Table 5-l. Direct support troubleshooting-Continued.

TM 5-4120-386-14

Table 5-1. Direct support troubleshooting-Continued.

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

2. COMPRESSOR STARTS, BUT STOPS AT ONCE - "SHORT CYCLES" - Continued

Install pressure gages in system (paragraph 5-16) and check system

Step 6.

pressures to see whether an overcharge of refrigerant is indicated.

If overcharge is indicated, partially discharge the system and

retest.

3. INSUFFICIENT COOLING

Feel dehydrator to see whether it is cold to the touch, or is frosted or

Step 1.

sweating.

If so, replace dehydrator. (Refer to paragraph 5-17.)

Step 2. Check input and discharge sides of solenoid valves for temperature

difference, Abnormally cold discharge indicates leakage or obstruction.

Replace faulty solenoid valves. (Refer to paragraph 5-20.)

Step 3. Check evaporator coil for over-all temperature.

If part of coil is relatively warm, and evaporator inlet is sweaty

or frosty, expansion valve may be obstructed or damaged.

Step 4. Check liquid sight indicator for bubbles or cloudiness, which indicates

insufficient refrigerant.

Recharge system after checking for and repairing leaks. (Refer

to paragraphs 5-15 through 5-16.)

Step 5. Check for low discharge pressure to see whether compressor is

pumping. (Refer to table 5-2 for normal pressures.)

Replace faulty compressor. (Refer to paragraph 5-28.)

5-4