Car A/C - Turn it off before shutting off the ignition ?

Discussion in 'Archived Threads 2001-2004' started by Kirk Gunn, Jul 29, 2002.

  1. Kirk Gunn

    Kirk Gunn Screenwriter

    Joined:
    Aug 16, 1999
    Messages:
    1,609
    Likes Received:
    0
    Trophy Points:
    0
    My dad always said you should shut off the A/C a few minutes before the car. Something about it equalizing the pressure in the compressor, and the seals would last longer.

    Makes sense, but any truth to this ? Thanks
     
  2. Michael Reuben

    Michael Reuben Studio Mogul

    Joined:
    Feb 12, 1998
    Messages:
    21,763
    Likes Received:
    3
    Trophy Points:
    0
    I fixed your thread title. Some typos can be a bit embarrassing. As originally written:

     
  3. Zen Butler

    Zen Butler Producer

    Joined:
    Jan 24, 2002
    Messages:
    5,540
    Likes Received:
    19
    Trophy Points:
    5,610
    Location:
    Southern, Ca
    Real Name:
    Zen K. Butler
    In 20 years, I have never heard of this. I asked our Master Tech, he says definite false. sorry [​IMG]
    but I'm sure this just may spark debate
     
  4. Jared_B

    Jared_B Supporting Actor

    Joined:
    May 7, 2001
    Messages:
    580
    Likes Received:
    0
    Trophy Points:
    0
    The only reason to do so is to prevent any musty smell upon startup. The condensor (i think that's what it is) in the AC system releases moisture when it's turned off. The moist air sits in the AC system until you start the car again, then it is blown into the cabin and usually stinks pretty bad. Turning off the AC before the car will allow this moist air to be circulated out of the system.
     
  5. Allen W

    Allen W Stunt Coordinator

    Joined:
    Dec 10, 2001
    Messages:
    62
    Likes Received:
    0
    Trophy Points:
    0
    Well I have to say I am a big believer in turning off the AC button 30 seconds before the engine.
    I have a 1990 Chevrolet pickup that is now going through it's thirteenth Texas summer with the original A/C compressor. Somebody told me years ago to turn off the little AC button (I leave the fan on) about 100 yards before I parked the car. I just incorporated into my daily driving, it is 2nd nature now. I have not added freon to the system in 5 years, so obviously the seals are holding.
    Try this little test, on my car you can hear it easily. Turn off the key with the AC running and see if you hear a psssshhhh sound under the hood of the AC compressor releasing the pressure. Then try it again but turn off the A/C 30 seconds before you turn off the key. On my car it's quiet.
     
  6. Leila Dougan

    Leila Dougan Screenwriter

    Joined:
    Mar 27, 2002
    Messages:
    1,352
    Likes Received:
    0
    Trophy Points:
    0
    I've heard the same thing Jared has. In addition to the musty smell, I also heard that if everything stays most it can start molding which I don't think is too great for the parts or your lungs.
     
  7. Ryan Wright

    Ryan Wright Screenwriter

    Joined:
    Jul 30, 2000
    Messages:
    1,875
    Likes Received:
    0
    Trophy Points:
    0
    I turn it off just before I park so I can use that last bit of cold air for "free" and save the .00002 cents worth of gas it would cost to run the compressor for that long. [​IMG]
    I also don't like to start my car with the A/C on, so it always gets turned off while I'm parking.
     
  8. Kevin P

    Kevin P Screenwriter

    Joined:
    Jan 18, 1999
    Messages:
    1,439
    Likes Received:
    0
    Trophy Points:
    0
     
  9. Wayne Bundrick

    Wayne Bundrick Cinematographer

    Joined:
    May 17, 1999
    Messages:
    2,358
    Likes Received:
    0
    Trophy Points:
    0
     
  10. Todd Hochard

    Todd Hochard Cinematographer

    Joined:
    Jan 24, 1999
    Messages:
    2,312
    Likes Received:
    0
    Trophy Points:
    0
     
  11. BrianW

    BrianW Cinematographer

    Joined:
    Jan 30, 1999
    Messages:
    2,563
    Likes Received:
    38
    Trophy Points:
    0
    Real Name:
    Brian
     
  12. Ken Garrison

    Ken Garrison Supporting Actor

    Joined:
    Jun 1, 2002
    Messages:
    543
    Likes Received:
    0
    Trophy Points:
    0
    I have a 1984 Toyota Van and I wanna know how much it'll cost to have the pump replaced and have it converted to the new freon crap? Napa told me around $500-700 bucks. Maybe I can save labor by removing the passenger seat and the panel underneath it before I drive it up there. Engine's located under my ass. LOL So, if I disassemble it and make the access better, then the labor should be lower. Then I can put it back together when I get her home.
     
