Unit stops and F4 is displayed; often associated with high outdoor temperature or dirty condenser.

Safety first: Turn off the outdoor unit breaker before cleaning or servicing.

• Clear surroundings: Ensure at least the manufacturer-recommended clearance around the outdoor unit (typically 30–50 cm sides, more above). Remove any obstructions.
• Clean condenser coil: Use a garden hose with low pressure to rinse dirt from the coil fins from inside out. Avoid high pressure that can bend fins.
• Check outdoor fan: Confirm the fan runs at full speed when the unit is cooling. If it is slow, intermittent, or not running, replace the outdoor fan motor.
• Thermistor check: Verify the discharge pipe sensor is properly attached and insulated. Replace if faulty.
• Refrigerant charge: If F4 persists with clean coil and good airflow, a technician should check for overcharge or system restrictions using gauges and Sharp service data.