: about a gallon of water drips from the discharge pipe of my baseboard hot water furnace. This problem existed last year so I replaced the pressure relief valve and the leak stopped. Last week, it started again. I checked the air pressure on the expansion tank it reads 12 lbs. Seven years ago I replaced both the tank and the valve. The furnace is 25 years old. What do you suggest?
The 12 lb. reading from the Schrader valve on the expansion tank is not an accurate reading of the system pressure, check the boiler pressure gauge.
The feed and/or relief valve could be defective.
Good Luck & Happy New Year. e-plumber