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Secure all insulation using tape.
FIGURE 25.
WATER PIPING PRESSURE TEST
•
If water piping system is to be air pressure tested, the water
heater must be disconnected from the water piping system.
•
Failure to disconnect the water heater during air pressure
testing of the water system could result in DEATH, SERIOUS
BODILY INJURY, OR PROPERTY DAMAGE.
This section is only for the manufacturer installing the water heater
when the installation is to comply with H.U.D. Standards.
When testing the water ways, H.U.D. Standards state:
"Water distribution system. All water piping in the water distribution
system shall be subjected to a pressure test. The test shall be made by
subjecting the system to air or water at 100 psi for 15 minutes without
loss of pressure. When air pressure is used, the water heater
shall not be connected during the test".
NOTE: If water piping system is to be air pressure tested, the water
heater must be disconnected from the water piping system. Failure to
disconnect the water heater during air pressure testing of water piping
system could result IN DEATH, SERIOUS BODILY INJURY, OR
PROPERTY DAMAGE.
FIGURE 26.
TEMPERATURE-PRESSURE RELIEF VALVE
This heater is provided with a properly certified combination
temperature - pressure relief valve by the manufacturer.
The valve is certified by a nationally recognized testing laboratory that
maintains periodic inspection of production of listed equipment of
materials as meeting the requirements for Relief Valves and Automatic
Gas Shut-off Devices for Hot Water Supply Systems, ANSI Z21.22 •
CSA 4.4, and the code requirements of ASME.
If replaced, the valve must meet the requirements of local codes, but
not less than a combination temperature and pressure relief valve
certified as indicated in the above paragraph.
The valve must be marked with a maximum set pressure not to exceed
the marked hydrostatic working pressure of the water heater
(150 psi = 1,035 kPa) and a discharge capacity not less than the water
heater input rate as shown on the model rating plate.
For safe operation of the water heater, the relief valve must not be
removed from its designated opening nor plugged.
The temperature-pressure relief valve must be installed directly into
the fitting of the water heater designed for the relief valve. Position the
valve downward and provide tubing so that any discharge will exit
only at any distance below the structural floor. Be certain that no
contact is made with any live electrical part. The discharge opening
must not be blocked or reduced in size under any circumstances.
Excessive length, over 30 feet (9.14 m), or use of more than four
elbows can cause restriction and reduce the discharge capacity of
the valve, see Figure 27.
No valve or other obstruction is to be placed between the relief valve
and the tank. Do not connect tubing directly to discharge drain unless
a 6 inch air gap is provided. To prevent bodily injury, hazard to life, or
property damage, the relief valve must be allowed to discharge water
in quantities should circumstances demand. If the discharge pipe is not
connected to a drain or other suitable means, the water flow may
cause property damage.
The Discharge Pipe:
• Shall not be smaller in size than the outlet pipe size of the valve, or
have any reducing couplings or other restrictions.
15
• Temperature-pressure relief valve
must comply with ANSI Z21.22
and ASME code.
• Properly sized temperature-relief
valve must be installed in opening
provided.
• Can result in overheating and
excessive tank pressure.
• Can cause serious injury or death.
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