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- Phone：0086-13705113637
- Tell：0086-0515-88809180
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- Address：No. 18, Rongguang Road, National High-tech Park, Yancheng City, Jiangsu Province
The overheating protection of the air conditioning compressor is the core safety mechanism of the equipment. When the temperature of the compressor housing exceeds the safety limit, the operating current exceeds the standard, or the exhaust temperature is abnormal, the built-in thermal protector and the motherboard temperature control module will automatically cut off the power supply to the compressor to prevent irreversible faults such as insulation burnout of the coil, shaft seizure, and compressor explosion. Common faults can be referred to the following causes.
1. Cooling system failure
1. Condenser blockage of the outdoor unit
Reason: During summer, dust, pollen, and oil deposits adhere to the fins of the condenser, blocking the air duct and causing a significant drop in cooling efficiency; the outdoor unit is installed in a closed balcony, awning, or a narrow machine position, or is blocked by debris, resulting in extremely poor ventilation. When the ambient temperature exceeds 43℃ in summer, the cooling load of the outdoor unit is excessive, and it is highly likely to trigger the thermal protection.
Maintenance: Use a high-pressure water gun to spray low-pressure water on the fins of the condenser to completely remove the blocked debris; clear the surrounding obstructions of the outdoor unit to ensure a ≥30cm ventilation space around the body and no obstruction on the top; install an exhaust device in the machine position to force convective cooling.
2. Abnormal/failed operation of the outdoor fan
Reason: The capacitor of the fan motor ages and deteriorates, the bearing of the fan motor is lacking lubrication and wears out, the fan blade is deformed and stuck, resulting in insufficient air volume, and the heat from the condenser cannot be quickly dissipated, causing the compressor to accumulate heat continuously.
Maintenance: Test the capacitance of the fan motor, if the deviation exceeds 20%, replace it with the same specification capacitor; if there is abnormal noise or slow rotation speed, add high-temperature-resistant lubricating oil to the motor winding, and directly replace the motor if the motor winding is aged and burned; correct the deformed fan blade and tighten loose parts.
II. Abnormal Parameters of the Refrigeration System
1. Abnormal refrigerant charging (excessive/insufficient)
Reason: Insufficient refrigerant will cause the compressor's return gas to be overheated, losing its cooling effect and causing the shell to heat up rapidly; excessive refrigerant will result in a sudden increase in system pressure, a significant increase in compressor load, and excessive temperature rise, both of which will trigger thermal protection.
Maintenance: Use a pressure gauge to test the high and low pressures of the system, and calibrate the pressure values based on the ambient temperature; after evacuating the system, add the original factory standard refrigerant in a quantitative manner to prevent adding or reducing refrigerant based on experience.
2. System blockage
Reason: Blockage of the dryer filter, capillary tube/expand valve due to ice, dirt, causing poor refrigeration circulation, insufficient refrigerant flow, compressor running without load and overheating, abnormal load.
Maintenance: Replace the dryer filter, clean or unclog the throttling components; if the system is waterlogged and damp, completely evacuate it and replace the refrigerant and refrigerating oil.
3. Failure or lack of refrigerating oil
Reason: Long-term use of refrigerating oil leads to deterioration and carbonization, or the system leaks oil or lacks oil, increasing friction resistance of the piston and bearings inside the compressor, generating a large amount of mechanical heat, and losing its lubrication and cooling functions.
Maintenance: Completely replace the same model original factory refrigerating oil (R134a/R410A corresponding to special POE oil), check the weld points and interfaces of the pipeline to identify leaks, and add the standard amount of refrigerating oil after repairing the leaks.
