Air conit/2002 buick rendezvous

Take to a shop that has the proper gauges and ability to vacuum the system properly. Do not simply try and add Freon as it only causes an air gap and false readings. In addition, some cars require a resetting of values on the cars computer brain in order to function properly.

You may well have a ccot system. Cycling Clutch Orifice Tube. Rather than having a adjustable expansion valve, they use a fixed orifice for an expansion valve, then turn the compressor on and off to maintain correct pressures. This does produce higher fuel mileage. It is not necessary to run the compressor full time to achieve proper cooling.

check compressor clutch clicking in when you turn on and off or belt tight enough

If you have the ac turned off the clutch on the front of the compressor should disengage. Then the ac pulley will spin freely and you can drive until you save up for a new compressor. You may want to save up they are about 3 to 400 bucks plus installation which is about 300.

The squeeling is the belt because the air compresor is likely seizing. At idle it can't turn the compressor, in motionthe compressor probably turns and cools the air. Most air conditioners come on when the defroster is on.

Hi, the thermostatic expansion valve or txv is the metering device located in the liquid line. Its job is to meter refrigerant ( freon ) into the evaporator coil that is sealed by your fire wall and cools the auto down. This auto doesn't have the orifice tube that refrigerators use!! This txv would have to be plugged up at the screen to not meter freon into the system. I doubt its the txvalve. What I would do, is determine if the compressor is running and pumping freon through the system. You say it has a full charge, how was the determined? The compressor would have to be running. Its a pump under the hood that your serpentine belt goes around, and has what is called a clutch plate on the front of it. With the engine running, you can have someone set in the seat while you look under the hood. This pump has 2 aluminum lines coming out of it and the belt is on it also. Have the driver turn the a/c on cool high and you listen and look at the belt on top.It will be turning with the engine running and as soon as the a/c is turned on, you will hear this clutch engage on the front of the compressor, and loud click as this clutch will also start to turn. If it doesn't turn, the compressor is not working due to maybe a blown fuse, no freon and its off on its low pressure switch. If you know the compressor works for sure and the clutch is engaged, then you may have a problem in the expansion valve. Drop by a shop, go by auto-zone and have one of the guys look at the compressor and tell you if the clutch is engaging. You need to find this out. If its not, the fuse that's located in the electrical box under hood, its marked, will have a 30 amp fuse in it. I would personally drop by a auto shop and just ask them to tell you if the compressor and clutch is engaged when you turn it on. This would be the best thing to do, and then go from there. If its working and blowing hot air, you do have a internal problem and it will need service. You can't do this on your own, it takes special training and equipment to check. Consentrate on the compressor first and let me know what you find out. We can go from there, and figure this problem out. This a/c is new. Please keep me posted on this.
Sincerely,
Shastalaker7
A/C, Heating, & Refrigeration Contractor

Either have the Freon level checked or check it yourself. YO can get a refill kit or can from almost any place that sells Engine Oil and Filters. Walmart carries them as well. The can will have a connector hose and gauge on it.

I had to do that once, but it was on an older vehicle that AC was optional. Probably your best bet would be to see if you can wrap the belt on there, but bypass the AC pump. Then just mark the belt with a white marker to get the length you need. Take it to the parts store and have them measure it with their guide. They should be able to find you one that length. If a Rendezvous came without AC, you could just go in and ask for the belt for one without AC, but I don't think they did.

either the freon charge is about 1/3 low, or the expansion valve needs to be replaced. Freon is getting into the evaporator, but not in great enough volume to cool the air unless it is coming in cool to start with. check your ac charge, and if it is full, then have it emptied, change out the expansion valve, and recharge it

Yes the system can be full of freon and yet not work, the pressure switch could faulty, the expansion valve too could be faulty, he drier receiver too.
On switching 'on' the AC , is the AC compressor workingor rather does it engage?
The AC compressor clutch too could be not functioning.
I guess you have to go step by step to check first if the AC compressor does rotate on switching 'on' the AC.