How to Check the Air Conditioning Pressure Gauge in a Sedan?
2 Answers
The method to check the air conditioning pressure gauge in a sedan is as follows: The pressure gauge has numbers, and you can read them directly. Specific steps: Start the engine, adjust the engine speed to approximately 1250 rpm, then turn on the air conditioning, set it to the coldest setting, and adjust the fan speed to maximum. Let it run for about 5 to 10 minutes until the engine temperature normalizes, and then perform the inspection. The sedan air conditioning system is a device that artificially regulates and controls the temperature, humidity, airflow velocity, and other parameters of the air environment inside a building or structure. The structure of the air conditioning system includes components such as the compressor, condenser, evaporator, four-way valve, one-way valve, and capillary tube assembly.
I've been repairing cars for over a decade, and checking a car's AC pressure gauge is quite simple. First, start the engine and turn the AC to maximum cooling at the lowest temperature, waiting a few minutes for the system to operate. Then locate the service ports in the engine bay: the low-pressure port is usually a thick blue tube, and the high-pressure port is a thin red tube. Connect the pressure gauge tool—blue to low pressure and red to high pressure. The gauge has two needles; normal low-pressure readings should be between 25-40 PSI, while high pressure should be between 200-250 PSI. Note that weather affects readings—in summer, high pressure may approach 250. If readings are too low, refrigerant may be low; if too high, there could be a blockage or compressor issue. Safety is crucial—avoid touching hot pipes, as refrigerant leaks are toxic and can cause frostbite, so wearing gloves is recommended. Regular checks can prevent AC failures and save on repair costs.