Refrigerator not defrosting properly, repeated frost, E20 error

Safety first: Unplug the refrigerator before testing or replacing any electrical components. Avoid contact with wet surfaces.

Steps:

• Access evaporator: Remove freezer rear panel to expose the defrost heater and wiring.
• Visual inspection: Look for burnt heater sections, melted insulation, or wires touching metal parts.
• Test heater: Disconnect heater leads and measure resistance. A very low resistance (near 0 Ω) or visible short to ground indicates a problem.
• Inspect wiring harness: Repair or replace any damaged wiring, ensuring proper insulation and routing.
• Check control board: If the heater and wiring are good, the defrost relay or triac on the main board may be shorted and require board replacement.

Warning: Do not bypass safety devices or operate the unit with suspected electrical shorts. Contact a professional if unsure.