Carrier 69NT40-541-001, Operation And Service

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T-316 7–8
7.7.3 Adding Refrigerant to System (Partial Charge)
a. Examine the unit refrigerant system for any evidence of leaks. Repair as necessary. (Refer to Section 7.5 .)
b. Maintain the conditions outlined in Section 7.7.1 .
c. Fully backseat the suction service valve and remove the service port cap.
d. Connect charging line between suction service valve port and cylinder of refrigerant R-134a. Open VAPOR
valve.
e. Partially frontseat (turn clockwise) the suction service valve and slowly add charge until the refrigerant
appears at the proper level.
7.8 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 500 mm/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 Section 7.8.6 .)
4. A compressor terminal wiring kit must be ordered as a separate item when ordering replacement com-
pressor. Appropriate installation instructions are included with kit.
5. Refer to Table 7–6 and Table 7–7 for applicable compressor wear limits and torque values.
6. Refer to Figure 7.33 for charts on compressor pressure, temperature and motor current curves.
7.8.1 Removal and Replacement of Compressor
a. Remove the protective guard from lower section of the unit.
b. Pump down low side (refer to Section 7.4 ) or frontseat compressor service valves and remove refrigerant
from compressor using a refrigerant recovery system.
c. Locate the compressor junction box. Tag and disconnect 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 Section 3.2 for weight of compressor.
g. Remove high pressure switch (HPS) from compressor and check operation of switch (refer to Section 7.9.2 ).