|
| |
Table 4-2. Troubleshooting Chart—Continued
Malfunction
3. Evaporator or condenser fan fails
to operate.
4. Compressor will not start.
5. Compressor starts but goes out on
overload.
4-4
Probable Cause
a. Main power cable disconnected.
b. Defective fan motor.
c. Evaporator or condenser fan
defective or binding.
d. Defective
condenser
motor
thermal protector.
e. Defective evaporator fan motor
thermal protector.
f. Defective receptacle or plug
connectors.
g. Defective high-low condenser fan
thermostatic switch.
h. Defective condenser fan relay.
i. Defective evaporator fan speed
control switch.
j. Mode selector switch improperly
adjusted or defective.
a. Compressor or control circuit
breakers or selector switch im-
properly set.
b. Contacts of high or low pressure
cutout switch open.
c. Loose electrical connections or
faulty wiring.
d. Open control circuit.
e. Defective circuit breaker.
f. Defective control transformer.
g. Defective rectifier.
h. Defective time delay relay.
i. Defective compressor relay.
j. Defective starting
relay or
capacitor (single phase com-
pressor).
k. Defective phase sequence relay
(three phase compressor).
l. Defective or tripped compressor
internal temperature overload
switch.
m. Defective compressor motor.
a. Condenser fan motor failure.
b. High head pressure.
c. Defective or “tripped” compressor
internal
temperature
overload
switch.
d. Improperly adjusted or defective
refrigerant control valves.
Corrective Action
a. Connect cable.
b. Replace motor (para 4-32 and 4-
40).
c. Relieve binding or replace fan
(para 4-38 and 4-40).
d. Replace thermal protector (para 4-
39).
e. Replace thermal protector (para 4-
39).
f. Replace connectors or receptacles
(para 4-33).
g. Replace thermostatic switch (para
4-41).
h. Replace defective relay (para 4-50
thru 4-54).
i. Replace defective switch (para 4-44
thru 4-48).
j. Replace a defective switch (para 4-
44 thru 4-48).
a. Reset controls properly.
b. Reset pressure switches. Report
deficiency to direct support
maintenance if condition con-
tinues.
c. Tighten loose connections. Repair
wiring if necessary.
d. Make continuity check of circuit
(para 4-12).
e. Replace defective control or
compresser circuit breaker (para
4-44 thru 4-48 or para 4-50 thru
4-54).
f. Replace defective transformer
(para 4-56).
g. Replace defective rectifier (para 4-
57).
h. Replace defective relay (para 4-50
thru 4-54).
i. Replace defective relay (para 4-50
thru 4-54).
j. Replace defective capacitor or relay
(para 4-61).
k. Replace defective relay (para 4-50
thru 4-54).
l. Allow unit to cool. Report
deficiency to direct support
maintenance if condition con-
tinues.
m. Check and report deficiency to
general support maintenance if
motor is defective.
a. Replace defective motor (para 4-
38 and 4-40).
b. Clean condenser coil and louvers.
Check fan for proper operation.
c. Allow unit to
cool. Report
deficiency to direct support
maintenance if condition con-
tinues.
d. Report condition to direct support
maintenance.
|
