Fisher & Paykel RX256DT4X1 FP Service Manual page 74

321023
Symptom
Unit runs continuously.
Unit runs continuously. Temperature
normal.
Unit runs continuously. Temperature too
cold.
Noisy operation.
Frost or ice on evaporator.
Unit starts and stops frequently (cycles on
and off).
Possible Causes
Temperature control set too cold.
Dirty condenser or obstructed grille.
Poor door seal.
Interior light remains on.
Faulty condenser fan or evaporator fan. Check fan and wiring. Replace if
Faulty control.
Refrigerant shortage or restriction.
Refrigerant overcharge.
Air in system.
Ice on evaporator.
Faulty defrost thermostat.
Loose flooring or floor not firm.
Cabinet not level.
Tubing in contact with cabinet, other
tubing, or other metal.
Drip pan vibrating.
Fan hitting another part.
Worn fan motor bearings.
Compressor mounting grommets worn or
missing. Mounting hardware loose or
missing.
Free or loose parts causing or allowing
noise during operation.
Defrost thermostat faulty.
Evaporator fan faulty.
Defrost heater remains open.
Defrost control faulty.
Open wire or connector.
Refrigerant shortage or restriction.
Loose wire or thermostat connections.
Supply voltage out of specification.
Overload protector open.
Faulty compressor motor capacitor (some
compressors do not require motor
capacitor).
Faulty fan motor.
Restricted air flow.
Refrigerant shortage or restriction.
Compressor hot.
74
Corrective Action
Adjust temperature control.
Check condenser and grille. Clean.
Level cabinet. Adjust hinges. Replace
gasket.
Check switch. Replace if necessary.
necessary.
Test control. Replace if failed.
Check for leak or restriction. Repair,
evacuate and recharge system.
Check for overcharge. Evacuate and
recharge system.
Check for low side leak. Repair, evacuate
and recharge system.
See "Ice on evaporator".
Check thermostat. Replace if necessary.
Repair floor or brace floor.
Level cabinet.
Adjust tubing.
Adjust drain pan.
Ensure fan properly aligned and all
attaching hardware and brackets are tight
and not worn. Tighten or replace.
Check motor for loss of lubricant or worn
bearings. Replace if necessary.
Tighten hardware. Replace grommets if
necessary.
Inspect unit for parts that may have worked
free or loose or missing screws. Repair as
required.
Check defrost thermostat. Closes at
O O
-10 C / 14 F. 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 wiring and connections. Repair as
necessary.
Check input voltage. Correct any supply
problems.
Check overload protector for continuity. If
open, replace overload.
NOTE: Ensure overload/compressor are
below trip temperature before testing.
Check capacitor for open/short. Replace if
necessary.
NOTE: Discharge capacitor before testing.
Check fan motor. Replace if failed.
Check condenser and grille for dirt. Clean.
Check for leak or restriction. Repair,
evacuate and recharge system.
Check compressor current draw.