Q: My AC only blows hot air in my car. My car was idle for 30 min. Then the ac started blowing hot and then had a burning smell.

asked by on July 15, 2017

My AC started blowing hot air in my car. It does not get cool.

The problem started a few weeks ago. When idle, the ac will work just fine and eventually start to blow hot air. At this point, I would usually drive away the block, and the ac would start back blowing cool air. But unlike all the previous times, yesterday there was also a burning smell.

So yesterday, I sat in my car with it idle and the ac blowing for about 30 minutes. Initially, it blew cool/cold air and then get started to get hot. Almost immediately I started to smell a burning smell. As usual, I drove around the block to see if the ac will cool down. It didn't. Then I turn the car off for a while and tested the ac later and it does not get cool anymore. It only blows hot air.

Could it be the condenser fan, the compressor, or some leak? Please let me know what you think it could be and possible pricing for a repair. Thank you for your help.

My car has 200000 miles.
My car has an automatic transmission.

You should first verify the a/c system is full of refrigerant and then while running ac verify the compressor is turning on and engine cooling fan comes on also with it. If they do not then you may have a leak in the system or a bad compressor and leaked out the refrigerant. Have these checked and then if you need further diagnosis I suggest getting assistance with diagnosis from a mechanic like one from YourMechanic.

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