E4 displayed; unit stops and may beep; sometimes occurs during defrost or high load

Important: Overheating can damage the compressor. Turn the unit off and allow it to cool before further testing.

• Clean airflow paths: Remove and wash the air filters. Inspect indoor and outdoor coils on the Olimpia Splendid unit and gently clean dust with a soft brush or low-pressure air.
• Check for obstructions: Ensure at least the manufacturer-recommended clearance around the indoor and outdoor units. Remove any objects blocking vents.
• Inspect fan operation: Run the unit and verify that both indoor and outdoor fans start and reach full speed. If a fan is slow or not running, see fan-related entries.
• Locate discharge/defrost sensor: On some Olimpia Splendid models, E4 is triggered by a sensor on the compressor discharge line or outdoor coil. Check that this sensor is firmly attached and wiring is intact.
• Reset power: After cleaning and cooling, disconnect power for 10 minutes, then restart. Monitor operation; if E4 returns quickly, a sensor or PCB fault is likely.
• Advanced checks: If you have a multimeter and the service manual, test the discharge/defrost sensor resistance. Replace the sensor if readings are out of spec.
• Persistent E4: Could indicate a failing compressor or PCB. Due to refrigerant and high-voltage risks, contact an authorized Olimpia Splendid service center.