Water Heaters - T & P Gone Bad?

Have a 7 year old LP gas fired 50 gallon tall water heater. Last night, had no hot water. Upon inspecting water heater, discovered that the T & P valve had released some water and the pilot light was off. Heat thermostat set for 140 degrees. Relighted the pilot and the burner fired normally. The T & P valve was leaking at a steady drip, drip, drip. Is the result I observed (e.g., T & P valve releasing water, pilot light off, T & P leaking) an indication of a bad T & P valve or a bad thermostat that allowed the water to overheat? After I relighted the pilot, the water temp warmed to 140 degrees and the burner shut down. T & P still has dripping leak. Thanks.

Hi KansasJohn,
Welcome to the DIY Forums.

While the T&P valve may be a problem, I believe the 140° temp you have the heater set at is more of a problem. Most T&P valves are pre-set to trip at 150°. Try turning the water temp down to 120° and see if that helps the problem. If it does not help, I would then change the T&P valve. You MIGHT be able to find a T&P valve pre-set at a higher temp but highly unlikely. These valves are pre-set to minimize the explosion hazard of overly heated water in a confined space(heater tank).
Good luck with your project.