How to check the fault of the pipeline of the automobile refrigeration system?

Hello according to your description, the main test content from the catheter for damage and cracks; Whether the catheter plug is oily, loose, or leaking; Whether there is air leakage at the interface of the condenser, accumulator, reservoir dryer, compressor and evaporator unit. During the testing process, the corresponding tests are carried out with a special tool - a refrigerant leak detector. Hope mine is helpful to you, hope, thank you!!

Are you referring to pipeline leaks, generally the meter has a liquid level indicator, if there is a leak, it will be displayed.

Hello, which leak does this need to be checked?

The steps of checking and judging the fault cause of the refrigeration system can be summarized as listening, touching, seeing, and measuring, and then the fault of the system can be judged through comprehensive analysis.

1) Listening: Listen to user feedback; Listen to the air conditioner for abnormal noises.

or noise. 2) Touch: After the air conditioning system runs for a few minutes, touch the compressor shell and its inlet and exhaust ports to test whether the temperature is normal; Detect whether the temperature of the condenser, liquid storage filter drier and its inlet and outlet pipes and connecting pipes is abnormal, and whether there is a sudden change in temperature.

3) Look: Carefully check whether the connecting pipes of the refrigeration system are damaged and flattened; Check whether the pipe joints are firmly connected and whether there is any leakage of oil stains; Check whether there is frost or condensation in the connecting pipes, liquid storage filter driers, expansion valves, etc.; Observe whether there is any abnormality in the flow of refrigerant through the sight glass; Check whether the condenser heat sink is blocked by dirt; Check whether the air inlet filter is blocked by impurities, etc.

4) Measurement: With the help of manifold pressure gauge and other instruments, the corresponding parts of the system are detected according to the specific fault phenomenon, so as to find out the cause of the failure.

Based on the comprehensive analysis of the above situations and phenomena, we can roughly determine the fault of the refrigeration system, and then carry out maintenance and elimination operations.

5) When checking the fault of the refrigeration system, it should also be noted that because the refrigeration system pipeline is completely closed, when the fault is not accurately judged, the system pipeline should not be easily opened and dismantled, so as not to cause unnecessary loss of refrigerant and air, impurities and other substances into the refrigeration system, and expand the scope of the fault, which will bring trouble to the maintenance work.

The faults of the automobile air conditioning system are roughly the following categories: non-refrigeration fault, insufficient refrigeration fault, intermittent refrigeration fault and abnormal air outlet, which is mainly manifested in the abnormality of the refrigeration system, electrical system and mechanical components, and only by timely diagnosis and elimination of these faults can the normal operation of the system be guaranteed or maintained. The failure of the refrigeration system is often analyzed by the pressure inside the system, the refrigeration effect, and the refrigerant.

Leaks are also an important basis for analyzing accidents. Faults in the electrical system often manifest themselves in the form of electrical components.

Damage, fuse.

Burnout, poor contact of the binding post, etc., these faults are often accompanied by peculiar smell, overheating and other phenomena. Abnormalities in mechanical components are generally compressors, blowers, pulleys, electromagnetic clutches, and expansion valves.

Failure of shaft seals, bearings, valves, etc. In view of the common faults of the automotive air conditioning and refrigeration system, we can analyze the cause of the fault according to the working principle of the refrigeration system through the fault phenomenon, and quickly eliminate the fault, so as to ensure the normal operation of the air conditioning system.

Breakdowns that tend to occur are air conditioner failures, engine failures, starter failures, coolant failures, and engine failures that cannot be cooled.

Failure of air conditioning compressors, clutches, braking systems, belts, and cabin air filters is common.

Air conditioning compressors, condensers, evaporators, expansion valves, reservoir dryers, these parts are prone to problems.

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Hello, the high and low pressure maintenance valve, also known as the access port, is connected to the air conditioning pressure gauge and is used for the maintenance of air conditioning and refrigeration projects.

For example, refrigeration pressure check, refrigeration oil filling, refrigerant filling, and vacuum operation of the nucleus of the Li Extraction Plexus, etc., are helpful for seepage.

For refrigeration systems that use expansion valves, liquid return is closely related to improper sizing and use of expansion valves. The expansion valve is too large, the superheat setting is too small, the installation method of the temperature sensor pack is incorrect, the insulation bandaging is damaged, and the expansion valve is malfunctioning.

For small chains or cold systems that use capillaries, adding too much liquid can lead to guessing of the return.

When the evaporator is frosty and heavy, or when the fan fails, the heat transfer becomes poor, and the unevaporated liquid will cause the liquid to return.

04. Frequent fluctuations in the temperature of the cold storage will also cause the expansion valve to malfunction and cause liquid return. For refrigeration systems where liquid return is difficult to avoid, the installation of a gas-liquid separator and the use of evacuation shutdown (i.e., allowing the compressor to drain the liquid refrigerant from the evaporator before shutting down) control can effectively prevent or reduce the hazards of liquid return.