Failing A/C compressor

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My mother's A/C stopped working on her 2001 Jetta TDI. I took the car into an air conditioning shop who diagnosed a bad compressor. The compressor still engages but doesn't build up enough pressure to function. The shop indicated replacing compressor, condenser and expansion valve. Is it really needed to replace all those parts if compressor has not failed completely yet?
 
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Not to mention whether buying a new or reman compressor, not replacing those parts will void the warranty of the compressor.
 
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USA
This is the SD7V16 variable displacement compressor. Sometimes the failure is only the control valve being stuck at zero causing it to spin but not pump. The control valve can be replaced separate from the whole compressor but the refrigerant must be removed first. Especially considering it is 20 years old the receiver drier should be replaced any time the system is opened.
 
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1,526
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TX, USA
Yes, for the new AC system since 1994, the condenser passage are very small and it cannot be flushed anymore. That is what I have read why the condenser have to be replaced. They also need to replace the Accumulator in addition to the above suggestion. Apparently the accumulator have to be replaced everytime the AC is opened. Now, it may be part of the new condenser so that is why they did not mention it.
 
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It's common for a AC compressor to leave a bunch of debris in the AC system when it fails, so shops will insist on replacing the condenser and expansion valve to not let that debris cycle back into the new compressor and damage the seals. Also an orifice tube does that same job as an expansion valve, so if you have an expansion valve you don't have a orifice tube.
 
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OK
I can't see the harm in replacing everything worth replacing after 19 years, unless the budget is so tight that the job has to be done in a sub-optimal way.
 
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Apple Valley, California
Originally Posted by mk378
This is the SD7V16 variable displacement compressor. Sometimes the failure is only the control valve being stuck at zero causing it to spin but not pump. The control valve can be replaced separate from the whole compressor but the refrigerant must be removed first. Especially considering it is 20 years old the receiver drier should be replaced any time the system is opened.
I though that too but I looked at the compressor and it does not have that valve that I could see
 
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Canada
Thread starter
Originally Posted by mk378
This is the SD7V16 variable displacement compressor. Sometimes the failure is only the control valve being stuck at zero causing it to spin but not pump. The control valve can be replaced separate from the whole compressor but the refrigerant must be removed first. Especially considering it is 20 years old the receiver drier should be replaced any time the system is opened.
I read about this variable compressor and the control valve, but looks like it might not have one. If the compressor is truly done for, looking like only way to do it is by also replacing the condenser and expansion valve. The problem is that the current quote to do the work is nearly half the value of the car, at over $2000. No other repairs have cost this much (she has owned the car since new). We will probably shop around and get some other quotes.
 
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Waco, TX
Originally Posted by mb32
The problem is that the current quote to do the work is nearly half the value of the car, at over $2000. No other repairs have cost this much (she has owned the car since new). We will probably shop around and get some other quotes.
YIKES! Maybe throw on a cheap Chinese eBay compressor and call it done.
 
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South Carolina
Originally Posted by Linctex
Originally Posted by mb32
The problem is that the current quote to do the work is nearly half the value of the car, at over $2000. No other repairs have cost this much (she has owned the car since new). We will probably shop around and get some other quotes.
YIKES! Maybe throw on a cheap Chinese eBay compressor and call it done.
Yes, I have to agree. ^^^ or simply a new compressor and always a new dryer..
 
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23,695
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MA, Mittelfranken.de
Originally Posted by Chris142
Originally Posted by mk378
This is the SD7V16 variable displacement compressor. Sometimes the failure is only the control valve being stuck at zero causing it to spin but not pump. The control valve can be replaced separate from the whole compressor but the refrigerant must be removed first. Especially considering it is 20 years old the receiver drier should be replaced any time the system is opened.
I though that too but I looked at the compressor and it does not have that valve that I could see
Unless you take it apart you wont see it. https://www.polarbearinc.com/articl...den%20sd7v16%20compressor%20tutorial.htm I have done a lot of these on MkIV cars, the compressor rarely comes apart inside so unless there are metallic particles in the lines going into the rear of the compressor the condenser can stay. The expansion valve on these can be a real bugger, it is held on with 2 long thin bolts that go through the valve into a plate on the evaporator, these thin bolts seize in the valve body. I have successfully cut the valve right down the middle where the screws are using a mirror to do the lower bolt, its not easy and easy to bugger up. I would leave the expansion valve and just change the compressor and receiver drier or you could end up putting an evaporator in it (big money). The Hella Behr Sanden (now called Mahl Clevite) is one of if not the best aftermarket unit on the market and at $200 is a deal, the ones I have used perform flawlessly and are one of the quietest units I have come across. Sanden and [censored]/Behr opened a factory in China to produce them, they also produce the parts for the "assembled" in USA Sanden ones. Unless the compressor had a catastrophic failure which is not the norm with these this is a very easy job costing less than $250 and about 1.5 hrs plus recharge. https://www.rockauto.com/en/moreinfo.php?pk=7001344&cc=1375556&jsn=417 The stupid friggin censor will not let me post the brand name H.E.L.L.A.
 
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47
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Canada
Thread starter
Originally Posted by Trav
Originally Posted by Chris142
Originally Posted by mk378
This is the SD7V16 variable displacement compressor. Sometimes the failure is only the control valve being stuck at zero causing it to spin but not pump. The control valve can be replaced separate from the whole compressor but the refrigerant must be removed first. Especially considering it is 20 years old the receiver drier should be replaced any time the system is opened.
I though that too but I looked at the compressor and it does not have that valve that I could see
Unless you take it apart you wont see it. https://www.polarbearinc.com/articl...den%20sd7v16%20compressor%20tutorial.htm I have done a lot of these on MkIV cars, the compressor rarely comes apart inside so unless there are metallic particles in the lines going into the rear of the compressor the condenser can stay. The expansion valve on these can be a real bugger, it is held on with 2 long thin bolts that go through the valve into a plate on the evaporator, these thin bolts seize in the valve body. I have successfully cut the valve right down the middle where the screws are using a mirror to do the lower bolt, its not easy and easy to bugger up. I would leave the expansion valve and just change the compressor and receiver drier or you could end up putting an evaporator in it (big money). The Hella Behr Sanden (now called Mahl Clevite) is one of if not the best aftermarket unit on the market and at $200 is a deal, the ones I have used perform flawlessly and are one of the quietest units I have come across. Sanden and [censored]/Behr opened a factory in China to produce them, they also produce the parts for the "assembled" in USA Sanden ones. Unless the compressor had a catastrophic failure which is not the norm with these this is a very easy job costing less than $250 and about 1.5 hrs plus recharge. https://www.rockauto.com/en/moreinfo.php?pk=7001344&cc=1375556&jsn=417 The stupid friggin censor will not let me post the brand name H.E.L.L.A.
I think replacing the compressor and drier makes sense given the age. I will take to another shop and see if they can inspect the oil that comes out of the compressor and lines.
 
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