TM 9-4120-399-14
Table 5-1. Direct Support Troubleshooting. (Continued).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
3.
SUCTION PRESSURE TOO HIGH. - Continued.
Step 10. Check sight glass for evidence of bubbles and refrigeration level that indicate
severe refrigerant blockage.
Replace clogged filter/dryer dehydrator per para. 5-15.
Step 11. Check the sight glass for moisture in the system (Yellow indications).
4.
SUCTION PRESSURE TOO HIGH.
Step 2. Check condition of liquid quench expansion valve bulb. Check to see that
it is properly contacted to suction line.
Replace liquid quench expansion valve if bulb damaged per para. 5-21.
Secure bulb to suction line if loose.
Step 3. Check performance of liquid quench expansion valve.
Replace defective liquid quench expansion valve per para. 5-21.
Section III. DIRECT SUPPORT
MAINTENANCE PROCEDURES
a. The procedures in this section cover items which appear in the direct support
maintenance level on the Maintenance Allocation Chart (MAC) which is in Appendix B.
procedures which may need to be performed at some point during the specific repair or
replacement of items within the refrigeration system. Paragraphs 5-6 through 5-12 cover these
general procedures.