Common faults and troubleshooting methods of refrigeration compressors

Common faults and troubleshooting methods of refrigeration compressors

The compressor is the "heart" of the refrigeration system. The compressor 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 the high-temperature and high-pressure refrigerant gas to the exhaust pipe to provide power for the refrigeration cycle, thereby realizing the refrigeration cycle. The editor summarizes the common faults and troubleshooting methods of the compressor to help you better maintain the compressor.

is air in the refrigeration system;

　　 (4) Overfilling of refrigerant;

　　 (5) The valve in the exhaust pipe fails, causing the pressure to be too high;

elimination method:

　　 (1) Check whether the valve is fully open, increase the water supply, or check the motor voltage, speed, and the transmission belt are too loose;

　　 (2) Clean the scale, brush the oil, and make the surface of the condenser tube cluster clean;

　　 (3) Let go of the air;

　　 (4) Exhaust excess refrigerant;

　　 (5) Check and correct the valve;

3. Cause the wet stroke of the compressor:

　　The reasons are:

　　 (1) The thermal expansion valve fails and the opening is too large;

　　 (2) The solenoid valve fails, a large amount of refrigerant enters the evaporator pipe after shutdown, and enters the compressor when it is turned on again;

　　 (3) The system is filled with too much refrigerant;

　　 (4) The temperature sensing bulb of the thermal expansion valve is loose and not tied, causing the opening of the thermal expansion valve to increase;

elimination method:

　　 (1) Close the liquid supply valve and overhaul the thermal expansion valve;

　　 (2) Overhaul the solenoid valve;

　　 (3) Release excess refrigerant;

　　 (4) Check the binding of the temperature sensing bag;

4. The compressor is stuck:

　　The reasons are:

　　 (1) Dirty impurities in the lubricating oil;

　　 (2) The oil pipe of the oil pump is blocked, causing the cylinder to run out of oil and the piston is stuck;

　　 (3) The shank pin of the main gear of the oil pump inserted into the crank is twisted, causing the oil system to cut off;

elimination method:

　　 (1) Replace with new lubricant;

　　 (2) Check and repair the oil pump pipeline;

　　 (3) Repair and replace the main gear shaft of the oil pump;

5. There is abnormal sound in the cylinder:

　　The reasons are:

　　 (1) The dead center clearance in the cylinder is too small;

　　 (2) The clearance between the piston pin and the connecting rod bushing is too large;

　　 (3) The valve plate is broken;

　　 (4) The sound of oil slamming caused by the crankshaft crank or the big end of the connecting rod;

elimination method:

　　 (1) Adjust the thickened cylinder gasket;

　　 (2) Replace the piston pin or bushing;

　　 (3) Stop immediately to replace the valve;

　　 (4) There is no need to shut down for a short time, such as stopping for inspection after a few minutes;

6. There is sound in the crankcase

　　The reasons are:

　　 (1) The connecting rod nut is loose;

　　 (2) The gap between the connecting rod and the bearing bush is too large;

elimination method:

　　 (1) Stop and re-tighten;

　　 (2) Replace the tiles;

7. The compressor can't start:

　　The reasons are:

　　 (1) Poor contact and blowout of the fuse when the power is cut off;

　　 (2) Poor contact of the vertical contact point of the starter;

　　 (3) The temperature controller is out of adjustment or malfunctions;

　　 (4) The adjustment of the pressure relay is not suitable;

elimination method:

　　 (1) Check the power supply and fuse;

　　 (2) Check the starter and clean the contacts with gauze;

　　 (3) Check the temperature indication position and check all components;

　　 (4) Check each component or setting value of the pressure relay;

8. Insufficient cooling capacity of the compressor:

　　The reasons are:

　　 (1) The piston ring is worn or the gap between the piston and the cylinder is too large due to wear;

elimination method:

　　 (1) Replace with new piston ring or overhaul with new parts;

9. There is noise in the compressor and motor coupling:

　　The reasons are:

　　 (1) The compressor and the motor coupling are not properly matched;

　　 (2) The key and the keyway of the coupling are not properly matched;

　　 (3) The elastic ring of the coupling is loose or damaged;

　　 (4) The belt is too loose;

　　 (5) The inner hole of the coupling and the shaft fit loosely;

elimination method:

　　 (1) Reassemble according to the correct assembly requirements;

　　 (2) Adjust the fit of the key and the keyway, replace the key;

　　 (3) Fasten the elastic ring or replace it with a new one;

　　 (4) Adjust and tighten the belt;

　　 (5) Adjust and tighten the coupling;