The multi-split unit's exhaust temperature alarm triggers a protective shutdown of the system. The unit monitors the exhaust temperature of the compressor and the high-pressure saturated temperature. When the temperature difference between the two is less than 10°C, the shutdown protection is triggered to prevent the compressor from burning out and the refrigerant from deteriorating, thus avoiding the expansion of faults.

I. Main Causes of Failure

1. Exhaust temperature sensor: Loosening, insulation failure, resistance drift, damage, and data distortion leading to false alarms.

2. Cooling mode: Indoor electronic expansion valve stuck, coil/mainboard abnormalities, valve failure.

3. Heating mode: Outdoor electronic expansion valve malfunction, refrigerant circulation imbalance.

4. System refrigerant: Excessive refrigerant injection, high high-pressure, and unmet temperature difference standards.

II. Troubleshooting and Maintenance Reference

Taking Gree multi-split units as an example, the general troubleshooting sequence is: exhaust temperature sensor → cooling valve components → heating valve components → refrigerant injection volume.

Step 1: Check the exhaust temperature sensor of the compressor

Visual inspection: Confirm that the sensor is firmly attached to the tube and the insulation is complete. Loose or damaged parts need to be re-fixed and insulated.

Resistance detection: Power off and detect the resistance of the sensor. Compare with the manufacturer's parameter table. Abnormal resistance or severe drift directly replace the same model sensor.

Note: The content and template of this article are collected from the internet and are copyrighted by the original authors; please notify us in time if there is any infringement and we will delete it promptly.