Parker Airtek MSC4000, User Manual

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MSC4000 - MSC15000 USER MANUAL
Do not charge vapor. The charge should be installed as quickly as possible so oil is return
to the compressor in a timely manner.
• If the system is short on refrigerant the it must be checked for leaks and repaired as necessary.
• Replace liquid filter-dryer whenever the system has been opened for service or exposed to air or water.
.
• If the system was repaired and or a section isolated and repaired it must be pulled into a vacuum (500 micron
minimum) before charging refrigerant.
• All units have a charging fitting on the evaporator shell. The unit must be charged through this fitting and/or the
liquid line service valve. The best way is to dump liquid into both ports with the dryer off, then start up and
continue feeding a full stream of liquid into the evaporator until charged.
• Additional oil is added at the factory to compensate for the migration with the refrigerant. If a compressor is
replaced, remove the drain plug from the evaporator shell to drain any excess oil trapped. If that isn’t possible,
it may be necessary to remove oil from the system after start-up. Excess oil is indicated by noisy and vibrating
compressor operation. If a replacement evaporator is installed, oil should be added. Prolonged operation with
insufficient charge or a bad TEV may cause oil to be trapped in the evaporator. If the compressor is still good, this
oil will return within a few minutes of operation with the correct conditions. For R-134 or R404a applications use
EMKARATE RL 32-3MAF, 150 SUS (ISO 32) (or equal) synthetic POE refrigeration oil.
• Note:
4000 SCFM & up: A complaint of pressure tripping only on start-up is usually due to air through the dryer
when it is shut down or low cooling pressure rather than overcharge. This causes refrigerant to migrate backwards
from the evaporator and overfill the high side of the system.