Accumulator covered entirely in frost without A/C running

[Mike534x]

So this just happened minutes ago. Drove to the store, so about a 30 min trip. I ran the A/C yesterday, got in today and shut it off since its nice out. Pulled back into the drive way and popped the hood open to top off washer fluid and oil.....annnddd I see this.

So the accumulator is covered in a massive amount of frost, and all connections leading down to the passenger side firewall are covered as well. I have never seen anything like this at all. I had A/C work done earlier in the summer, the front condenser was replaced due to a bad leak.

 

[littleblazer]

So this just happened minutes ago. Drove to the store, so about a 30 min trip. I ran the A/C yesterday, got in today and shut it off since its nice out. Pulled back into the drive way and popped the hood open to top off washer fluid and oil.....annnddd I see this.

So the accumulator is covered in a massive amount of frost, and all connections leading down to the passenger side firewall are covered as well. I have never seen anything like this at all. I had A/C work done earlier in the summer, the front condenser was replaced due to a bad leak.

Mine does that all the time while running, even the front crossover tube on top of the valve cover too.

Do you have manual controls or automatic?

 

[Mike534x]

Automatic controls. I had the A/C off, and usually when it is running it just gets a very light frosting.

 

[littleblazer]

On my truck, even if I shut off the a/c but leave the blower on... if I turn the car off and then start it back up later the A/C usually comes back on for whatever reason. The envoy and escalade did this.

 

[Mooseman]

And some have reported that even with the A/C off, the compressor still engaged. I said it was a conspiracy to wear out parts faster. To counter this, I usually pull the low pressure switch plug or the compressor relay during winter months.

 

[TollKeeper]

The Mercury I had did this, but my Envoy with Auto Climate, didnt.

 

[littleblazer]

And some have reported that even with the A/C off, the compressor still engaged. I said it was a conspiracy to wear out parts faster. To counter this, I usually pull the low pressure switch plug or the compressor relay during winter months.

I run my A/C in the winter! (no joke, I actually got it to snow inside the trailblazer on a damp winter day) if recirculate is on the compressor cycles so that humidity doesn't build up inside the car in the winter. If you have A/C off and recirculate off the only time it comes on is with defrost... for the same reason.

 

[mrrsm]

Mike... Even though this involves a different GM Vehicle... The Symptoms and Thermodynamics are right on the money for this Video hitting pretty close to the mark on the simple repair and Component R&R that will quite likely solve this problem:

Using an edited cut-out of your own image, I highlighted a Yellow/Red Oval around what appears to be the very same switch described in the attached Video. THAT things is the probable culprit in your present situation.

 

[Mike534x]

Small update;

I replaced the low pressure switch per the video @MRRSM linked, and it seems like the issue has been solved (keeping fingers crossed). So far I haven't had a thick covering of frost on the accumulator. I'd have to say my A/C is working a bit better then it was before! I had another small problem that seemed to have been fixed as well, and that was my A/C blowing cold, to luke warm, back to cool again while sitting at idle or at a stop light. Now it just drops to cool and gets cold as soon as you start driving. So I guess it was a kill two birds with one stop type of deal. I wouldn't have thought the switch was the issue.