Compressor failure and elimination

Compressor failure and elimination The compressor is the heart of the refrigeration system. It sucks low-temperature and low-pressure refrigerant gas from the suction pipe, drives the piston to compress it through the operation of the motor, and discharges high-temperature and high-pressure refrigerant liquid to the exhaust pipe to provide power for the refrigeration cycle. Thus, a refrigeration cycle of compression, condensation, evaporation and heat absorption is realized. Now let's take a look at the common faults and troubleshooting methods of the compressor: 1. Sudden shutdown of the compressor during operation: The reasons for the sudden shutdown of the compressor during operation are: the suction pressure is too low, which is lower than the low pressure lower limit of the pressure relay Exhaust pressure is too high, causing high-voltage relay action power off, oil pressure is too low, oil pressure relay action relay, motor overload, thermal relay action relay compressor suddenly shut down during operation Elimination method: check the cause, which is blocked pipeline The pipeline must be unblocked. If the system refrigerant is insufficient, check the cooling capacity of the condenser or the cooling air volume. Check the pipeline and oil pump of the oil delivery system Check if the power supply voltage is low or the cooling load is too large 2. Exhaust gas compression is too high The reasons for excessively high exhaust gas compression are: insufficient cooling water in the water-cooled condenser or insufficient cooling air in the air-cooled condenser The surface of the condenser tube cluster is too thick or too thick, causing difficulty in heat dissipation There is too much air refrigerant in the refrigeration system. The valve in the exhaust pipe is faulty, causing excessive pressure. Exhaust compression is too high. Elimination method: check whether the valve is fully open, increase the water supply, or check the motor voltage, speed, transmission belt Whether it is too loose to clean the scale, scrub the oil stains, make the surface of the condenser tube cluster clean, release the air, and discharge the excess refrigerant Check and correct the valve 3. The wet stroke of the compressor The causes of the wet stroke of the compressor are: the thermal expansion valve fails and the opening degree is too large (2) The solenoid valve fails, and a large amount of refrigerant enters the evaporative discharge pipe after being shut down, and enters the compressor system when the power is turned on again to inject too much refrigerant The thermal expansion valve's temperature-sensing package is loose and unbound, which causes the thermal expansion valve to open to increase the wet stroke of the compressor. Elimination method: close the liquid supply valve, repair the thermal expansion valve, repair the solenoid valve, and release excess refrigerant Check the tying of the thermocouple Fourth, the compressor is stuck The reasons for the compressor stuck: there are dirty impurities in the lubricating oil The oil pump's oil pipe is blocked, causing the cylinder to lack oil and the piston is stuck The handle pin of the oil pump main gear inserted into the crank is twisted, which causes the oil system to be cut off. The elimination method of the compressor is stuck: replace the new lubricating oil, repair the oil pump pipeline, replace the main gear shaft of the oil pump 5. There is abnormal noise in the cylinder The reasons for abnormal noise in the cylinder are: The gap between the dead point in the cylinder is too small, the gap between the piston pin and the connecting rod is too large, the valve disc is broken, the oil produced by the crankshaft or the connecting rod is splashed with oil, the sound is adjusted in the cylinder, the thickened cylinder gasket is replaced The piston pin or bushing is immediately shut down to replace the valve piece. It is not necessary to shut down for a short time, such as after a few minutes to shut down to check Six, there is sound in the crankcase The reason for the noise in the crankcase is: the connecting rod nut is loose, the gap between the connecting rod and the big head bearing is too large. 7. The compressor does not start up. The reasons why the compressor does not start up are: poor power supply fuse contact, blown starter's vertical contact point. Poor temperature controller out of adjustment or failure. The setting of the pressure relay is not suitable. The compressor does not start. Removal method: check the power supply, fuse, check the starter, wipe the contacts with gauze, check the temperature indication position, check each component, check each component of the pressure relay or set value 8. The insufficient cooling capacity of the compressor The reasons for the insufficient cooling capacity of the compressor are: the piston ring is worn or the gap between the piston and the cylinder is too large due to wear How to eliminate the insufficient cooling capacity of the compressor Replace the new piston ring or repair and replace the new parts Nine, the compressor and the motor coupling coupling noise There are reasons for the compressor and motor coupling coupling noise: The compressor and the motor coupling are not properly matched. The coupling key and keyway are not properly matched. The elastic ring of the coupling is loose or damaged. The inner hole of the coupling and the shaft are loose. The compressor and the motor coupling are noisy. elimination method According to the requirements of correct assembly, reassemble the adjustment key and keyway, replace the new key to tighten the elastic ring or replace the new part to adjust the tightening belt to adjust the tightening coupling.