Freezer shows E04 and may not defrost properly, with heavy ice buildup on the evaporator.

Safety first: Disconnect the freezer from mains power before accessing internal components. Be cautious of sharp evaporator fins.

• Defrost the unit: If the evaporator is heavily iced, leave the freezer unplugged with the door open for several hours or use a fan to speed up defrosting. Do not use sharp tools or heat guns.
• Access evaporator and defrost components: Remove baskets and the internal rear panel to expose the evaporator, defrost heater, and defrost NTC sensor.
• Inspect the defrost heater: The heater is usually a metal or glass-encased element at the base or woven through the evaporator. Look for breaks, burn marks, or disconnected wires.
• Test heater continuity: Disconnect heater leads and measure resistance with a multimeter. An open circuit indicates a failed heater that must be replaced with a Candy-compatible defrost heater.
• Check defrost NTC sensor: Measure resistance of the defrost sensor at room temperature and compare to expected NTC values. Replace if open, shorted, or far out of range.
• Inspect thermal fuse/thermostat (if fitted): Some Candy freezers include a thermal fuse or bimetal thermostat in series with the heater. Test for continuity; replace if open.
• Evaluate control board: If heater and sensors are good, the main control board defrost relay or triac may be faulty. Visual inspection may show burnt spots; replacement of the PCB is typically required.
• Reassemble and test: Refit all panels and components, plug the freezer back in, and monitor for normal defrost operation and clearing of E04.

Warning: Working on the defrost circuit involves mains voltage. If you are not experienced with electrical testing, seek professional service.