Results 1 to 7 of 7
  1. #1
    Join Date
    Sep 2015
    Location
    Dubai
    Posts
    4

    Default A/C related : Do I really need a new Expansion Valve, Evaporator and Receiver 2008 V8

    I took my V8 XC90 2008 into the Garage today to get some Shocks fitted at the front and also to ask them to check the Aircon.

    It just doesn't seem to blow ice cold. It blows cool, but not cold.

    I had the system Re-gassed and I've checked the Compressor clutch for engagement - looks good.

    I've read a few posts, after the compressor going bad (it's a 2008/9 so not sure it's this) - one pointed to the Front Condensor.

    The Garage though reckons I need the following replacing:

    1. Expansion Valve
    2. Evaporator - behind the dash, ouch
    3. Receiver Dryer

    Trouble is I'm in Dubai and it's hot - 40 degrees C and I'm not sure if that's correct?
    Sounds expensive as it's a dash out exercise.

    Has anyone got any advice, experience to share on where to start as I'm planning to source the parts and get them to install.
    Which parts should I get, AC is essential out here in the desert and its getting hotter every day.

    Thanks

  2. #2
    Join Date
    Dec 2009
    Location
    GA
    Posts
    1,420

    Default

    You have a variable displacement compressor on that engine. The valve that controls the displacement may be bad. (30665603)
    Have replaced many of those valves to solve poor cooling issues. Have not seen a bad Volvo expansion valve since they started using them again in ~2001.

    You can check the duty cycle the climate control unit is sending to the valve with VIDA - that would be my first step after knowing the correct refrigerant charge is in the system.

    Other manufacturers (VW and Audi I know) use similar valves to control the displacement of their compressors also.

    How does it vary the displacement? - the valve uses refrigerant pressure to change the angle of the swash plate according to the cooling needed - https://www.youtube.com/watch?v=znEaHChgAlE

    or
    https://www.youtube.com/watch?v=_CnIP85oY3o

  3. #3
    Join Date
    Sep 2015
    Location
    Dubai
    Posts
    4

    Default

    Howdee and thanks for taking the time to reply, very kind - its experts like you that help lay people like me save money!

    So, I've not got access to VIDA and the Dealers here charge buckets for this sort of diagnosis.
    Would you replace the control valve as a Matter of course then? They seem to be around $50 on ebay.com - I've gone ahead and found the other parts - circa $200 so far and they are on the way to me.

    Would you recommend I do what the garage says and see if that fixes it then - my issue is I think they may be guessing - how would they know that these need replacing?
    One guy with a V8 on the forum said that replacing the Condensor fixed it...

    What would you do?

  4. #4
    Join Date
    Sep 2015
    Location
    Dubai
    Posts
    4

    Default

    Quote Originally Posted by hoonk View Post
    You have a variable displacement compressor on that engine. The valve that controls the displacement may be bad. (30665603)
    Just another thought, would an ODB type reader pick up any codes in the Air Con Area i.e. Bad Control Valve?

  5. #5
    Join Date
    Dec 2009
    Location
    GA
    Posts
    1,420

    Default

    Quote Originally Posted by bluebossa View Post

    1. So, I've not got access to VIDA and the Dealers here charge buckets for this sort of diagnosis.

    2. Would you replace the control valve as a Matter of course then?

    3. Would you recommend I do what the garage says and see if that fixes it then -

    4. My issue is I think they may be guessing -

    5. How would they know that these need replacing?

    6. One guy with a V8 on the forum said that replacing the Condensor fixed it...

    1. You would want your service provider to diagnose and complete the job (not just diagnose) - so there would be some accountability (if what they diagnose doesn't fix it, they put it back the way is was at no charge, or fix the right thing the second time at a reduced rate or free)

    "charge buckets" - Black market VIDA copies and chinese dice clones are available for less than $150 -

    2. Not without proof that it is bad (back to diagnosis is expected to fix problem)

    3. Not without proof the evaporator/expansion valve is bad, or yes with the understanding that it wont cost you parts and labor if it does not fix the problem.

    4. Might be or just not good with ac work (or want to chase you away with a large estimate)

    5. Pressures, readable with vida and external gauges, evap temps -readable with vida, compressor valve duty cycle -readable with vida. I have replaced many evap temp sensors (a ~$40 part) that prevented ac systems from working properly also.

    6. Yes, condensers are known to crack near the tabs that the drier is bolted to. (and the refrigerant leaks out, but low refrigerant was not your diagnosis)

    You said you have parts ordered - are you really going to have someone take your dash out to replace the evaporator if you are not sure that is what is needed? (that a multi hour job - it will cost "buckets")

    And what professional shop will install ebay parts with any warranty at all? Why would you go anywhere else but a professional shop - because it is cheaper?

  6. #6
    Join Date
    Dec 2009
    Location
    GA
    Posts
    1,420

    Default

    Quote Originally Posted by bluebossa View Post
    It blows cool, but not cold.
    What is the exact temp? Normal functioning systems blow 45F to 50F degrees.

  7. #7
    Join Date
    Nov 2010
    Location
    Albuquerque
    Posts
    10

    Default

    Replace the compressor control valve, they get dirty and the original design was improved, cool, semi cool or similar performance is usually this 100 control valve it's an inexpensive part - volvo PN (31305844) relative to a new or used compressor and takes about 30 minutes install, it can be accessed from the bottom of the V8 you will need to get the system evacuated first at jiffy lube or similar, replace the valve then re-fill the system I'd also recommend replacing the receiver dryer for optimum performance. this is an easy job that will save you thousands

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •