Could be just a weak relief valve, but you need to check for thermal expansion as well, especially if there is a pressure reducer, check valve or backflow preventor on the main water line into the house. If you have thermal expansion the pressure could easily get up to 150 PSI and make the relief valve discharge. After replacing the existing relief valve put a pressure gauge on a hose faucet or laundry tub spout or water heater drain. With no other water running and your water heaters power shut off, check your static pressure–should be about 40-75 PSI. Watch it for a few minutes to make sure it doesnt creep up. Now fire up the water heater (make sure it is actually running) and watch the gauge–if there is thermal expansion you will see the pressure go up. If there is thermal expansion you will need to install a thermal expansion tank on the cold water line to the water heater to absorb the pressure increase.: My pressure regulator valve is leaking and seems to be getting worse. If I tap on it lightly, the leaking will stop but will always return. Is this a faulty valve or are there internal problems that require other corrective actions?: Thanx in advance! : Jim : go8b@aol.com
