Specifications

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2.6 Leak Testing
No installation is complete until the entire system has been thoroughly checked for leaks.
This includes checking refrigerant tubing, fl are fi ttings, pressure controls, Shrader fi ttings
and compressor rota-lock service valves.
In addition to the refrigeration system, check all condenser water lines, humidifi er makeup lines,
condensate lines, condensate pumps, chilled water lines, centrifugal pumps, and fl uid coolers as
applicable.
With recent changes in the handling and recovery of refrigerant, it is not permissible to release
refrigerant into the atmosphere. Many leak-test methods recommended in the past are no longer
possible. Current standard practices must be used.
Pressurize system circuit to 150 PSIG (1034kPa) by using dry nitrogen with a trace of refrigerant.
Check the entire system for leaks with suitable leak fi nder, (per local code) including but not limited
to all braze joints, caps, fi ttings and fl are nuts on both fi eld and factory furnished components. After
completion of leak testing, release test pressure and pull a vacuum on the system.
Tightening of fi ttings and valves is the responsibility of the installing contractor.
2.7 Evacuation
Evacuate the refrigerant lines, condenser coil and evaporator coil to 250 microns or lower (a
micron gauge and 2-stage vacuum pump are required). Valve off and turn off the vacuum pump
and wait for at least 15 minutes to make sure the micron gauge reading does not go back above 700
microns. If it does, restart the vacuum pump and evacuate until the system reaches 250 microns.
If the system still does not hold the pressure below 700 microns the system needs to be rechecked
for leaks.
After the system has been satisfactorily evacuated the lines can be charged with refrigerant.
Connect the pressure gauge manifold set to the high and low ports near the compressor. Connect
the charging line to the refrigerant tank and set it for liquid feed. Open the refrigerant tank valve
and purge the line at the manifold, then open the high side valve on the manifold only and allow the
refrigerant fl ow until the system pressure equalizes. At this point the system will have 75 to 80% of
the total refrigerant charge. Start the blower(s) and then the compressors checking the operating
pressures and temperatures.
NOT APPLY POWER TO THE COMPRESSOR WHEN IN A VACUUM