How to Remove Water Heater Pressure Relief Valve
- 1). Turn off the heater by disconnecting the power if the heater is electric or by turning the thermostat all the way down if the heater is gas.
- 2). Turn on a hot water faucet in a sink or tub to run the hot water out of the water heater tank. When the water turns cold, turn the faucet off and turn the cold water line off at the heater by turning the pipe knob to "off."
- 3). Release the water pressure from the water heater tank by raising the lever on the pressure relief valve; this will cause the water to flow out of the overflow pipe.
- 4). Place a bucket under the overflow pipe and allow the tank to drain until the water stops flowing. When the water stops flowing, close the pressure relief valve.
- 5). Use a large pipe wrench to unscrew the overflow pipe from the pressure relief valve. Unscrew the pressure relief valve from the heater using the large pipe wrench and turning the valve counterclockwise. Extreme force may be necessary if the pressure relief valve is very old. Be careful not to damage any electrical wires or water pipes when removing the pressure relief valve from the water heater.
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