Use and Care Manual

Troubleshooting 15
2. Field Maintenance
Possible causes of trouble
Power failure
Blown fuse or varistor
Loose connecons
Shorted or broken wires Safety device opens
Faulty thermostat / room temperature sensor Wrong seng place of temperature sensor
Faulty transformer
Shorted or open capacitor
Faulty magnec contactor for compressor Faulty magnec contactor for fan
Low voltage
Faulty stepping motor
Shorted or grounded compressor Shorted or grounded fan motor
Unit will not start
Compressor will not start but fans run
Compressor and condenser (outdoor) fan will not start
Evaporator (indoor) fan will not start
Condenser (Outdoor) fan will not start
Unit runs, but shortly stops
Compressor short-cycles due to overload
High discharge pressure
Low discharge pressure
High sucon pressure
Low sucon pressure
Unit runs connuously but insucient cooling
Too cool
Compressor is noisy
Horizontal louver can not revolve
Test method / remedy
Test voltage Inspect fuse type & size
Inspect connecons - ghten
Test circuits with tester
Test connuity of safety device
Test connuity of thermostat / sensor & wiring
Place the temperature sensor at the central of the air inlet grille Check control circuit with tester Check capacitor with tester Test connuity of coil & contacts
Test connuity of coil & contacts
Test voltage Replace the stepping moto
r
Check resistance with mulmeter Check resistance with mulmeter
Electrical Circuit