Daikin WGZ030DA, Installation, Operation And Maintenance Manual

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www.DaikinApplied.com 17 IOM 1322 • WATER-COOLED SCROLL COMPRESSOR
Relief Valve Piping
The ANSI/ASHRAE Standard 15, Safety Standard for
Refrigeration Systems, specifies that pressure relief valves
on vessels containing Group 1 refrigerant (R-410A) “shall
discharge to the atmosphere at a location not less than 15 feet
(4.6 meters) above the adjoining ground level and not less than
20 feet (6.1 meters) from any window, ventilation opening or
exit in any building.” The piping must be provided with a rain
cap at the outside terminating point and with a drain at the
low point on the vent piping to prevent water buildup on the
atmospheric side of the relief valve. Also, a flexible pipe section
should be installed in the line to eliminate any piping stress on
the relief valve(s).
Relief valves are located in the following places depending on
unit configuration:
• Low side with brazed plate evaporator - on the suction
line
• Low side with shell and tube evaporator - on the suction
line
• High side on packaged unit - on the condenser shell
• High side on remote condenser - if required - not factory
provided
Table 6: Relief Valve Information
The size of the discharge pipe from the pressure relief valve
should not be less than the size of the pressure relief outlet
(5/8 in. flare). See Figure 9 for pipe size when combining low
side relief on compressor suction with the condenser relief
valve.
Figure 9: Relief Valve Piping
NOTE: Fittings should be provided to permit vent piping to be
easily disconnected for inspection or replacement of
the relief valve.
Refrigerant Piping