47
Figure 45. Testing the Temperature-Pressure Relief Valve
If the Temperature-Pressure Relief Valve on the water heater weeps
or discharges periodically, this may be due to thermal expansion.
Note:
Excessive water pressure is the most common cause of
Temperature-Pressure Relief Valve leakage. Excessive
water system pressure is most often caused by “thermal
expansion” in a “closed system.” See
Closed Water Systems
and
Thermal Expansion
(page 30). The Temperature-Pressure
Relief Valve is not intended for the constant relief of thermal
expansion.
Temperature-Pressure Relief Valve leakage due to pressure build
up in a closed system that does not have a thermal expansion
tank installed is not covered under the limited warranty. Thermal
expansion tanks must be installed on all closed water systems.
DO NOT PLUG THE TEMPERATURE-PRESSURE RELIEF
VALVE OPENING. THIS CAN CAUSE PROPERTY DAMAGE,
SERIOUS INJURY OR DEATH.
If you do not understand these instructions or have any questions
regarding the Temperature-Pressure Relief Valve call the toll
free number listed on the front page of this manual for technical
assistance.
•
Temperature-pressure relief valve
must comply with ANSI
Z21.22-CSA4.4 and ASME code.
•
Properly sized temperature-pressure
relief valve must be installed in
opening provided.
•
Do not plug, block, or cap the
discharge line.
•
Failure to follow this warning can
result in excessive tank pressure,
serious injury or
death.
Explosion Hazard
WARNING
SERVICE
If a condition persists or you are uncertain about the operation of the
water heater contact a qualified service technician.
Use this guide to check a leaking water heater. Many suspected
Leakers are not leaking tanks. Often the source of the water can be
found and corrected.
If you are not thoroughly familiar with gas codes, your water heater,
and safety practices, contact your gas supplier or qualified installer
to check the water heater.
Read this manual first. Then before checking the water heater make
sure the gas supply has been turned “OFF”, and never turn the gas
“ON” before the tank is completely full of water.