Bradford White PDX1-40S6FBN Installation And Operating Instruction Manual page 38

Water Connections continued-
WARNING
For protection against excessive temperatures and pressure, install
temperature and pressure protective equipment required by local
codes, but not less than a combination temperature and pressure relief
valve certified by a nationally recognized testing laboratory that
maintains periodic inspection of production of listed equipment or
materials as meeting the requirements of the Standard for Relief Valves
and Automatic Gas Shutoff Devices for Hot Water Supply Systems,
ANS Z21.22 or the Standard CAN1-4.4. Temperature and Pressure and
the Standard CAN1-4.4, Temperature, Pressure, Temperature and
Pressure Relief Valves and Vacuum Relief Valves. The combination
temperature and pressure relief valve must be marked with a maximum
set pressure not to exceed the maximum working pressure of the water
heater. The combination temperature and pressure relief valve must
also have an hourly rated temperature steam BTU discharge capacity
not less than the hourly rating of the water heater.
Install the combination temperature and pressure relief valve into the
opening provided and marked for this purpose on the water heater.
Note: Some models may already be equipped or supplied with a
combination temperature and pressure relief valve. Verify that the
combination temperature and pressure relief valve complies with local
codes. If the combination temperature and pressure relief valve does
not comply with local codes, replace it with one that does. Follow the
installation instructions above on this page.
Install a discharge line so that water discharged from the combination
temperature and pressure relief valve will exit within six (6) inches (15.2
cm) above, or any distance below the structural floor and cannot
contact any live electrical part. The discharge line is to be installed to
allow for complete drainage of both the combination temperature and
pressure relief valve and the discharge line. The discharge opening
must not be subjected to blockage or freezing. DO NOT thread, plug or
cap the discharge line. It is recommended that a minimum clearance of
four (4) inches (10.2 cm) be provided on the side of the water heater for
servicing and maintenance of the combination temperature and
pressure relief valve.
Do not place a valve between the combination temperature and
pressure relief valve and the tank.
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