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6.8 COMPRESSOR
WARNING
Make sure power to the unit is OFF and
power plug disconnected before replacing
the compressor.
NOTES
1. The compressor should not operate in a
vacuum greater than 500mm/hg (20
inches/hg).
2. The service replacement compressor is
sold without shutoff valves (but with valve
pads), and without terminal box and cover.
Customer should retain the original
terminal box, cover, and high pressure
switch for use on replacement compressor.
3. Check oil level in service replacement
compressor (refer to paragraph 6.8.6).
4. A compressor terminal wiring kit must be
ordered as a separate item when ordering
replacement compressor. Appropriate
installation instructions are included with
kit.
5. Refer to Table 6-7 and Table 6-8 for
applicable compressor wear limits and
torque values.
6. Refer to Figure
compressor pressure, temperature and
motor current curves.
6.8.1 Removal and Replacement of Compressor
a. Remove the protective guard from lower section of
the unit.
b. Pump down low side (refer to paragraph 6.4) or front-
seat compressor service valves and remove refriger-
ant from compressor using a refrigerant recovery
system.
c. Locate the compressor junction box. Tag and discon-
nect wiring from compressor terminals and remove
compressor junction box.
d. Loosen service valve mounting bolts, break seal, and
then remove bolts.
e. Remove compressor plate mounting bolts.
f. Remove compressor and mounting plate. Refer to
paragraph 2.2 for weight of compressor.
1
2
3
4
5
6
7
8
10
11
12
13
14
15
9
16
1. Discharge Valve
Flange
2. High Side Pressure
Connection
3. Low Side Pressure
Connection
4. Suction Valve Flange
5. Motor End Cover
6. Serial/Model No. Plate
7. Crankcase Heater
8. Bottom Plate
9. Sight Glass
10. Oil Drain Plug
11. Oil Charging Valve
12. Bearing Head
13. Oil Pump
14. Oil Fill Plug
15. Cylinder Head
16. Valve Plate
Figure 6-5 Compressor
g. Remove high pressure switch (HPS) from compres-
sor and check operation of switch (refer to paragraph
h. Remove compressor mounting bolts from mounting
plate and install mounting plate on replacement com-
pressor.
i. Install replacement compressor terminal wiring kit,
following instructions included with kit.
j. Install high pressure switch on compressor.
k. Install compressor and mounting plate in unit.
l. Connect junction box(es) to compressor and connect
all wiring per wiring diagram. Install junction box
cover(s).
m.Install new gaskets on service valves.
n. Install mounting bolts in service valves and torque to
2.77 to 4.15mkg (20-30ft/lb).
o. Attach two hoses (with hand valves near vacuum
pump) to the suction and discharge service valves.
Dehydrate and evacuate compressor to 500 microns
(75.9 cm Hg vacuum = 29.90 inches Hg vacuum).
Turn off valves on both hoses to pump.
p. Fully backseat (open) both suction and discharge
service valves.
q. Remove vacuum pump lines.
r. Start unit and check refrigerant charge (refer to para-
graph 6.7).
s. Check moisture-liquid indicator for wetness. Change
filter-drier if necessary (refer to paragraph 6.13).
t. Check compressor oil level per paragraph 6.8.6. Add
oil if necessary.