Carrier Transicold X4 7300, Operation & Service Manual

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62-11637 8–32
7. Align the gasket and the eight capscrews in the
mounting flange. Torque capscrews, in a diago-
nal pattern, 30 to 50 ft/lbs (40.7 to 67.8 Nm).
8. Leak check, evacuate & dehydrate, and charge
system as required. Refer to Section 8.7.2 ,
8.7.3 & 8.7.4 .
8.8.5 Compressor Oil Level
a. Checking Compressor Oil Level
NOTICE
An overcharge of oil will reduce system
capacity and possibly cause internal
compressor damage.
For this reason, Carrier Transicold re − manufactured
compressors now contain a reduced oil charge to com-
pensate for oil remaining in the system. A level slightly
below the minimum mark is acceptable until the oil
level can be checked using the following procedure:
1. Operate the unit in high speed, fully loaded cool
for at least 15 minutes. Unplug wires to the
unloaders if necessary to ensure six cylinder
operation.
NOTE
Check the oil sight glass on the compressor
to ensure that no foaming of the oil is pres-
ent after 15 minutes of operation. If the oil is
foaming check the refrigerant system for
flood-back of liquid refrigerant. Correct this
situation before performing step 2.
2. After 15 minutes, initiate a defrost cycle. This
will allow any residual oil to be returned to the
compressor.
NOTE
Operate the unit in defrost for only 3-5 min-
utes.
Do not allow the unit to terminate
defrost automatically . The sudden reduction
of crankcase pressure at defrost termination
could cause a temporary increase in oil circu-
lation and gave a false oil level reading.
3. After 3-5 minutes of defrost operation, turn the
unit off and wait 5-15 seconds. Observe the
compressor oil level in the sight glass. (See
Fig-
ure 8.28 ). Oil level should be between the Mini-
mum and Maximum marks.
Figure 8.28 Oil Level in Sight Glass
b. Adding Oil With Compressor In System
CAUTION
!
Use only Carrier Transicold approved
Polyol Ester Oil (POE). Buy quantities of
one gallon or less. When using this
hygroscopic oil, immediately reseal. Do
not leave container of oil open or contam-
ination will occur.
Two methods for adding oil are the oil pump method
and closed system method.
Oil Pump Method
One compressor oil pump that may be purchased is a
Robinair, part no. 14388. This oil pump adapts to a one
U.S. gallon (3.785 liters) metal refrigeration oil con-
tainer and pumps 2-1/2 ounces (0.0725 liters) per
stroke when connected to the oil fill (Item 12,
Figure
8.20 ). There is no need to remove pump from can after
each use.
When the compressor is in operation, the pump check
valve prevents the loss of refrigerant, while allowing the
technician to develop sufficient pressure to overcome
the operating suction pressure to add oil as necessary.
Backseat suction service valve and connect oil
charging hose to oil fill. Purge the oil hose at oil pump.
Add oil as necessary.
Closed System Method
NOTICE
Extreme care must be taken to ensure the
hose is immersed in the oil at all times.
Otherwise air and moisture will be drawn
into the compressor.
In an emergency where an oil pump is not available, oil
may be drawn into the compressor through the suction
service valve.
1. Pump down the compressor. Refer to Section
8.7.2 .
2. With both manifold gauge set valves front-
seated, leave the suction connection connected
to the compressor suction service valve port and
connect the common connection to a vacuum
pump. Remove the discharge hose from the
manifold gauge set; connect to the compressor
oil fill port (Item 12,
Figure 8.23 ), and immerse
the other end in a container of refrigeration oil.
Start the vacuum pump throttle the manifold
gauge set suction valve and pull a vacuum on
the compressor while watching the oil level in
the glass. Fill to minimum mark on crankcase.
Shutdown pump and remove oil fill line from the
oil fill port.
- Maximum
- Minimum