Jenn-Air Service Manual page 19

Troubleshooting Chart
Symptom
Frost or ice on evaporator
!
WARNING
Possible Causes
Defrost thermostat faulty
Evaporator fan faulty
Defrost heater remains open
Defrost control faulty
Open wire or connector
Refrigerant shortage or restriction
Supply voltage out of specification
Faulty fan motor
Restricted air flow
Refrigerant shortage or restriction
Corrective Action
Check defrost thermostat. Replace if
failed.
Check fan motor. Replace if failed.
Check defrost heater continuity.
Replace if failed.
Check control and replace if failed.
Check wiring and connections.
Repair as necessary.
Check for leak or restriction. Repair,
evacuate and recharge system.
Check input voltage. Correct any
supply problems.
Check fan motor. Replace if failed.
Check condenser and grille for dirt.
Clean.
Check for leak or restriction. Repair,
evacuate and recharge system.