I have noticed a strange problem with my 2009 Mazda5. On several long trips, stopping only for a few minutes for gas and rest stops, the air conditioner quits working after about five or six hours. If I turn the air conditioner off for about a half-hour and restart it, it works fine. This has happened consistently. Any idea what the trouble might be?
Most likely, your evaporator is freezing over. It could be due to a low R-134 level or sensor problem, or it could be a normal issue for your car in the right conditions.
You should be able to avoid the freeze up by setting the fan speed higher and/or setting the air inlet to recycle instead of fresh.
Thanks, I’ve had the air inlet on recycle but I will adjust the fan speed higher next time. I will also get the sensor checked out.