  13. Allen W

    Allen W Stunt Coordinator

    Joined:
    Dec 10, 2001
    Messages:
    62
    Likes Received:
    0
    Trophy Points:
    0
    Brian - how many years are we going to have to go till one breaks and we find out who the final winner is! I do feel like I have gotten my moneys worth on this car. I sure don't have enough of a control group to prove that my A/C wouldn't have lasted this long without turning off the switch, but I'm sticking with my plan. Also I don't know what a vacuum controlled A/C duct is, I have never had to fix an A/C before [​IMG] .
    Todd - probably true that the A/C makes noise when you turn it off with the engine running. I think it has more time to gradually release the pressure rather than all at once when you after you turn off the motor. This is just a theory of mine, I don't actually know how they really work!
     
  14. Darren Davis

    Darren Davis Stunt Coordinator

    Joined:
    Oct 9, 2001
    Messages:
    248
    Likes Received:
    0
    Trophy Points:
    0
    Ken, my 89 Buick Skylark isn't blowing cold air right now and it seems to need more r12. Anyway, I just talked to my mechanic brother-in-law about the r12 to r34 conversion (via a kit) and it doesn't sound too promising. Everything in the A/C system needs to be sucked out because the refrigerant oil used for r12 isn't compatible with the r34 oil and when they mix a sludge is formed that clogs everything up causing the whole a/c system to not work. And, even after the conversion is done there's still no guarantee it'll work. He told me it's a "crap shoot." And, if it does work (and it can, my older brother told me he's done this to a few of his previously owned cars (GM)) the air might not run as cold as with the r12. Based on the lengthy discussion I had with the mechanic today I think I'll stick with the r12. At $70 a lb. it's not cheap but I think it's the safer way for me to go.

    Just my 2 shillings
     
  15. Ken Garrison

    Ken Garrison Supporting Actor

    Joined:
    Jun 1, 2002
    Messages:
    543
    Likes Received:
    0
    Trophy Points:
    0
    Well, I'll have it converted and see if that works. If the R 12 worked so much better, it sucks that them environmental wackos switched to something different. Ozone depletion is a myth.
     
  16. Kirk Gunn

    Kirk Gunn Screenwriter

    Joined:
    Aug 16, 1999
    Messages:
    1,609
    Likes Received:
    0
    Trophy Points:
    0
    Thanks folks ! And thanks for editing my Typo Michael !
     
  17. Todd Hochard

    Todd Hochard Cinematographer

    Joined:
    Jan 24, 1999
    Messages:
    2,312
    Likes Received:
    0
    Trophy Points:
    0
     
  18. Dan D.

    Dan D. Stunt Coordinator

    Joined:
    Aug 29, 1999
    Messages:
    215
    Likes Received:
    0
    Trophy Points:
    0
    For all those unaware, another good a/c longevity tip is to run the compressor a few minutes at least once a month during the winter to keep the seals lubricated. Nine years on my '93 Civic Si and no recharges yet - still running cold.
     
  19. Carlo Medina

    Carlo Medina Executive Producer

    Joined:
    Oct 31, 1997
    Messages:
    10,580
    Likes Received:
    747
    Trophy Points:
    9,110
    You know, I've never "heard" to do this or not to do this...

    It's just something I do anyway. Don't know why, it just seemed to make sense. Go figure...
     
  20. Ryan Wright

    Ryan Wright Screenwriter

    Joined:
    Jul 30, 2000
    Messages:
    1,875
    Likes Received:
    0
    Trophy Points:
    0
     

Share This Page