Unit displays F5 and may shut down unexpectedly during operation.

Safety: Unplug the unit. Refrigerant circuits are sealed and under high pressure; do not attempt to open the system without proper certification.

Steps:

• Improve airflow: Clean the condenser coil thoroughly with a soft brush or vacuum. Ensure at least several inches of clearance around the exhaust or rear of the unit.
• Check condenser fan: Verify that the condenser fan motor starts reliably and runs at full speed. Replace if slow, noisy, or not starting.
• Inspect high-pressure switch (if accessible): Some NewAir models use a pressure switch or sensor on the discharge line. Check wiring and connectors for damage.
• Ambient conditions: Avoid operating the unit in extremely high ambient temperatures beyond its rated specification, as this can trigger F5.
• Professional service: If airflow and fan operation are correct but F5 persists, the issue may be refrigerant overcharge, restriction, or a faulty pressure sensor. Contact a licensed HVAC technician to diagnose the sealed system.