Freezer shows E4 and may not defrost properly; heavy ice build-up on evaporator and poor cooling.

Safety warning: Unplug the freezer and allow sharp metal parts to warm slightly before working near the evaporator to avoid cuts and frostbite.

Steps to resolve E4 (defrost sensor/thermostat):

• 1. Manually defrost: Open the door, remove drawers, and let the unit defrost fully (this may take several hours). Do not chip ice with sharp tools to avoid damaging the evaporator.
• 2. Remove evaporator cover: Once ice has melted, remove the rear inner panel to expose the evaporator and defrost components.
• 3. Locate defrost sensor/thermostat: On many Leisure freezers, a defrost NTC or bi-metal thermostat is clipped to the evaporator tubing near the top or side. It may be wrapped in foil or insulation.
• 4. Test continuity: For a bi-metal thermostat, check continuity with a multimeter at room temperature; some types are closed only when cold. For an NTC, measure resistance and compare to expected values. Replace if open circuit or out of specification.
• 5. Inspect wiring: Follow the sensor wires back to the harness and PCB. Repair any damaged insulation and ensure connectors are firmly seated.
• 6. Replace faulty parts: Install a new Leisure defrost thermostat or defrost NTC sensor as per your model. Clip it securely to the evaporator tube in the same location and orientation.
• 7. Reassemble and test: Refit the evaporator cover, restore power, and run the freezer for 24 hours. Check that frost pattern is even and that E4 does not reappear.
• 8. If E4 persists: The main control PCB defrost circuit may be defective. Replacement of the main control PCB is recommended and may require a professional technician.