Water Heater Relief Valve

A water heater has a valve on it that is meant to release water if the pressure or temperature in a water heater gets to high. The valve is found on either the side or the top of the water heater. In very rare case if the valve isn’t working and for some reason the pressure becomes extreme the water heater could potentially become like a bomb. Below you’ll find a picture of a 5 Gallon electric water heater that was located in a storage room adjacent to a school cafeteria.

Explosion caused by faulty relief valve

This occurence is rare and many different factors have had to occur for it to come to this but as you can see the results could be catastrophic. Fortunately this happened early in the morning and nobody was injured.

To make sure that your water heater relief valve is working properly manufactures recommend that you periodically test the valve. To test your valve you simply have to lift the lever on the valve to see if water comes out. It should be noted that when a water heater is older and hasn’t been tested previously the relief valve may stick in the open position or seep after testing. Just be sure you know how to shut the water off before testing. If this occurs the valve needs to be replaced.

It is also common for water heater relief valves to fail without even touching them. There doesn’t seem to be a good explanation why this occurs. So how do you know if your relief valve has failed or if there is a more serious problem with the heater itself and the valve is doing exactly what it’s supposed to do?

There are a few signs that can occur that let you know that there may be a problem. If you have any of these symptoms occurring in your home turn off the water and gas to the heater and call a professional immediately to have your heater replaced.

1) If the water in your home seems to be extremely hot compared to what it used to be and you’ve done nothing with the controls on the heater.

2) If you have hot water coming out of the cold tap of any faucet in your house.

3) If you have hot water in your toilet.

4) If the water heater relief valve is leaking and the water coming out of it is super heated steamy water.

There have been occasions when the water temperature has become so hot that when a person opens their tap only stem comes out. That is a clear indication that somethings wrong.

So what do you do if you have none of these symptoms and the valve has simply failed? Replacing a valve is a relatively easy job for most people to do. Just follow these steps:

1) Shut the water off and turn the heat down on the heater.

2) Open up the hot side of a faucet in the house. This allows the vacuum that is present in the water lines to be broken when attempting to drain the heater.

3) Hook up a garden hose to the drain valve located at the bottom of the heater and run it to your floor drain. For more info on how to drain a heater see this blog: How to Drain a Water Heater

4) Open up the drain valve and drain the heater down to a point where the water is below the relief valve. Note: you do not have to drain the heater all the way down.

5) Using a pipe wrench remove copper pipe that is attached to the relief valve. Make SURE you save this piece you will use it again.

6) Remove the old relief valve from the heater and go to your local hardware store with the valve to match it up to a new one. Not all relief valves are the same.

7) Prepare your new valve with teflon tape (make sure to put the tape on in the same direction that the valve screws in so that it doesn’t unravel as you screw it in).

8) Screw in the new valve tightly making sure to have the valve facing the correct direction.

9) Teflon tape the copper drop tube and screw it back into place.

10) Turn your water back on, turn the heat back up to where you had it, and turn off the faucet that you had opened earlier.

For more info or for any additional questions call us at 763-551-8990

Stop in and see us at 12700 Bass Lake Road Maple Grove, Mn 55369

Visit us on the web at levahnbros.com