A.O. Smith 318257-000 Temperature and Pressure Relief Valve, Temperature & Pressure Relief Valve

Temperature and 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 electric 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 5

Temperature and Pressure

Relief Valve Installation

Temperature and

Pressure Relief Valve

Discharge Pipe

(Do Not Plug or Cap)

Drain Pan 2 1/2” Depth Maximum and 2 Inches wider than the water heater.

Drain Line 3/4”	Drain	6” Maximum
ID Minimum		Air Gap

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 5).

To reduce the risk of excessive pressures and temperatures in this water heater, install temperature and pressure relief protective equipment required by local codes, but no less than a combination temperature and pressure relief valve 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 Shutoff Devices for Hot Water Supply Systems, ANSI Z21.22 - latest edition. This valve must be marked with the maximum set pressure not to exceed the marked maximum working pressure of the water heater. Install the valve into an opening provided and marked for this purpose in the water heater, and orient it or provide tubing so that any discharge from the valve exits only within 6 inches above drain, or at any distance below, the structural floor, and does not contact any live electrical part. The discharge opening must not be blocked or reduced in size under any circumstance.

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:

•Shall not be in contact with any electrical part.

•Shall be connected to an adequate discharge line.

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

The Discharge Line:

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

•Shall not be capped, blocked, plugged or contain any valve between the relief valve and the end of the discharge line.

•Shall 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 be of material listed for hot water distribution.

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

Temperature/Pressure Relief Valve and Pipe Insulation

1.Locate the temperature and pressure relief valve on the water heater (also known as a T&P relief valve). See Figure 5.

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 6. Apply gentle pressure to the insulation to ensure that it is fully seated on the T&P Re- lief Valve. Once seated, secure the insulation with duct tape, electrical tape, or equivalent.

IMPORTANT: The insulation and tape must not block the discharge opening or hinder access to the manual relief lever (Figure 6). Ensure a discharge pipe is in- stalled into the T&P valve discharge opening per the instructions in this manual.

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