AIR CONDITIONING (Cont) - TM-55-1905-223-24-170218

TM 55-1905-223-24-17

Table 4-1. Troubleshooting - CONT

Malfunction

Test or Inspection

Corrective Action

AIR CONDITIONING - CONT

Replace valve plate in semi-hermetic compressor in A/C-2 (paragraph 4-9).

STEP 3.

Check to see if thermostat is stuck. Replace thermostat (paragraph 4-14).

STEP 4.

Check for leaking piston rings or cylinder sleeves in semi-hermetic type compressor (A/C-

2; accommodations). Replace piston rings or compressor as required (paragraph 4-19).

15.

Compressor noises.

STEP 1.

Check for slugging due to refrigerant floodback (on expansion valve equipped unit; A/C-2,

accommodations). Make sure the thermal bulb on the expansion valve is firmly attached

to the suction line. Correct as required.

STEP 2.

Check for hydraulic knock due to excess oil in circulation. Refer to Item 14 of this table.

STEP 3.

Check for worn pistons, connecting rods, or bearings in semi-hermetic compressor (A/C-2;

accommodations). Replace as required (paragraph 4-9).

16.

Hissing sound.

STEP 1.

Check for insufficient refrigerant flow due to low charge. Find and repair leak. Evacuate

and recharge system with R-22 (Malfunction 10 and paragraph 4-10).

17.

No cooling - blower does not run.

STEP 1.

Check for fan motor defective. Replace fan motor (paragraph 4-15).

18.

No cooling - blower running.

STEP 1.

Check for air in system. Purge, (Malfunction 4). If purging is not successful, remove

charge, evacuate, and recharge system with R-22 (paragraph 4-10).

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