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Intermittent AC Long Distance

2009 Civic has an intermittent ac during long distance trips. About 1hour into a trip it feels warm I turn the blower up higher. I can turn it to the highest setting and it sounds like it’s blowing at full blast but no air is coming out at all. I turn the ac off completely for 45 mins to an hour to “thaw” then it comes back on. Dealer had it 6 times now only once they were able to replicate the problem. The blower motor, expansion valve & termistor have been replaced.

Unless it is under warranty, I would recommend finding a local INDEPENDENT (Not a chain outfit) A/C or Radiator shop. They generally are far more experienced and in the long run cheaper and better.

If you had a hart attack, you would not ask your general doctor take care of you, so likewise with your car.  It will likely be cheaper and better in the long run.

Good Luck

I have been told that if am AC unit is low on freon, it can actually freeze up. I’m not sure of the science around it, but I have heard it a few times. Has anyone but an actual gauge set on the car??

@gsragtop I work in HVAC and I know that is true in that instance. They have performed a leak search on it but no leaks were found. The dealership thought it may have had moisture in the system so they pulled a deep vac on it but it’s still having the issue.

@josephemeehan I bought the extended warranty but it seems like people on other boards are recommending finding an independent AC shop too.

Thanks for the input

You need to familiarize yourself with the compressor when it is running and when it is not so that you can tell the difference. Then when this happens, you can stop, open the hood and see if the compressor is running. If it is not, then there is a self protection circuit at work here. If it is, then the evaporator is probably icing up.