A water heater is an appliance that that mostly runs unnoticed until there is a problem. That is why it is worth testing the water heater from time to time to determine if the tank needs to be repaired or replaced. Here are is what you should know about testing the pressure and temperature relief valve on the tank.
Why Test the Relief Valve?
Your hot water tank has a valve for both pressure relief and temperature that is essentially a safety device. This valve will open and release hot water when the pressure or water temperature inside the tank is above the acceptable range for safety. If you want to get into the nitty-gritty details of it, it prevents water from getting hotter than 210°F, and the pressure inside from exceeding 150 psi. Having either of these factors be too high within the tank, and the water heater is put under a lot of unnecessary stress. In extreme situations, the tank can burst due to the pressure inside it.
That is why it is worth testing this valve periodically. You can identify the valve since it is at the top part of the tank and has a section of PVC pipe attached to it that goes down to the floor. The reason for the long PVC pipe is to prevent you from being splashed accidentally by hot water when testing the valve.
How Can You Test the Relief Valve?
Testing the valve is very simple to do. It is best to shut down the water heater before testing it, which will prevent the water coming out of the valve to be scalding hot. Just let the tank remain off for about an hour, and it should be fine.
Next, place a bucket underneath the PVC pipe going toward the floor, which will collect any water that comes out. The valve itself should have a metal lever located on it that can be moved to open up the valve. You want this lever to point straight up. It should generate a burst of air that is exiting through the PVC pipe.
After several seconds, water will start coming out from the pipe. Be concerned if the water is only trickling out instead of exiting in a constant stream. Once you are done testing the valve, flip the valve's lever back down and contact a company like Quality Plumbing to service your tank if necessary. They will let you know if repair or replacement of the tank is in your future.