Working With Incredible Plumbers

How To Replace An Electric Water Heater Pressure Relief Valve

If the water isn't getting hot from your electric hot water heater, check for drips on the pressure relief valve, a brass fitting connected to a plastic dip tube. The pressure relief valve is a safety feature that thus the heater off in case the water gets too hot. You should be able to replace a relief valve yourself, but you need to replace it right away to ensure safety. Here are some tips to replace a pressure relief valve on an electric hot water heater.   

Prepare to Replace the Valve

For this project, you need:

  • work gloves
  • rags
  • bucket
  • garden hose
  • plumber's wrench or slip-joint pliers
  • plumber's tape
  • pipe fittings
  • replacement valve

Place a bucket under the valve to catch drips. Shut off electricity to the water heater from the breaker, and unplug it Turn off the water by turning the valve right. The shut off valve is commonly a knob located on the right of the cold line at the top of the water heater.

Set the temperature dial to the lowest setting. Open the hot water tap on a faucet release water pressure, in the lines, and leave it open. Attach a garden hose to drain valve on the tank bottom, drain about half of the tank in a floor drain, the tub, or outside.

Remove the Old Pressure Relief Valve

Disconnect the dip tube connected to the relief valve. If  the dip tube doesn't pull off or the pressure relief valve is connected to an exterior drain line, use a hacksaw to cut through it, being careful not to cut into the tank.Wipe the tube with a damp rag, and set it aside.  

Place the teeth of the wrench or slip joint pliers on the valve, and twist the wrench let to free the valve. Wipe old sealer or debris from the opening with a damp rag. Discard the old valve, or recycle it.   

Install the New Valve

Check to see if the faucet you opened is dripping. A slow drip is fine, but if it runs, ensure the water is completely turned off. 

Attach three or four layers of plumber's tape the to the connection threads of the new valve. Set the new valve in place, and give it three or four rotations with the wrench to tighten it. Attach the coupling to fix the ends of the dip tube, if you had to cut it, and reconnect the tube.

Turn the water and power back on to the hot water heater, and let air pressure release from the open faucet. Close the faucet. If you don't trust your skill. or the repairs keep failing, contact a plumber (such as one from Jim Dhamer Plumbing & Sewer, Inc.). Your hot water heater may be old, and needs replacing.