Table 5-l. Direct support troubleshooting-Continued.

TM 5-4120-386-14

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

7. LOW HEAT OR NO HEAT - Continued

Disconnect and remove heater elements, and apply 115-volt ac power

Step 3.

to check for open circuit in element. Element should heat.

Replace faulty heating elements (Refer to paragraph 4-33.)

Step 4. Check continuity of high-pressure cutout switch at room temperature.

Continuity should exist.

a. If continuity does not exist, press reset button and

recheck. (Refer to paragraph 5-23.)

b. Replace faulty switch.

Disconnect heater relay. Apply 24-28 volts dc to actuate relay and

Step 5.

check continuity at secondary terminals. Continuity should exist.

Replace faulty relay. (Refer to paragraph 4-25.)

Step 6. Check operation of evaporator fan and motor.

Repair or replace faulty fan or motor. (Refer to paragraphs

4-30, 4-31 and 5-7.)

5-7