WARNING
Explosion Hazard!
Failure to properly regulate pressure could result in a
violent explosion, which could result in death, serious
injury, or equipment or property-only-damage.
When using dry nitrogen cylinders for pressurizing units
for leak testing, always provide a pressure regulator on
the cylinder to prevent excessively high unit pressures.
Never pressurize unit above the maximum
recommended unit test pressure as specified in
applicable unit literature.
Removal and Installation
18
COM-SVN01D-EN
Pressure Testing
•
Use industry-standard and EPA-accepted techniques
for testing.
•
Pressure tests must be performed by qualified
personnel.
•
Use tools especially designed for leak testing.
•
Do not exceed the high-side and low-side pressures
listed on the unit nameplate.
•
If no test pressure value is listed on the nameplate of
the unit, a pressure of no more than 150 psig is
acceptable.
•
The CSHN compressor has an internal check valve.
When pressurizing the system, it is important to never
allow the low side pressure to exceed the high side
pressure by more than 5 bar (72 psig). Greater
pressure differential could result in compressor
damage. Also slowly raise the pressure over a
2-minute time period to allow sufficient time for
internal pressures in the compressor to equalize.
NOTICE
Overpressure Damage!
Do not pressurize the low side of the compressor by
more than 5 bar (72 psig) higher than the high side of
the compressor within less than two minutes. Failure to
follow these instructions could result in compressor
damage.
•
Pressure decay testing can be used to check for gross
leaks but will not be able to detect the location of a leak.
•
After pressurizing the system use an R-410A leak
detection device to detect and locate leaks.
Vacuum Testing and Evacuation
•
Use the procedure as described in the unit Installation,
Operation, and Maintenance manual (see
•
If no other information is available, use the following
information.
NOTICE
Compressor Motor Damage!
Never use the compressor as a vacuum pump. Never
meg-ohm test or apply power to the compressor while
it is in a vacuum. Failure to follow these instructions
could cause compressor motor damage.
WARNING
Hazardous Voltage w/Capacitors!
Disconnect all electric power, including remote
disconnects and discharge all motor start/run
capacitors before servicing. Follow proper lockout/tag
out procedures to ensure the power cannot be
inadvertently energized. Verify with an appropriate
voltmeter that all capacitors have discharged. Failure to
disconnect power and discharge capacitors before
servicing could result in death or serious injury.
•
Ensure that there is no voltage being applied to the
compressor terminals.
•
Evacuate the unit to 500 microns.
•
Hold vacuum for 30 minutes.
•
Rapid pressure rise indicates a leak; locate and repair
the leak.
•
Slow pressure rise indicates one of two possibilities:
–
A small leak, indicated by a continuous rise in
pressure.
–
Moisture in the system, indicated by a slow rise in
pressure and leveling-out at a pressure equivalent
to the moisture level. If this occurs, break the
vacuum with dry nitrogen and repeat evacuation
process to 500 micron.
•
Once system is leak-tight, connect compressor repeat
the vacuum procedure, break vacuum with dry
nitrogen and evacuate to 500 microns. The vacuum
should be able to be maintained for four hours. Isolate
the vacuum pump so that the vacuum gauge only
reads the system pressure.
•
Vacuum must be measured in the refrigeration system
and not at the vacuum pump.
