Periodic Inspection
Si50-203
6
Semi-Hermetic Single Screw Compressor Version III
2. Changing Refrigerating Oil
Oil degrades after many hours of operation and due to aging. Replace oil regularly after
7,500 hours of operation or four years, whichever comes first.
(
Changing Procedure
)
(1) Perform a pump down operation to reduce pressure inside the compressor.
(2) Release the internal pressure of the compressor.
Loosen the flare nut at the service port (with check valve) of the compressor (see Fig. 3-2).
Remove the partition lid, then tighten the flare nut to discharge refrigerant from the
compressor. To loosen and tighten the flare nut, use two wrenches to turn the flare nut and
keep the other nut stationary.
Fig. 3-2 Service port and oil charge port locations
(3) After confirming that refrigerant is completely discharged, drain oil from the two drain ports
located on the lower section of the casing.
The compressor rotates in the reverse direction when it stops operating. This causes oil to
remain in the suction side. Therefore, be sure to drain oil from the two drain ports.
Fig. 3-3 Drain port locations
Summary of Contents for ZH(C)3LSF
Page 48: ...Si50 203 ii Index...
