AC should be working now, but...
scottswan
07-26-2005, 08:51 AM
...it's not. 2000 Cavalier 2.2 AC blows no cold.
We had most of the high pressure tubing replaced at Bell tire, it worked for about a day. Then purchased and had a guy install a rebuilt compressor and still have hot AC blowing.
The compressor does enguage when I hit the AC switch, and the fan turns on. The blower seems to work ok. I can hear valves changing when I adjust the air flow to different vents. The system just got recharged two days ago when they replaced the compressor so it should be good.
The compressor guy seemed to think there was something electrical wrong, but I don't know what else electrical there is to the AC system.
Engine turns the compressor when the clutch enguages, makes the R stuff cold and sends it to the evaporator where the blower fan blows the cold into the car. Am I missing anything?
Thx
-Scott
We had most of the high pressure tubing replaced at Bell tire, it worked for about a day. Then purchased and had a guy install a rebuilt compressor and still have hot AC blowing.
The compressor does enguage when I hit the AC switch, and the fan turns on. The blower seems to work ok. I can hear valves changing when I adjust the air flow to different vents. The system just got recharged two days ago when they replaced the compressor so it should be good.
The compressor guy seemed to think there was something electrical wrong, but I don't know what else electrical there is to the AC system.
Engine turns the compressor when the clutch enguages, makes the R stuff cold and sends it to the evaporator where the blower fan blows the cold into the car. Am I missing anything?
Thx
-Scott
scottswan
07-26-2005, 09:32 AM
Bell Tire Replaced the "lowside line" and "reciever drier", then recharged the oil and added a dye.
Then when taken back to them after the AC died again they estimated the compressor replacement, which was too high so we took it to an independant mechanic who R/R'd it with a rebuilt one.
Then when taken back to them after the AC died again they estimated the compressor replacement, which was too high so we took it to an independant mechanic who R/R'd it with a rebuilt one.
scottswan
07-26-2005, 02:32 PM
After a 2nd diagnosis it has been determined that the compressor clutch does NOT enguage. After some testing of the electrical system I found the connector on the compressor had a bent pin and was not making contact. Using an inspection mirror and some tiny 90° pliers I was able to correct that problem and it now runs if I override the pressure sensor.
To override the pressure sensor I used a potentiometer (20k multi-turn), soldered 3 wires to each leg and then tinned the other end of each wire.
The tinned end of the 20ga wires fits nicely in the 3 pin connector that was removed from the actual sensor. Using that I can force the compressor on and off by simply turning the pot.
Using a $9 AC pressure guage I determined that the low side system pressure was on the low end. I can smell some AC in the car but it's not very cold. Most likely the compressor guy charged the system without the compressor running so thats why it is now low.
I purchased a recharge kit (single hose type), one can of R134a refrigerant and one can of R134a Ester Oil charge. After reading all the stuff I am still confused as to the difference between the oil and the refrigerant. I don't want to over fill, and I'm assuming the guy did put in the oil, so I'm planning to only charge with the refrigerant (unless somebody replies here, but I'm starting to doubt that).
Thats the latest. This is turning into more of my own personal blog of AC repair 101 ;-)
To override the pressure sensor I used a potentiometer (20k multi-turn), soldered 3 wires to each leg and then tinned the other end of each wire.
The tinned end of the 20ga wires fits nicely in the 3 pin connector that was removed from the actual sensor. Using that I can force the compressor on and off by simply turning the pot.
Using a $9 AC pressure guage I determined that the low side system pressure was on the low end. I can smell some AC in the car but it's not very cold. Most likely the compressor guy charged the system without the compressor running so thats why it is now low.
I purchased a recharge kit (single hose type), one can of R134a refrigerant and one can of R134a Ester Oil charge. After reading all the stuff I am still confused as to the difference between the oil and the refrigerant. I don't want to over fill, and I'm assuming the guy did put in the oil, so I'm planning to only charge with the refrigerant (unless somebody replies here, but I'm starting to doubt that).
Thats the latest. This is turning into more of my own personal blog of AC repair 101 ;-)
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