and location of the wires from the original thermostat, securing the wires to the terminals of the new thermostat using a Philips screwdriver.
- 6). Replace the cover to the water heater and turn the breaker back on. Observe the water heater in operation to ensure that the thermostat is set at the correct temperature.
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