The temperature and pressure relief valve on a gas water heater is a safety feature that prevents the interior temperatures from becoming too hot or from too much pressure building up, which can cause the tank to explode. When the relief valve is starting to fail, you might notice a leak starting from that area of the heater.
Replacing the valve is a short process, but you need to ensure the valve is fully tightened or your tank could explode. If you have any doubts whatsoever, call in a water heater repair company to replace the valve for you.
Things You Need:
- Garden hose
- Flat-head screwdriver
- Pipe wrench
- Plumber's sealant
Step 1: Drain the Water Heater
Unplug the water heater's electrical cord from the wall socket. Shut off the gas supply to the water heater by twisting the shut-off valve on the supply line, then do the same to the shut-off valve on the water inlet line.
Locate the drain valve near the bottom of the water heater. Screw one end of a regular garden hose onto the drain valve's threads then place the remaining hose end over a floor drain or sink. Open the drain valve with a flat-head screwdriver, which will allow water to start draining out of the water heater. Stand clear of the draining end of the hose as the water can be quite hot.
Wait until about half of the water has drained from the tank then use the screwdriver to close the valve. Detach the hose.
Step 2: Remove the Old Temperature and Pressure Relief Valve
Locate the temperature and pressure relief valve. Remove any surrounding insulation, if applicable, which should simply be able to be pulled off. Use a pipe wrench to loosen the discharge tube leading up into the relief valve. Pull the tube off the valve and set the tube aside for later re-installation.
Use the pipe wrench to twist off the relief valve, working in a counterclockwise direction. Pull the relief valve out of the water heater and discard the valve.
Step 3: Install the New Temperature and Pressure Relief Valve
Install the new temperature and pressure relief valve by sticking the end through the vacated hole in the water heater. Thread the valve into place, turning in a clockwise direction. You can get the valve started by hand, but then you will want to finish up with the pipe wrench to ensure the valve is fully secured. Make sure the orientation ends with the threaded hole for attaching the tube pointed down.
Use your finger to apply a thin coat of plumber's sealant to the grooved end of the discharge tube. Thread the tube onto the valve using your hand and the wrench. Put the insulation back around the valve, if there was insulation. Double check to make sure the drain valve is fully closed.
Turn on the shut-off switches on the gas and water supply lines. Plug the water heater back into the electrical socket. Allow the tank time to fill up and reheat before testing the water at one of your sinks. Contact a company like Johnny Pipewrench LLC for more info or assistance.