Q: A/c blowing cold air intermittently with warm air

asked by on May 13, 2016

My car has around 158,000 miles.The air conditioner blows both cool and warm air. What is causing this and what is the solution. Thanks.

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Hello. If the system continually blows hot and then cold, this is typically caused by a failing blend door actuator. If it fails, it can allow the temperature door to not hold the right position. It can also be caused by a bad metering valve or a compressor issue.

I typically start by checking the pressures in the AC system just to make sure that the system is functioning as it should. If it is, then I move to the doors under the dash to see if it is one of them not working properly, or if it is a failure in the control unit. If you need to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your AC system and perform any services that are needed.

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