Abnormal Noises Or Vibrations; Evaporator Air Flow Or Restricted Air Flow; Expansion Valve Malfunction; Or Insufficient Heating - United Technologies Carrier TRANSICOLD 68RM35-604-20 Operation And Service

INDICATION/
TROUBLE
3.4

ABNORMAL NOISES OR VIBRATIONS

Compressor
Condenser or evaporator fans
3.5 ELECTRONIC THERMOSTAT MALFUNCTION
Will not control
3.6 NO EVAPORATOR AIR FLOW OR RESTRICTED AIR FLOW
Air flow through coil blocked
No or partial evaporator air flow
3.7

EXPANSION VALVE MALFUNCTION

Low suction pressure with high
superheat
Low superheat and liquid slugging
in the compressor
Fluctuating suction pressure
3.8 NO OR INSUFFICIENT HEATING
Insufficient heating
No Heating
T-288
Table 3-1. Troubleshooting procedures - Continued
Loose mounting hardware
Worn bearings
Worn or broken valves
Liquid slugging
Insufficient oil
Clutch loose, rubbing or is defective
V-belt cracked, worn or loose
Loose mounting hardware
Defective bearings
Blade interference
Blade missing or broken
Thermostat defective
Sensor defective
Defective wiring
Coil frosted over
Dirty coil
Dirty filter
Motor running in reverse (wiring polarity incorrect)
Motor(s) defective
Motor brushes defective
Evaporator fan loose or defective
Return air filter dirty
Icing of coil/dirty coil
Fan relays EFR1 OR EFR2 defective
Safety device open
Low refrigerant charge
Wax, oil or dirt plugging valve orifice
Ice formation at valve seat
Superheat setting too high
Power assembly failure
Loss of bulb charge
Broken capillary
Superheat setting too low
Ice or other foreign material holding valve open
Loose bulb
Improper bulb location or loose bulb installation
Low superheat setting
Dirty or plugged heater coil or filter
Coolant valve malfunction or plugged
Low coolant level
Coolant valve malfunction or plugged
Thermostat malfunction
Boost relay or pump malfunction
Safety device open
POSSIBLE CAUSES
3-2
REFERENCE
SECTION
Check/Tighten
See Note.
See Note.
3.7
4.18.2
Check
Check/Adjust
Check/Tighten
Replace
Check
Check/Replace
Replace
Replace
Check
Defrost coil
Clean
Clean/Replace
Check/5.1
4.16
4.16
4.16
Clean/Replace
Defrost/Clean
1.5
1.4
4.9
Check
4.7
4.12
Replace
Replace
4.12
4.12
4.12
Check
4.12
4.12
Clean
Check
Check
Check/Replace
3.5
Repair/Replace
1.4