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If replaced, the new valve must meet the requirements of local codes,
but not less than a combination temperature and pressure relief
valve rated/sized and certified as indicated in the above paragraph.
The new valve must be marked with a maximum set pressure not to
exceed the marked hydrostatic working pressure of the water heater
(150 psi = 1,035 kPa) and a discharge capacity not less than the
water heater Btu/hr or KW input rate as shown on the water heater's
model rating plate.
For safe operation of the water heater, the temperature and pressure
relief valve must not be removed from its designated opening nor
plugged. The temperature-pressure relief valve must be installed
directly into the fitting of the water heater designed for the relief valve.
Install discharge piping so that any discharge will exit only within 6
inches (15.2 cm) above, or at any distance below the structural floor.
Be certain that no contact is made with any live electrical part. The
discharge opening must not be blocked or reduced in size under
any circumstances. Excessive length, over 30 feet (9.14 m), or
use of more than four elbows can cause restriction and reduce the
discharge capacity of the valve.
No valve or other obstruction is to be placed between the relief valve
and the tank. Do not connect discharge piping directly to the drain
unless a 6" (15.2 cm) air gap is provided. To prevent bodily injury,
hazard to life, or property damage, the relief valve must be allowed
to discharge water in adequate quantities should circumstances
demand. If the discharge pipe is not connected to a drain or other
suitable means, the water flow may cause property damage.
Property Damage Hazard
● The temperature-pressure relief-valve discharge pipe
must terminate at an adequate drain.
The Discharge Pipe:
•
Shall not be smaller in size than the outlet pipe size of the
valve, or have any reducing couplings or other restrictions.
•
Shall not be plugged or blocked.
•
Shall be of material listed for hot water distribution.
•
Shall be installed so as to allow complete drainage of both the
temperature-pressure relief valve and the discharge pipe.
•
Must terminate a maximum of six inches above a floor drain
or external to the building. In cold climates, it is recommended
that the discharge pipe be terminated at an adequate drain
inside the building.
•
Shall not have any valve or other obstruction between the
relief valve and the drain.
Water temperature over 125°F (52°C)
can cause severe burns instantly
resulting in severe injury or death.
Children, the elderly and the
physically or mentally disabled are at
highest risk for scald injury.
Feel water before bathing or shower-
ing.
Temperature limiting devices such as
thermostatic point-of-use mixing
valves must be installed when
required by codes and to ensure safe
temperatures at fixtures.
The temperature-pressure relief valve must be manually operated
at least once a year. Caution should be taken to ensure that (1) no
one is in front of or around the outlet of the temperature-pressure
relief valve discharge line, and (2) the water manually discharged
can cause bodily injury or property damage because the water may
be extremely hot. If after manually operating the valve, it fails to
completely reset and continues to release water, immediately close
the cold water inlet to the water heater, follow the draining instructions
in this manual, and replace the temperature-pressure relief valve
with a properly rated/sized new one.
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 back cover (page 24) of this manual for
technical assistance.
CLOSED WATER SYSTEMS
Water supply systems may, because of code requirements or such
conditions as high line pressure, among others, have installed
devices such as pressure reducing valves, check valves, and back
flow preventers. Devices such as these cause the water system to
be a closed system.
THERMAL EXPANSION
As water is heated, it expands (thermal expansion). In a closed
system the volume of water will grow when it is heated. As the
volume of water grows there will be a corresponding increase in
water pressure due to thermal expansion. Thermal expansion can
cause premature tank failure (leakage). This type of failure is not
covered under the limited warranty. Thermal expansion can also
cause intermittent temperature-pressure relief valve operation:
water discharged from the valve due to excessive pressure build
up. This condition is not covered under the limited warranty. The
temperature-pressure relief valve is not intended for the constant
relief of thermal expansion.
A properly sized thermal expansion tank should be installed on all
closed systems to control the harmful effects of thermal expansion.
Contact a local plumbing service agency to have a thermal expansion
tank installed.
ELECTRICAL
Electrical Shock Hazard
● Before removing any access panels or
servicing the water heater, make sure
the the electrical supply to the water
heater is turned OFF.
● Failure to follow these instructions can
result in personal injury or death.
GENERAL
The installation must conform with these instructions and the local
code authority having jurisdiction and the requirements of the power
company. In the absence of local codes, the installation must comply
with the current editions of the National Electrical Code, NFPA 70 or the
Canadian Electrical Code CSA C22.1.
An electrical ground is required to reduce risk of electrical shock
or possible electrocution. The water heater should be connected
to a separate grounded branch circuit with over-current protection
13
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