A/C not cold

[painlus]

Hi Guys.
My a/c stopped blowing cold air. Based on the FAQ's and searches, here's what I have found:
1. Based on the inspection while running the A/c system and engine on - the Glass window on that cylinder in front of the radiator is clear (so freon appears full)

2. There is no all-or-nothing issues with the climate control system (rules out circuit-breaker issue)

3. the compressor wheel rotates freely by hand with the engine off. (rules out seized compressor wheel)

4. all fuses relating to the a/c system (all 4) were normal.

Any ideas what this might be? Stuck evaporator valve?

Thanks for your help as always,

Greg

 

[painlus]

FYI - after a trip to Lynnwood acura ($219), turms out it was not low freon (you'd see bubbles), but NO freon. Refill and pressure check for 3 hours yielded no signs of leaks. If it doesn't leak, where did it go?

 

[ChrisK]

Did they check to see if it is leaking at the evaporator? I just did the 134a conversion today but mine has a small leak at the evaporator. That is under the dash and requires complete dash removal so I'm holding off on the repairs until it all leaks out again which in my case should be months hopefully. Anyway, i it is leaking at the evap it might not be easily detectable unless they specifically checked that area.

I checked my papar work and this is my diagnosis.

No visable leaks found. Found a slight leak from the drain hose that could mean a possible leak in the evap.

 

[Norm]

I had the same problem. When the evaporator coils is leaking it can be difficult to find, even with a dye. In my case the musty odor was the tell tale sign. I have had the coil replaced, and now, no missing freon, air is always cold and no more musty smell.

(And yes, when the coil was removed and tested, it was leaking.)

 

[painlus]

Yes the smell is musty - even more so then ever before. Can you access this from under the hood or do you need to access the coil from the inside?

Thanks for all you help folks!

Greg

 

[ChrisK]

Changing the evaporator is a big labor intensive job since it requires the removal of the entire dash. They practically have to take your entire interior out. I think they quoted me $1900 for the job if/when I need to do it.

 

[Larry Bastanza]

I do not see the point of investigating an evaporator leak when the system holds vacuum. You did not say what year your car was, or if based on your visit to the dealer is it blowing cold now??

Sounds to me like you are done for the short term. Drive your Cold car.

Over time these systems will just tend to leak ever so slightly. MY 1991 had .4 lb's of freon when evacuated. If was not cold, only slightly cool on one side. Same as you no leaks found, so it was converted to 134a and been blowing COLD ever since.

Also, make sure the drain tube is clear in the blower housing. (llok to see there is a puddle of water under the car after you run the A/C for a while and park it)

HTH,
LarryB

 

[ChrisK]

Over time these systems will just tend to leak ever so slightly. MY 1991 had .4 lb's of freon when evacuated. If was not cold, only slightly cool on one side. Same as you no leaks found, so it was converted to 134a and been blowing COLD ever since.


LarryB

This is exactly what I'm hoping on my system as well. I'm hoping my 134a will last a long time and if it does I probably will forgo the evap change. I figure they barely detected a leak on the drain tube so the leak if any could be really small. Right now my car is like a feezer

 

[NSXcellence]

Has anyone converted a '91 NSX to R34 air? What sort of price should I expect? And what's the difference 'twixt R34 and 134? Thanx.