American Water Heater 318935-003 Temperature and Pressure Relief Valve, Explosion Hazard

Models: 318935-003

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Temperature and Pressure Relief Valve

Temperature and Pressure Relief Valve

The Temperature & Pressure Relief Valve:WARNING

Explosion Hazard

If the temperature and pressure relief valve is dripping or leaking, have a qualified person replace it.

Examples of a qualified person include: licensed plumbers, authorized gas company personnel, and authorized service personnel.

Do not plug valve. Do not remove valve.

Failure to follow these instructions can result in death, or explosion.

Figure 15A

Temperature and Pressure

Relief Valve Installation

Optional location

some models only

Temperature and

Pressure Relief Valve

Discharge Pipe

(Do not cap or plug.)

Drain Line

3/4” ID minimum

6" Maximum

Air Gap

Floor The Discharge Line:

Drain

Metal Drain Pan

For protection against excessive pressures and temperatures, a temperature and pressure relief valve must be installed in the opening marked “T & P RELIEF VALVE” (see Figure 15A). This valve must be design certified by

a nationally recognized testing laboratory that maintains periodic inspection of the production of listed equipment or materials as meeting the requirements for Relief Valves and Automatic Shut-off Devices for Hot Water Supply Systems, ANSI Z21.22. The function of the temperature and pressure relief valve is to discharge water in large quantities in the event of excessive temperature or pressure developing

in the water heater. The valve’s relief pressure must not exceed the working pressure of the water heater as stated on the data plate.

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IMPORTANT: Only a new temperature and pressure relief valve should be used with your water heater. Do not use an old or existing valve as it may be damaged or not adequate for the working pressure of the new water heater. Do not place any valve between the relief valve and the tank.

The Temperature & Pressure Relief Valve:

Must not be in contact with any electrical part.

Must be connected to an adequate discharge line.

Must not be rated higher than the working pressure shown on the data plate of the water heater.

The Discharge Line:

Must not be smaller than the pipe size of the relief valve or have any reducing coupling installed in the discharge line.

Must not be capped, blocked, plugged or contain any valve between the relief valve and the end of the dis- charge line.

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.

Must be capable of withstanding 250°F (121°C) without distortion.

Must be installed to allow complete drainage of both the valve and discharge line.

T&P Relief Valve and Pipe Insulation (Some Models)

1.Locate the temperature and pressure relief valve on the water heater (also known as a T&P relief valve). See Figure 15B.

2.Locate the slit running the length of the T&P relief valve insulation.

3.Spread the slit open and fit the insulation over the T&P relief valve. See Figure 15B. 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 15B).

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 flush 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.

Figure 15B

T&P Relief Valve Insulation

T&P Relief Valve Insulation

Manual Relief Lever

T&P Relief Valve

T&P Relief Valve

Drain Line

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American Water Heater 318935-003 Temperature and Pressure Relief Valve, T&P Relief Valve and Pipe Insulation Some Models