American Water Heater ADCG, DCG3-Series Temperature & Pressure Relief Valve, Discharge Line

Index

Temperature and Pressure			must not exceed the working pressure of the water
Relief Valve			heater as stated on the data plate.
			Important: Only a new temperature and pressure relief
			valve should be used with this 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 or piping 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
		Explosion Hazard
			heater.
	If the temperature and pressure relief
			• The BTUH rating of the T & P valve must be
	valve is dripping or leaking, have a		greater than, or equal to, the input rating of the
	qualified service technician replace it.		water heater.
	• Do not plug valve.		The Discharge Line:
	• Do not remove valve.		• Must not be smaller than the pipe size of the
			relief valve or have any reducing coupling
	Failure to follow these instructions can
			installed in the discharge line.
	result in death or explosion.		• Must not be capped, blocked, plugged or
			contain any valve between the relief valve and
			the end of the discharge line.
	Figure 9: T&P Relief Valve
			• Must terminate a maximum of 6 inches (152mm)
			above a floor drain or external to 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.

Index

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 9). 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. (CSA4.4, Temperature, Pressure, Temperature and Pressure Relief Valves and Vacuum Relief Valves in Canada). The function of the temperature and pressure relief valve is to discharge water in large quantities in the event of excessive temperature or pressure devel- oping in the water heater. The valve's relief pressure

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