What are the symptoms of excessive pressure in a car's air conditioning system?

[JaceDella]

There are two symptoms of excessive pressure in a car's air conditioning system: first, the cooling effect of the air conditioner deteriorates; second, the increased working pressure of the compressor causes it to overheat, leading to intermittent operation or complete failure. Excessive refrigerant: Release some or all of the refrigerant and then refill it. Excessive air conditioning oil: Release all the refrigerant, use a machine to extract the excess oil, and then refill the refrigerant. Poor heat dissipation in the air conditioning condenser: Clean the surface stains and the condenser pipes, and check the cooling fan to see if it operates at high speed. The opening of the air conditioning expansion valve or expansion tube is too small: Replace the expansion valve or expansion tube, thoroughly clean the air conditioning pipes, and replace the dryer if present.