My A/C compressor was replaced a month ago and it performs like a dream in the city, but today while traveling from Laredo, TX to San Antonio TX the lines A/C was so cold and the vents suddenly stopped blowing air, even If I changed my fan selector to the highest position they didn't blow air, just a little breeze, so cold but not so much amount of blowing air, then I made a stop at a gas station and noted that the low pressure line was covered in ice ! The lines are freezing when traveling in the highway, what could be the problem ? When the low pressure lines evaporate the ice (engine off) the fan returns to it's normal status and blows the normal amount of air expected to exit through the vents. What can I do ?

 

By the way my car is a '96 Infiniti I30

 

Maybe they over filled it with R-134. I heard when it is over filled the compressor will shut off to keep it from damage.

 

If it's super-humid out this can happen. I froze the vents several times down in New Orleans in another car. My Max never gets cold enough though....

-RMB

 

Yes rmb, was so humid while I was traveling down the road to San Antonio, may be I just need to wait to take a trip with a HOT Summer temp of 45 degrees (Very usual in TX) to see if it will not freeze the A/C lines again.

Thanks

 

Your compressor may not be cycling on and off as it is supposed to. If it runs constantly, the lines will freze. I had this happen to me several years ago in a Volkswagen. The fix was to replace a temperature sensor or relay, I can't remember exactly.

 

The maxima (and I'm therefore assuming the Infiniti) compressor does not cycle (unless there's a problem). Sounds like your air conditioner is working a bit too well, and the water that condenses on the evaporator is freezing up. You can melt it by setting the controls to lowest cooling and putting the fan on full blast.
The guys at aircondition.com are a good source of help.