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SXIH-SVX01C-EN
Maintenance
WARNING
Hazard of Explosion!
Use only dry nitrogen with a pressure regulator for pressurizing unit. Do not use acetylene,
oxygen or compressed air or mixtures containing them for pressure testing. Do not use mixtures
of a hydrogen containing refrigerant and air above atmospheric pressure for pressure testing as
they may become flammable and could result in an explosion. Refrigerant, when used as a trace
gas should only be mixed with dry nitrogen for pressurizing units. Failure to follow these
recommendations could result in death or serious injury or equipment or property-only damage.
In the event of required system repair, leak test the liquid line, evaporator coil, and suction line at
pressures dictated by local codes, and using the following guidelines.
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.
5. Retest the system to make sure new connections are solid.
6. If a leak is suspected after the system has been 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
Compressor 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 Pressure!
If a heat source is required to raise the tank pressure during removal of refrigerant from
cylinders, use only warm water or heat blankets to raise the tank temperature. Do not exceed a
temperature of 150°F. Do not, under any circumstances apply direct flame to any portion of the
cylinder. Failure to follow these safety precautions could result in a violent explosion, which
could result in death or serious injury.
Charging the Refrigerant System
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.
CAUTION
Compressor Damage!
Do not allow liquid refrigerant to enter the suction line. Excessive liquid may damage the
compressor.
