Unit Operates Long Or Continuously In Cooling - Carrier SUPRA 850Mt Operation And Service Manual

INDICATION / TROUBLE
5.3.3

Unit operates long or continuously in cooling

Container
Refrigeration system
Compressor
5.3.4 Unit will not heat or has insufficient heating
Refrigeration
Compressor
Engine does not develop full rpm
5.3.5 Defrost cycle malfunction
Will not initiate defrost
automatically
Will not initiate defrost manually
Initiates but does not defrost
Frequent defrost
Does not terminate or cycles on
defrost
5.3.6 Abnormal pressure
5.3.6.1 Cooling
High discharge pressure
Low discharge pressure
High suction pressure
POSSIBLE CAUSES
Hot Load
Defective box insulation or air leak
Abnormal pressure
Temperature controller malfunction
Defective
Abnormal pressure
Temperature controller malfunction
Hot gas valve malfunction
Compressor drive defective
Compressor defective
Speed control linkage
Engine malfunction
Defrost thermostats (DTT) open or defective
Loose terminal connections
Air sensing tubes defective or disconnected
Microprocessor defective
Loose terminal connections
Defrost thermostats (DTT) open or defective
Glow/Defrost switch defective
Hot gas valve malfunction
Defrost relay (DR) defective
Defrost timer to be adjusted
Wet load
Defrost thermostats (DTT) shorted closed
Glow/Defrost switch defective
Condenser coil dirty
Condenser fan defective
V-belt broken or loose
Discharge check valve restricted
Noncondensibles or refrigerant overcharge
Compressor valves(s) worn or broken
Hot gas valve malfunction
Compressor valves(s) worn or broken
Compressor gasket(s) defective
Hot gas valve malfunction
5-4
REFERENCE
SECTION
Allow time to
pull down
Correct
5.3.6
5.3.8
4.9
5.3.6
5.3.8
5.3.11
4.9
4.9
4.3.4
5.1
Replace
Tighten
Check
Replace
Tighten
Replace
Replace
5.3.11
Replace
2.8.6
Normal
Replace
Replace
4.16.2
Check
4.4
Replace
Replace
4.9
5.3.11
4.9
4.9
2.9.2
62--611XX- -20 (03/04)