What are the symptoms of a clogged car air conditioning dryer?
2 Answers
In the case of a clogged car air conditioning expansion valve, the gauge shows high pressure on the high side and low pressure on the low side; if the dryer is clogged, the gauge shows low pressure on both the high and low sides, with high temperature before the clog. A mnemonic for diagnosis: Low pressure high and high pressure low, replace the compressor; both pressures high, need to vent or there's a cooling issue; gauge fluctuating indicates moisture in the system, evacuation must be more thorough; both pressures low indicate a lack of refrigerant, otherwise there's a blockage in the system. The functions of the car dryer are as follows: 1. Storage function: It stores and supplies liquid refrigerant in the refrigeration system to compensate and regulate the surplus or shortage of liquid refrigerant when operating conditions change. Generally, when the air conditioning system starts, the load is large, requiring a high circulation of refrigerant. After operating for a while, the load decreases, and the required refrigerant quantity reduces accordingly. 2. Filtration function: Although all components in the refrigeration system should be strictly cleaned and dried before leaving the factory, dirt may be inadvertently introduced during installation, or contaminants like oxide scales may form in the pipes. The refrigerant itself may not be perfectly clean, and powder and wear debris from the compressor operation can also be present. The filter removes these mechanical impurities and dirt to ensure smooth refrigerant flow and prevent blockages that could affect normal operation. 3. Drying function: It absorbs moisture in the refrigerant. Moisture can come from inadequate drying of the refrigeration system, air ingress, or dissolved water in the refrigerant. The presence of moisture can cause "water blockage." In the air conditioning refrigeration system, the dryer filter's role is to absorb moisture in the system, block impurities to prevent them from passing through, and avoid ice and dirt blockages in the refrigeration system pipes.
Last time I was driving, the air conditioning suddenly stopped cooling, and the previously cool breeze turned hot, with the compressor making a loud buzzing noise. The mechanic said the dryer was clogged, which can block the refrigerant, causing pressure to spike and the AC to essentially 'go on strike.' If left unrepaired for too long, the compressor could burn out, leading to costly repairs. That time on the highway, I was sweating profusely, and it even became a safety hazard. It's recommended to check the dryer during regular maintenance—dust or debris buildup can easily cause clogs. Replacing it early can prevent AC failure, making summer drives more comfortable. Remember, if you notice the AC air isn’t cold, get it checked by a professional shop right away. Don’t tough it out—small issues can turn into expensive problems if ignored.
