Error A3 — Compressor Temperature Protection Stop

What does A3 mean?

This error indicates that the compressor temperature has exceeded 110°C, causing the unit to stop operation as a protective measure. This specific error has been detected twice within a 24-hour period.

• The 3-way valve is not fully open, restricting refrigerant flow.
• The Electronic Expansion Valve (EEV) is defective or the strainer is clogged.
• Outdoor unit operation failure, possibly due to foreign matter on the heat exchanger.
• Failure of the compressor temperature thermistor, giving incorrect readings.
• Insufficient refrigerant in the system, which can lead to overheating.

Click steps to track your progress.

1. 1

   If accessible, check if the 3-way valve (for both gas and liquid lines) is fully open. If it was closed, open it and then restart the air conditioner.

2. 2

   Inspect the outdoor unit's heat exchanger for any visible foreign objects like leaves or debris and carefully remove them. Gently try to rotate the outdoor fan by hand to ensure it's not stuck.

3. 3

   If the issue persists, the system may require professional diagnosis for a defective EEV, clogged strainer, faulty thermistor, or a refrigerant leak. Contact a qualified service technician.