In the dead of summer, the last thing any driver wants to experience is AC failure. When automotive AC systems fail, they often fail during periods of intense work during the summer or after neglect during the winter. If your car's AC system stopped working recently, the failure point is likely to be located in the compressor, condenser, or blower fan. A qualified automotive mechanic can help you diagnose the root cause of the issue and find a replacement part. If you want to look into the problem yourself before taking your car into a shop, here are the three most important parts to look at.
Without a compressor, automotive AC units simply wouldn't be able to cool hot air efficiently enough for it to be noticeable. As refrigerant flows through the AC system, the compressor changes it from a low-pressure liquid to a high-pressure gas. During this process, the refrigerant pulls heat into itself to make the change in its physical state. Compressors work by forcing liquid coolant into a small space that leads out into AC lines and, eventually, the condenser. When compressors fail, they either aren't able to hold pressure or their interior components can't move freely. If you turn on your car's AC and the system only blows hot air, a faulty compressor could be the problem.
Your car's condenser takes super-heated refrigerant from the compressor and pulls heat from it through highly conductive metal tubing. The refrigerant then turns back into a cool liquid that cools the air that comes out of your vents. Condensers are relatively simple AC components that look and function much like car radiators, so when they fail, they usually break and leak. Sometimes, these leaks are visible and obvious. Other times, they leak internally, disrupting the flow of refrigerant. If your AC works well just after being recharged with fresh refrigerant but slowly fails again, your condenser could be the problem.
One of the easiest-to-diagnose AC problems is a failed blower fan. If your blower fan fails, the cool air produced by your AC system won't be able to reach the interior of your vehicle. Blower fans typically have ball bearings that make them spin smoothly and quietly. If these bearings crack or the lubricant around them becomes sludgy, they can stop spinning. Without a functional blower fan, no air will come out of your vents when you turn on your AC system. Some professionals may be able to replace the bearings in blower fans, but most of them will recommend a blower fan replacement instead.
To learn more about auto AC repairs, contact an automotive mechanic in your area.