Справочник Пользователя для American Water Heater 319407-002

14

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 18). 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.

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.

1.   Locate the temperature and pressure relief valve on 

the water heater (also known as a T&P relief valve).  

See Figure 18.

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 19.  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 19).  Ensure 

that a discharge pipe is installed into the T&P valve 

discharge opening per the instructions in this manual.

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, electrical tape, or 

equivalent.   

7.   Repeat steps 5 and 6 for the hot water (outlet) pipe.

8.   Add additional sections of pipe insulation as needed.

Figure 18

Temperature and Pressure

Relief Valve Installation

Discharge Pipe

(Do not cap or plug.)

6" Maximum

Air Gap

Metal Drain Pan

Temperature and

Pressure Relief Valve

Floor

Drain

Drain Line

3/4” ID minimum

Figure 19 

 

T&P Relief Valve Insulation 

T&P Relief Valve

T&P Relief Valve 

Drain Line

Manual Relief Lever

T&P Relief Valve Insulation