Bradford White M-I-MS40T6LX Instruction Manual page 13

Water connections continued-
If this water heater is installed in a closed water supply system, such as the one having a
back-flow preventer in the cold water supply, provisions shall be made to control thermal
expansion. DO NOT operate this water heater in a closed system without provisions for
controlling thermal expansion. Your water supplier or local plumbing inspector should be
contacted on how to control this situation.
After installation of the water lines, open the main water supply valve and fill the water
heater. While the water heater is filling, open several hot water faucets to allow air to
escape from the water system. When a steady stream of water flows through the
faucets, close them and check all water connections for possible leaks. NEVER
OPERATE THE WATER HEATER WITHOUT FIRST BEING CERTAIN IT IS FILLED
WITH WATER.
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, ANSI 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 shall 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 shall 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.
WARNING
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