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Q: A/C blows warm air

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Our summer temperatures are over 100 degrees every day! I purchased my used car from the original owner and I’m not aware of the car’s situation/maintenance before I purchased it. The A/C progressively has been blowing warmer and warmer air. So I serviced it and it’s blowing ice cold again. I was told by the tech that the compressor is going bad. After service, as car was sitting in the sun and the a/c was blowing nicely cold, then he hit the gas, revved the engine and it blows Ice Cold. Revving it doesn’t make the electric fan spin any faster. I do spend a lot of time at idle and need it to be cold in that situation, for example while waiting for school to let out, with another child sleeping in back seat. When we get to driving again, it does get cooler, but I’m thinking that’s just due to the higher airflow through the condensor, not a weak compressor? Do you think it’s a bad compressor?

Hello. It sounds like you may have a weak compressor. The compressor is a pump for the A/C system and when it gets weak, it does not pump as well as it should. When this happens the air won’t be as cold at idle because the compressor is weak. When you increase the idle the compressor is forced to work harder and the air will be cooler. Before the A/C compressor is replaced I would have the A/C system inspected to make sure it is operating properly.

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