User Guide

TECHNICAL SERVICE DEPARTMENT
Technical Service Bulletin
1-800-432-8373
Temperature And Pressure Relief Valves
Discharge of the T&P valve may indicate that an unsafe temperature or pressure condition exists.
Contact a licensed plumber immediately!
Technical Competence, Product Confidence
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T&P valves should be inspected and tested on every service call. When checking the
valve, also check the rating plate on the valve. Many changes may take place in a plumbing
system after the original installation. Through a systemic reinspection program, we can insure
that the safety device is working properly. The T&P Valve must be capable of discharging more
BTUs than the heater is capable of putting into the water.
Installation of a temperature and pressure relief valve is critical to the safe operation of a
water heater. The basic rule is that the T&P valve must be installed so that the temperature-
sensing probe is immersed in the hottest water in the top six inches of the tank. All water heaters
manufactured by Rheem – Ruud have a separate and special connection designed for the T&P
valve.
T&P Location
Residential Electric
T&P Location
Commercial Gas
Here are some common T&P valve errors:
No T&P installed or pressure only relief valve
installed
Non-code or insufficient rating T&P valve
installed
T&P installed in the cold water line
T&P installed a distance from the tank, such
as in the hot outlet line
T&P has been altered or repaired
T&P valve drain line is plugged or restricted
Tips for the Temperature and Pressure
Relief drain line:
Run to a safe place of disposal (floor drain or
outside)
Drain piping should be the same size as the
valve discharge through its entire length
Pitch downward from the valve
Terminate 6 inches above the floor drain
No longer than 30 feet
Not use more than four elbows
Do not install a shut off valve in the drain line
Terminate unthreaded