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Q: What could be causing my AC to intermittently blow hot air?

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My AC suddenly started to blow hot air while driving yesterday. It would work fine as I was driving, but if I was stopped at a stop light for any length of time, it would start to blow hot air as soon as I started driving again. I replaced my battery and serpentine belt 4 years ago, and my cabin filter was replaced a year ago. Would any of these be linked to the AC acting up?

My car has 50075 miles.

The most common problem for this is usually a cooling fan that is not coming on with the A/C. Another possibility is that the A/C is low on refrigerant and may have a leak at the compressor or lines to the compressor.

I recommend having the A/C diagnosed to test for any of these problems and go from there. The A/C filter only filters out dirt like a house air filter does. Not changing it will reduce air flow but not change the temperature.

The battery and belts would not be at fault unless they are bad again, you should have them checked when you have the A/C pressures looked at, just to be sure.

I’d recommend getting some help from a certified technician for this job. They will be able to perform the necessary checks to diagnose your A/C issue and fix it accordingly.

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