Steve
: Getting a discharge from the pressure releif valveT&P s (Temp & Pressure) are set for 210 degrees, boiling, and 150 PSI. First thing I check is the water pressure. If pressure is more than 80 pounds, than a PRV should be installed. A system with a check valve on it will allow the hot water to expand and build pressure. If a check valve is causing excessive pressure buildup a expansion tank should be installed. If pressure is below 80 pounds, replace the T&P
