December 1997
21
RS1300003 Rev. 0
Symptom
Possible Causes
Corrective Action
Defrost thermostat faulty
Check defrost thermostat. Replace if
defective.
Evaporator fan faulty
Check fan motor. Replace if
defective.
Defrost heater remains open
Check defrost heater continuity.
Replace if faulty.
Defrost control faulty
Check control and replace if
defective.
Open wire or connector
Check wiring and connections.
Repair as necessary.
Frost or ice on evaporator
Refrigerant shortage or restriction
Check for leak or restriction. Repair,
evacuate and recharge system.
Loose wire or thermostat
connections
Check wiring and connections.
Repair as necessary.
Supply voltage out of specification
Check input voltage. Correct any
supply problems.
Overload protector open
Check overload protector for
continuity. If open, replace overload.
Note: Ensure
overload/compressor are below
trip temperature before testing.
Faulty compressor motor capacitor
Check capacitor for open/short.
Replace if necessary.
Note: Discharge capacitor before
testing.
Faulty fan motor
Check fan motor. Replace if
defective.
Restricted air flow
Check condenser and grille for dirt.
Clean.
Unit starts and stops frequently
(cycles on and off)
Refrigerant shortage or restriction
Check for leak or restriction. Repair,
evacuate and recharge system.
Troubleshooting Chart
To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit and discharge
capacitor through a 10,000 ohm resistor before attempting to service, unless test procedures require power to be
connected. Ensure all ground wires are connected before certifying unit as repaired and/or operational.
!
WARNING
