FAXA-SVX01B-EN
79
Maintenance
maintenance
procedures
1. Charge enough refrigerant and dry
nitrogen into the system to raise the
pressure to 100 psig.
2. Use a halogen leak detector, halide
torch, or soap bubbles to check for
leaks. Check interconnecting piping
joints, the evaporator coil connections,
and all accessory connections.
3. If a leak is detected, release the test
pressure, break the connections and
reassemble it as a new joint, using
proper brazing techniques.
4. If no leak is detected, use nitrogen to
increase the test pressure to 150 psig
and repeat the leak test. Also, use soap
bubbles to check for leaks when
nitrogen is added. Never pressurize the
unit above 200 psig.
5. Retest the system to make sure new
connections are solid.
6. If a leak is suspected after the system is
fully charged with refrigerant, use a
halogen leak detector, halide torch, or
soap bubbles to check for leaks.
Refrigerant Evacuation
For field evacuation, use a rotary style
vacuum pump capable of pulling a
vacuum of 100 microns or less.
When connecting the vacuum pump to a
refrigeration system, it is important to
manifold the pump to both the high and
low side of the system. Follow the pump
manufacturer’s directions.
CAUTION
Motor winding damage!
Do not use a Meg ohm meter or apply
power to the winding of a compressor
while it is under a deep vacuum. This
may damage the motor windings.
WARNING
Hazardous pressures!
If using a heat source to raise the tank
pressure when removing refrigerant,
use only warm water or heat blankets
to raise the tank temperature. Do not
exceed 150°F. Do not, under any
circumstances, apply direct flame to
any portion of the refrigerant cylinder.
Failure to follow these safety
precautions can cause a violet
explosion that can cause death or
serious injury.
Charging the Refrigerant System
CAUTION
Freezing temperatures!
Do not allow liquid refrigerant to
contact skin. If it does, treat the injury
similar to frostbite. Slowly warm the
afffected area with lukewarm water
and seek immediate medical
attention. Direct contact with liquid
refrigerant may cause minor or
moderate injury.
To completely charge the system, charge
gaseous refrigerant into the suction line
shrader valve with the unit running.
However, make sure that some
refrigerant is present in each circuit
before starting the compressors. The
refrigerant container should be upright so
that gaseous refrigerant is drawn off the
top.
Note: Charge each circuit with R134a.
See Table M-GI-1 on page 70.
CAUTION
Motor winding damage!
Do not use a megohm meter or apply
voltage greater than 50 DVC to a
compressor motor winding while it is
under a deep vacuum. Voltage sparkover
may damage the motor windings.
Note: Refer to Table M-GI-1 on page 70
for POE, oil type. Oil type is different for
Trane compressors vs. Copeland
compressors. Failure to comply may
cause premature compressor failure and
void compressor warranty.
CAUTION
Compressor damage!
Never manually or automatically pump
down system below 7 psig. This will
cause the compressor to operate in a
vacuum and result in compressor
damage.
Summary of Contents for FADA
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