Is the thick or thin car air conditioning pipe the high-pressure one?
3 Answers
The thin car air conditioning pipe is the high-pressure pipe, while the thick one is the low-pressure pipe. Below are other methods to distinguish them: 1. High-pressure: Another way to distinguish is that the compressor to the condenser and the condenser to the evaporator box are all high-pressure. 2. Low-pressure: From the evaporator box to the compressor is low-pressure. Below are the steps to replace the air filter: 1. Choose the filter: Select the appropriate filter. 2. Unpack the filter: Open the new filter packaging and check if it is intact and undamaged. 3. Remove the filter: Remove the original car filter. 4. Take off the felt pad: Remove the felt pad covering the air outlet. 5. Open the cover: After removing the felt pad, you will see the rectangular cover of the air filter. Pull the cover to the right to open it. 6. Replace the filter: Take out the old filter and replace it with the new one.
Speaking of automotive AC line issues, I've encountered quite a few similar cases during my years as a mechanic. Typically, there are two main pipes in an AC system - one thick and one thin. That thick pipe is actually the low-pressure line, while the thin one is the high-pressure line. The high-pressure line is thinner because it carries high-pressure liquid refrigerant which has higher density and faster flow rate, making a thick pipe unnecessary. The low-pressure line is wider as it carries low-pressure gaseous refrigerant with lower density and slower flow, requiring more space for smooth gas movement. During repairs, if you accidentally mix them up - like connecting to the wrong valve when recharging refrigerant - it may cause leaks or even compressor damage. I recommend car owners regularly inspect AC lines, especially before summer, taking time to check connection seals to avoid breakdowns in sweltering heat. For DIY work, stick to low-side refrigerant charging only - high-side operations are dangerous and best left to professionals. Quick identification tip: The thick pipe usually runs from condenser to receiver-drier, while the thin pipe connects compressor directly to expansion valve. Remembering this detail can save you significant repair costs.
As a long-haul truck driver with years of experience, I've naturally learned a thing or two about air conditioning through frequent use. The thick pipe is the low-pressure line, while the thin one is the high-pressure line – this design is standardized across most vehicles. The high-pressure thin pipe carries high-pressure liquid refrigerant, which flows quickly and thus doesn't require much space; the low-pressure thick pipe handles low-pressure gas, which has a larger volume and needs more room. When the AC suddenly stops cooling while driving, it's usually a piping issue. My first troubleshooting steps are: feeling the pipe temperatures (the high-pressure pipe is typically hot to the touch, while the low-pressure pipe stays cool), then checking for oil stains or damage (the thin high-pressure pipe is more prone to wear from road vibrations). To save money and avoid headaches, I make it a habit to have a technician perform AC maintenance every two seasons – cleaning dust, recharging refrigerant, and ensuring seals to prevent leaks. AC failure during summer highway driving is particularly unbearable. Learning these basics helps identify problems promptly, reducing on-road troubles and safety risks. Simply put, the vehicle AC operates on a refrigerant cycle: compression on the high-pressure side, expansion on the low-pressure side, with pipe designs optimized for both efficiency and safety balance.
