The thermostat and pressure release valve on a water heater was designed to help keep your family safe. Watch as one of our Master Plumbers shows you how to test your water heater's pressure valve and keep your home's hot water system functioning properly. In addition to testing the pressure release valve on your water heater, keep your thermostat set at a safe temperature, and flush your water heater annually. This will allow you to keep your system in good working condition and spot any minor problems before they become major issues.
Every water heater should be equipped with a temperature and pressure relief valve. This is a crucial safety device that is mandated by all plumbing codes and should never be removed or disabled. I'm Dave Jones, Master Plumber for Roto-Rooter Plumbing & Drain Service. I'm gonna discuss problems that sometimes occur with the temperature and pressure relief valves on the water heaters. Relief valves discharge for usually two reasons: 1, there's excessive pressure building up inside the system that is exceeding 150 pounds of pressure. Or 2, the temperature inside the tank is exceeding 210 degrees Fahrenheit. Both of these situations can be very dangerous and the temperature and pressure relief valve will open to prevent an explosion. If you notice water on the floor around the water heater and there's no evidence of a tank or plumbing leak, it is probably a sign that the water heater's temperature and pressure relief valve has recently opened and relieved itself. First you should test the water pressure in the house by using a pressure gauge that you will screw right onto a hose bib or a faucet. You could pick up one of these gauges at any home center. Most plumbing codes state that the maximum water pressure coming in the house should be 80 PSI or less. If the water pressure exceeds this amount, a pressure reducing valve will need to be installed on the water main. Note that the ideal water pressure is between 50 and 60 PSI. You want to make sure that the thermostat is not set too high. If the thermostat is set to high or if it's faulty, the T&P valve will discharge to relieve the pressure inside the tank. Remember for a standard water heater the temperature should be set at 120 degrees Fahrenheit. You could try flushing the T&P valve to make sure it didn't become filled by sediment. It's a good idea to test the T&P valve at least once a year to make sure its operating properly. Simply place a bucket beneath the discharge tube. You'll want to flip open the relief valve and let it run for about five seconds to make sure it opens fully. Stand back and don't do this if you're barefoot or wearing a open-toed shoes or sandals. If that hot water splashes out, you could be burned. Remember the T&P valve is the only thing that prevent your water heater from becoming a bomb. Once the valve snaps back, make sure it doesn't leak. If it does, you'll need to replace the valve. Next, check to make sure the expansion tank above the water heater hasn't failed. You can do this by removing the cap. It's located on top of the tank, and press in the Schrader valve. This is the same type of air valve that you'll find on tires. To see if air or water comes out of it. If water is expelled from the valve, then the tank needs to be replaced. I hope this is helpful and you have a better understanding of the temperature and pressure relief valve on your water heater. I'm Dave Jones, Master Plumber with Roto-Rooter. Thanks for watching. [Roto-Rooter jingle]