Why is the High-Pressure Pipe of the Car Air Conditioning Not Hot?
2 Answers
Reasons why the high-pressure pipe of the car air conditioning is not hot: 1. Insufficient refrigerant in the air conditioning system; 2. Excessive opening of the expansion valve; 3. The compressor is not working or has malfunctioned. The car air conditioning system mainly consists of the compressor, expansion valve, high-pressure pipeline, low-pressure pipeline, evaporator, evaporator temperature sensor, and refrigerant. Working principle of the car air conditioning: Press the AC switch, turn on the fan switch, and the air conditioning enters the working state. First, the compressor compresses the refrigerant into a high-temperature and high-pressure liquid, which then dissipates heat through the air conditioning radiator to become a medium-temperature and low-pressure liquid. After being throttled by the expansion valve, it turns into a low-temperature and low-pressure gas.
There are several common reasons why the high-pressure pipe of a car's air conditioning system may not get hot. Having driven for many years, I've encountered similar situations, mostly due to issues with the AC system. The most common cause is insufficient refrigerant, which prevents the compressor from compressing properly, resulting in the high-pressure pipe not heating up. The compressor itself might also be faulty, such as internal valve sticking or belt loosening. Another possibility is a clogged expansion valve, obstructing refrigerant flow. A dirty condenser with poor heat dissipation can also affect overall performance. Or, there might be a leak in the pipeline, allowing air to mix into the system. If the AC cooling is poor in summer, it's essential to get it checked immediately, otherwise, the car interior can become uncomfortably stuffy. I recommend first going to a professional shop to check the refrigerant level and perform a pressure test, avoiding any haphazard disassembly that could worsen the situation. Regular maintenance, such as timely replacement of the AC filter and inspection of the pipelines, can prevent many issues.
