Temperature-Pressure Relief Valve - A.O. Smith GPD-40 Instruction Manual

solder the cold water supply line directly to the cold water inlet.
It will harm the dip tube and damage the tank.
T & P Valve and Pipe Insulation (if supplied)
1. Locate the temperature and pressure relief valve on the water
heater (also known as a T&P relief valve). See Figure 11.
2. Locate the slit running the length of the T&P relief valve
insulation.
3. Spread the slit open and fi t the insulation over the T&P relief
valve. See Figure 11. Apply gentle pressure to the insulation to
ensure that it is fully seated on the T&P relief valve. Once seated,
secure the insulation with duct tape, electrical tape, or equivalent.
IMPORTANT: The insulation or tape should not block or cover the
T&P relief valve drain opening. Also, the insulation or tape should
not block or hinder access to the manual relief lever (Figure 11).
4. Locate the hot water (outlet) & cold water (inlet) pipes to the water
heater.
5. Locate the slit running the length of a section of pipe insulation.
6. Spread the slit open and slip the insulation over the cold water
(inlet) pipe. Apply gentle pressure along the length of the insulation
to ensure that it is fully seated around the pipe. Also, ensure that
the base of the insulation is fl ush with the water heater. Once
seated, secure the insulation with duct tape.
7. Repeat steps 5 and 6 for the hot water (outlet) pipe.
8. Add additional sections of pipe insulation as needed.
T&P RELIEF VALVE INSULATION
MANUAL RELIEF LEVER
T&P RELIEF VALVE
T&P RELIEF VALVE
DRAIN LINE
FIGURE 11.

TEMPERATURE-PRESSURE RELIEF VALVE

.
This heater is provided with a properly certified combination
temperature - pressure relief valve by the manufacturer. The valve is
certifi ed by a nationally recognized testing laboratory that maintains
periodic inspection of production of listed equipment of materials as
meeting the requirements for Relief Valves for Hot Water Supply Systems,
ANSI Z21.22 • CSA 4.4, and the code requirements of ASME.
Explosion Hazard
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If replaced, the valve must meet the requirements of local codes, but
not less than a combination temperature and pressure relief valve
certifi ed as indicated in the above paragraph.
The 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 input rate as shown on the model rating plate.
For safe operation of the water heater, the relief valve must not be
removed from its designated opening nor plugged.
The temperature-pressure relief valve must be installed directly into
the fi tting of the water heater designed for the relief valve. Position
the valve downward and provide tubing so that any discharge will exit
only within 6 inches (15.2 cm) above an adequate drain or outside of
the building or structure. 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. See Figures 10 or 14.
No valve or other obstruction is to be placed between the relief valve
and the tank. Do not connect tubing directly to discharge 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 quantities should circumstances demand. If the discharge
pipe is not connected to a drain or other suitable means, the water
fl ow may cause property damage.
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.
• Shall terminate a maximum of six inches above a fl oor 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 between the relief valve and tank.
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
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