Rheem AP15121-1 - Manual (Page 7)

! WARNING: The pressure
rating of the relief valve must
not exceed 150 PSI, the
maximum working pressure of
the water heater as marked on
the rating plate.
A new combination temperature and pressure relief valve, complying with the Standard for Relief Valves and
Automatic Gas Shut-Off Devices for Hot Water Supply Systems, ANSI Z21.22/CSA 4.4, is installed in the
opening provided. No valve of any type should be installed between the relief valve and the tank. Local codes
shall govern the installation of relief valves.
Relief Valve
The BTUH rating of the relief valve
must not be less than the input rating
of the water heater as indicated on the
rating label located on the front of the
heater (1 watt=3.412 BTUH).
Connect the outlet of the relief valve
to a suitable open drain so that the
discharge water cannot contact live
electrical parts or persons and to
eliminate potential water damage.
Piping used should be of a type
approved for hot water distribution.
The discharge line must be no smaller
than the outlet of the valve and must
pitch downward from the valve to
allow complete drainage (by gravity)
of the relief valve and discharge line.
The end of the discharge line should
not be threaded or concealed and
should be protected from freezing.
No valve of any type, restriction or
reducer coupling should be installed in
the discharge line.
7
Typical Installation
Electrical Access for
Hook-up
Hot water outlet to fixtures
Cold Water Supply
Drain Valve
Temperature and Pressure Relief
Valve and discharge line
Union
Union
Heat Pump Filter
Access Door to
Temperature Control
Shut Off Valve
6" Air Gap
Thermal Expansion
Tank (if required)
8" Minimum Clearance above Heat
Pump to allow air circulation
Ceiling in Alcove
Primary Condensate line (3/4")
to open drain or outdoors
Heat Trap
6" Min.
Secondary Condensate tubing
(1/2") to open drain or outdoors