Hey guys,

I have a 2000 expy and i have 47000 miles on it. The AC stopped blowing cold air about a week ago, but the rear ac worked well, It blew colder than front. well yesterday the rear stopped blowing cold air also. i had the system checked when i was in florida last spring and they did not find any problems. also for about a year now when i am running the rear ac i can heard a faint squelling coming from where the compressor is. but now it is much louder. and i can heard it all the time now, weather the rear hvac controls are on or off.

Any Help before it goes to the dealer?

 

Thanks for the effort guys!!

 

Sorry, saw this the other day, but had to think about it for a while. I'm guessing it's a problem with the proportioning valve that sends refrigerant to the two a/c systems (front/rear). At least I think it has a proportioning valve. I only mention this because I had several refers that used one compressor to cool down more than one component and they all had something called a proportioning valve. When one component failed and it wasn't that component's thermostat, it was always a problem with the proportioning valve.

The squeeling is probably caused by an overloaded compressor. You see, if the valve is faulty, high pressure refrigerant is blocked to both systems. If it's blockd to one, it's like running just the front a/c, so there shouldn't be any sound. Now, if both systems are blocked, that creates an abnormally hign pressure and might be overloading the compressor and the belt is having a hard time dealing with it.

 

Dennis,

Thank you for the responce. I can totally see what you are talking about. would the proportioning valve cause the entire system to take a dump or is that another issue? also since my truck is off warrenty do you think this will be a expensive fix. i am toying with the idea of waiting till december to get this fixed at my dealer back home in Buffalo. it is the lack of transportation that keps me from getting it taken care of here in Montana.

 

I have no idea how much time or dollars it would take to repair your problem.

The tech would have to diagnose the actual problem first, evacute the system, change the part, then recharge and test the system. It's not going to be cheap, but it will certainly be less than it would cost to replace something like a bad compressor.

I've been giving this a bit more thought and I'm having some questions about my previous post. It's kind of wierd that the front would fail to cool while the rear is still working considering that the rear won't work unless the front is on first.

I know in the Navigator, you can make the front warmer than the rear and vice versa. Is it the same with the Expy? I'm beginning to wonder if it's a problem with some control circuit.

 

there is no type of proportioning valve on these. The lines are just Y'ed off to the rear. The reason the front could have quit first is because the difference in size of the orfice tube, or the compressor may be coming apart and its clogged the front orfice first, theres too many possibilities to guess on it from here. Just get it checked out , we see it every day.

 

Oh no a dreaded trip to "DEALERSHIP LAND" a place where anything is possible.. Especailly when it comes to HVAC.. Get ready for trail and error...

 

well bring it to kinston, north carolina because this dealershipland here doesnt do trial and error. In fact, letting people on here that cant even see or touch your truck tell you how to fix it is trial and error.
By the way, there is no compressor in the rear, the compressor on the engine runs both front and rear ac.