Super Hot EPJ-119-SC, Installation And Service Manual

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EPJ SERIES INDIRECT WATER HEATERS – Installation and Service Manual
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3.5 T&P RELIEF VALVE
DANGER – Risk of Explosion: A T&P (temperature and pressure) relief valve certified by a nationally
recognized testing laboratory to the requirements of ANSI Z21.22/CSA 4.4 - Relief valves for hot water
supply systems must be installed to protect the tank from excessive temperature and pressure. The T&P
relief valve must have a rating greater than the gross input of the boiler connected to the indirect
water heater.
The T&P relief valve must have a maximum temperature setting of 150°F and maximum
pressure setting of 150 PSIG. Do not plug T&P relief valve or discharge piping. Plugging the T&P relief
valve or discharge piping can cause excessive pressure in water heater, resulting in severe personal injury,
death or substantial property damage.
WARNING: The T&P relief valve may discharge pressurized hot water and/or steam. Steam exiting the
discharge outlet can explosively expand in any direction. Always maintain a safe distance from the
discharge pipe outlet in order to avoid potential contact with exiting hot water or steam.
Temperature and pressure settings of a T&P relief valve are factory set and are not adjustable. The service
pressure should be at least 25 psi less than the setting stamped on the T&P relief valve.
Install the T&P relief valve directly into the T&P relief valve fitting, labeled “RELIEF VALVE”, so that the
temperature sensing element is immersed in water in the top of the tank. No valve, reducing coupling or
other restriction is to be placed between the T&P relief valve and the tank connection. No valve, reducing
coupling, pipe plug, pipe cap or other restriction is to be placed in the discharge piping. Improper placement
or piping of the T&P relief valve can cause severe personal injury, death or substantial property damage.
The discharge line must be installed to allow the complete drainage of both the valve and the line. It shall
be independently supported or arranged so as to avoid undue stress on the valve.
Do not pipe in any area
where freezing may occur.
The termination of the T&P relief valve discharge line shall be downward and not directly connected to a
sewer line. The outlet of the discharge line shall terminate in the vicinity of a point of drainage within 6” of
the floor to eliminate potential risk of scalding, and should terminate freely to atmosphere where any
discharge will be clearly visible and is at no risk of freezing.
3.6 WATER HAMMER
Water hammer is a damaging pressure shock wave created when the flow of water is suddenly stopped or
reduced (possibly induced by a fast-closing faucet, reducing valve, or solenoid valve in a clothes/dish
washing machine). This condition is commonly associated with hammering noises and vibrations; however,
lack of noise does not assure that water hammer is not present. Risers or air chambers do not provide
protection. To prevent damage to pipes and appliances: (1) install water hammer arrestors of adequate
size at all required locations and (2) adequately size pipes to ensure a maximum water velocity less than
5 ft/s.