What are the symptoms of a clogged expansion valve?

[LaEva]

When an expansion valve becomes clogged, the air conditioning system may exhibit symptoms such as poor cooling performance, icing of the expansion valve, noisy compressor operation, and abnormal refrigeration. The expansion valve plays a throttling role in the air conditioning system. During operation, it regulates the refrigerant flow and system pressure by controlling the opening degree of the expansion valve to ensure normal system functioning. Causes of thermal expansion valve clogging: Clogging faults in the thermal expansion valve of the refrigeration system often occur, including "dirt clogging" and "ice clogging." The main cause of dirt clogging is the presence of impurities in the system, such as welding slag, copper chips, iron filings, fibers, etc. Ice clogging occurs due to excessive moisture (humidity) in the system. Sources of moisture include: (1) Insufficient vacuuming time during installation, failing to remove all moisture from the pipelines, and poor welding at pipeline connections, leading to air leaks. (2) Failure to purge the air from the connecting hoses when charging the system with refrigerant. (3) Introduction of air when adding lubricating oil to the system.