Water Connections; Pressure Relief Valve - A.O. Smith 910 Installation Manual And Owner's Manual

Do not use this appliance if any part has been under water. Immediately contact a
qualified installer or service agency to replace a flooded water heater. Do not attempt
to repair the unit! It must be replaced! Failure to follow these instructions could lead to
WARNING
property damage, personal injury, or loss of life.
Do not reverse the hot outlet and cold inlet connections to the water heater. This will
NOTICE
prevent the water heater from activating properly.
All pipes, pipe fittings, valves and other components, including soldering materials, must be suitable for
potable water systems.
1. A manual shutoff valve must be installed on the cold water inlet to the water heater between the
main water supply line and the water heater.
2. In addition, a manual shutoff valve is recommended on
the hot water outlet of the unit. Isolation valves are
recommended.
3. If the water heater is installed within, or subjected
to, a closed loop water system, a thermal expansion
tank or a code approved device to handle thermal
expansion must be installed.
4. Before installing the water heater, flush the water
line to remove all debris, and after installation is
complete, purge the air from the line. Failure to
do so may cause damage to the water heater.
5. There is a wire mesh filter within the cold inlet
to trap debris from entering your heater. This
will need to be cleaned periodically to maintain
optimum flow. (Refer to p. 40.)
The water heater has a high-temperature shutoff switch built in as a standard safety feature (called a
Hi-Limit switch). Therefore, a "pressure only" relief valve is required.
This unit does not come with an approved pressure relief valve.
An approved pressure relief valve must be installed on the hot water outlet.
The pressure relief valve must conform to the current edition of ANSI Z21.22 or CAN 1-4.4 and installation must
follow local codes.
The discharge capacity must be at least 380,000 BTU/h.
The pressure relief valve must be rated for a maximum of 150 psi (1 MPa).
The discharge piping for the pressure relief valve must be directed so that the hot water cannot splash outward
and cause damage or personal injury.
Attach the discharge tube to the pressure relief valve and run the end of the tube to within 6 in. (152 mm) from
the floor. This discharge tube must allow free and complete drainage without any restrictions.
If the pressure relief valve installed on the water heater discharges periodically, this may be due to a defective
thermal expansion tank or defective pressure relief valve.
The pressure relief valve must be manually operated periodically to check for correct operation.
No valve shall be placed between the relief valve and the water heater.
For the ASME model, the pressure relief valve must conform to and be installed in accordance with ASME code.
Hot water could be released when the pressure relief valve is opened. This
could result in severe personal injury. Contact with discharge may cause prop-
erty damage and/or bodily harm. Before operating the pressure relief valve
manually, check that it will discharge in a safe place. If water does not flow
WARNING
freely from the end of the discharge pipe, turn the gas supply and power OFF
and call a qualified person to determine the cause.
Refer to the pressure relief valve manufacturer's instructions for inspection and
maintenance requirements.
As Close as
Possible

-Pressure relief valve-

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