A Temperature Pressure Relief (TPR) valve is a critical safety device that automatically releases water when tank temperature exceeds 210°F or internal pressure exceeds 150 PSI, preventing tank rupture. Federal law requires TPR valves on all water heaters as primary safety protection against catastrophic failure.
Technical Specifications
TPR valves must be installed within 6 inches of the water heater’s hottest point, typically on the side near the top of the tank. They feature a temperature-sensitive element that opens at 210°F and a pressure-sensitive component set at 150 PSI. Discharge lines must extend downward to within 6 inches of the floor to safely direct expelled water away from living areas.
Maintenance and Testing
TPR valves should be tested annually by lifting the lever handle briefly to confirm water discharge. A stuck or inoperative valve requires immediate replacement, typically a 15-minute job costing $150-250 including the valve and discharge piping modifications.
Safety Significance
A failed TPR valve leaves the tank vulnerable to pressure and temperature buildup, risking explosion-like tank failure that can cause severe injury and property damage. Regular testing and prompt replacement maintain critical safety protection for household occupants.