Hussmann Ingersoll Rand, User Manual

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Installation and Start-up 7
Leak Testing
Evaluate the refrigeration circuit assembly according to ANSI/ ASHRAE 15 or valid
equivalent safety standards. The following procedure is recommended for leak checking
the refrigeration system prior to starting any compressor.
1. Visually inspect all lines and joints for proper piping practices.
2. Isolate the following components.
a. Compressors – front seat suction and discharge service valves, and
close all oil supply and equalization lines.
b. Pressure transducers.
c. Other components such as, piloted control valves, as recommended by
the manufacturer.
3. Open all other refrigerant line ball valves and solenoid valves.
Test Charge
4. Use properly regulated dry nitrogen and a refrigerant to pressurize the system
with vapor only. (Note: regardless of which refrigerant is used for the
operating charge, R22 may be used for leak checking and pressure testing
prior to start-up.) Charge a small amount of refrigerant through a dehydrator,
and add dry nitrogen through a separate line to bring the system pressure up to
150 psig. Use an electronic leak detector to inspect all connections.
5. If a leak is found isolate, repair and retest.
Danger! Never trap liquid refrigerant between closed valves, especially when
applying heat to repair a leak. Hydraulic explosion may result.
6. After repairing all leaks, assure all valves are re-opened and the system charge
is maintained at 150 psig.
7. Using a vacuum pump, evacuate the system to approximately 1-5 psia.
8. The system should stand unaltered for approximately 12 hours with no
increase in pressure.