Table 1. Troubleshooting Procedures - Continued

TM 9-4120-425-14&P

DIRECT SUPPORT TROUBLESHOOTING PROCEDURES - Continued

0047-00

Table 1. Troubleshooting Procedures - Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

SUCTION PRESSURE TOO

Stop compressor and check

Remove bulb from ice water and

LOW - Continued

expansion valve Continued.

hold it in one hand to warm it. At

the same time, check the suction

line for rapid change of

temperature, which indicates

flood-through of liquid

refrigerant. If liquid floods

through valve, it is operating

satisfactorily. If not, valve or

remote bulb is faulty.

CAUTION

Do not let liquid flood back into

compressor or compressor will be

seriously damaged.

Replace faulty expansion valve.

(Refer to WP 0074-00.)

Feel filter-drier for temperature

Replace filter-drier. (Refer to WP

difference. Discharge end will

0066-00.)

feel cooler than input end if

clogged, or discharge end may be

frosty or sweaty (For low suction

pressure).

Expansion valve is stuck open.

10. SUCTION PRESSURE TOO

Check suction line and

Replace expansion valve. See WP

HIGH

accumulator for excessive

0074-00.

sweating and flood back of liquid

to compressor.

Repair or replace defective

Check for defective actuator

actuator cylinder. (Refer to WP

cylinder, broken or loose louver

0068-00.)

actuator cables.

Repair or replace louver actuator

cables. (Refer to WP 0032-00.)

Test for properly functioning

Test for defective expansion

expansion valve per WP 0074-00.

valve.

Replace defective expansion

valve. (Refer to WP 0074-00.)

0047-00-6