Common Faults in Refrigeration Systems and Handling Methods

2025-02-26

Evaporator liquid return: Adjust the opening degree of the expansion valve to increase the superheat of the refrigerant return gas.
Excessive refrigerant dissolved in the oil separator.

Non - condensable gas in the system: Release air at the highest point of the exhaust pipe.
Condenser fouling or dust accumulation: Clean the condenser.
Insufficient cooling water volume: Take measures to increase the water volume and improve the working environment of the condenser.
Excessive refrigerant: Remove the excess refrigerant.
Insufficient opening of the exhaust pipeline: Fully open the relevant valves.
Incorrect setting or damage of the high - low pressure controller: Adjust or replace the high - low pressure controller.

Serious leakage in the exhaust pipeline or compressor exhaust valve plate: Replace the valve plate and repair the leakage in the exhaust pipeline.
Improper adjustment or failure of energy regulation: Correctly adjust the energy mechanism.

Excessively high discharge temperature, operation of the temperature protection module

Part - load operation: Adjust the operation control process of the compressor to ensure suitable operating conditions.
Low suction pressure: Refer to "low suction pressure fault" for details.
Short - circuit of the compressor stator winding: Repair or replace the compressor motor.
Damage to the temperature protection module: Replace the temperature protection module.

The expansion valve opening is too small or the flow hole is blocked by ice: Targetedly eliminate the expansion valve fault.
Evaporator fouling: Clean the evaporator.
The suction valve is not fully opened: Fully open the suction valve.
Blockage in the liquid pipe, insufficient opening of the valve on the liquid pipe, or filter blockage: Remove the blockage and fully open the valve.
Insufficient refrigerant charge: Check if the system is leaking and replenish the refrigerant.
Excessive lubricating oil: Check the lubricating oil system to make it normal and drain the excess oil.

Valve plate or foreign object breaks and falls into the cylinder: Remove the foreign object and repair the damaged parts.
Oil slugging due to excessive lubricating oil: Stop the machine immediately, check the lubricating oil system to make it normal, and drain the excess liquid.
Refrigerant liquid slugging: Stop the machine immediately and adjust the expansion valve.
Loose compressor base angles: Tighten the base angle bolts.

Power supply or circuit fault: Repair the circuit.
Abnormal oil pressure, activation of the oil pressure protection: Check the oil circuit.
Activation of the high - low pressure controller: Refer to "high discharge pressure fault" for details.
Faulty solenoid valve causing low - pressure protection: Replace the solenoid valve.
The oil pressure controller is not reset: Reset the oil pressure controller.
Activation of the temperature protection module: Refer to "excessively high discharge temperature" fault for details.

Damaged oil gauge, blocked oil circuit: Check, calibrate or replace the pressure gauge, and clean and blow through the oil pipe.
Low oil level: Add lubricating oil.
Excessive clearance in the oil pump: Adjust the oil pump clearance or replace the components.
Excessive refrigerant dissolved in the oil: Reduce the opening degree of the expansion valve.

Insufficient lubricating oil: Observe the oil sight glass and add an appropriate amount of lubricating oil.
Faulty oil flow module: Check or replace the oil flow module.
Faulty oil flow switch: Check or replace the oil flow switch.
Faulty oil circuit solenoid valve: Check or replace the oil circuit solenoid valve.

Compressor locked - rotor: Check the compressor.
Compressor over - load operation: Commonly seen in the cold air system, start it in stages.
Abnormal power supply or circuit: Check the power supply voltage and phase sequence. Repair the circuit.
The set value of the air - switch current does not match the motor: Adjust the set value of the air - switch.

Damaged fan bearing: Replace the bearing.
Blades jammed: Adjust the blades and eliminate the fault.
Blocked air duct: Clear the air duct.
Power supply or circuit fault: Check the power supply voltage and phase sequence. Repair the circuit.
The set value of the air - switch current does not match the motor: Adjust the set value of the air - switch.

Water pump running idle or locked - rotor: Check if the water circuit is normal.
Abnormal power supply or circuit: Check the power supply voltage and phase sequence. Repair the circuit.
The set value of the air - switch current does not match the motor: Adjust the set value of the air - switch.

No water supply source or pipeline valve closed: Check the water source or the cooling water pipeline.
Dirty and blocked water filter: Clean the water filter.
Air in the pipeline: Vent the air in the pipeline.
Faulty flow switch or abnormal circuit: Repair or replace the water flow switch and check the control circuit.