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One More AC Smell Thread: How to REMOVE (not prevent) smell? (class action lawsuit?)

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by westville, Oct 21, 2015.

  1. 4rpr15

    4rpr15 Senior Member

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    So when I press Auto when I need heat I should also press a/c which turns it off?
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    I'm thinking the system's behaviour might be different on the US model, than (my) Canadian. If I've got the AC off (light on the AC button off) and press AUTO, the AC button light stays off. Is it different in the 'States, ie: push AUTO and the AC button goes on? Or has a good chance of going on?

    Our previous car was like that: had an Auto setting which turned on AC, so I was constantly hitting Auto and then turning AC off.

    With mine, with one exception, AC will not be running if the AC button light is off. The one exception is if Mode is set to Heat/Defog, then AC may turn on/off. It tends to be low wattage, and intermittent. I've monitored the AC compressor wattage use, with ScanGauge, to be sure.

    Heat/Defog mode:

    Capture.JPG
     
  3. 4rpr15

    4rpr15 Senior Member

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    When I press Auto the A/C light turns on. If I press the A/C button to turn it off then after some time the windows get foggy.
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    That fogging up will invariably happen if you've been running AC for the last few minutes. If you hang in there, crack the windows, it'll clear. If the car's sat overnight, then you start up without AC, you shouldn't get any fogging.

    Pretty much the only times I'll use AC:

    1. Extended highway driving.

    2. Rain, when cracking the windows doesn't cut it. The first way I'll use AC is by just switching mode to Heat/Defog. This will activate AC, without turning on the indicator light on the AC button, at least on my Canadian car, and it tends to run the compressor sparingly, at low wattage. And if that doesn't cut it, then I'll expressly push the AC button too.
     
  5. 4rpr15

    4rpr15 Senior Member

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    Here in the Midwest USA it's going to start getting cold. Why does the A/C button stay on when I'm trying to heat the car? So I should manually press it off whenever I click Auto on when I need the heat on?
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    I'd try that first.

    This is different than ours, btw. Maybe cus it's a 2010, or Canadian model, not sure. If I've got AC button off, and hit Auto, the AC button does not light.

    This is just the way I like it. It's frustrating to repeatedly have to hit Auto, and then switch off AC. I can see people just throwing up their hands, going with the flow. But constant AC is use is not necessary, cuts into your mpg, and per the testimonies, promotes mildew/mold growth.

    We got pretty much weaned off AC by one of our sons, who hates it, had a conniption fit if he was in the car and I turned it on. I didn't use it that much to begin with, but after a road trip or two with him along, I came around, even more. :)
     
    #26 Mendel Leisk, Oct 23, 2015
    Last edited: Oct 23, 2015
  7. 4rpr15

    4rpr15 Senior Member

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    I'm just wondering why A/C stays on when we press Auto? Especially if we're trying to heat the car.
     
  8. bisco

    bisco cookie crumbler

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    it may be that the japanese think of air conditioning as air conditioning, not air cooling.

    have you studied the hvac in the manual?
     
  9. 4rpr15

    4rpr15 Senior Member

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    I can easily see turning A/C back on during the winter especially when the windows start fogging up constantly. I checked out the manual off and on and found no help there.
     
  10. bisco

    bisco cookie crumbler

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    it may run to some extent, as long as there is humidity inside the car.
     
  11. 4rpr15

    4rpr15 Senior Member

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    I have noticed that it never turns off when Auto is enabled.
     
  12. bisco

    bisco cookie crumbler

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    i think mendel has tracked a/c on/off with his scan gauge.i believe it shows current draw. i'm not entirely sure what the light on the button means.
     
  13. CR94

    CR94 Senior Member

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    Mine behaves the same as your description, I think. In fact, if the temperature setting is below the outside temperature on a hot day and I press the AUTO button, but not the AC one, the fan promptly revs up to its top speed, attempting the impossible task of cooling the interior with uncooled air.

    I agree, as far as avoiding overuse of the compressor. It should be used only as much as necessary to avoid window fogging or thermal distress. I've never noticed any odor from the HVAC system. Evidently the previous owner didn't have that problem, either.
     
  14. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah the Owners Manual uses the term Air Conditioning to mean any and all air movement through the system. Confusin.
     
    AltraStache likes this.
  15. 4rpr15

    4rpr15 Senior Member

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    What would you recommend for us who have to use heat for many months to cut mpg's, reduce fog and to keep the inside warm? Press A/C off and just turn it on when it's foggy and then turn it off again when the fog goes away?
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Keep AC off as much as possible. I typically set temp at 21.5C and have it on Auto, with AC off.

    If and when windows are starting to fog, and cracking the windows is not cutting it, or just not practical, then first try setting Mode to Heat/Defog. This'll use AC but lightly. If you're still fogging, then push the AC button.

    Anytime you use AC for more than a minute or two, when you turn it off you get a humidity dump. Sometimes you can live with it, by cracking windows. Sometimes it's too risky.

    Running the system without AC for say 10 minutes, it will clear up. Or sitting overnight.

    One caveat: you do want to use some AC at least maybe once a month, to circulate the oil in the system.
     
  17. 4rpr15

    4rpr15 Senior Member

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    Why does the system automatically go into A/C mode when much warmer temps are selected and why doesn't the A/C mode ever turn off?

    Also, what about the summer? Keep
    A/C off still?
     
  18. Mendel Leisk

    Mendel Leisk Senior Member

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    That's different than mine, AC stays off, even if I hit Auto, on my 2010.

    On warm summer days, we just shut it right off, and roll the windows down.

    Once in a while on the highway might use AC, but rarely.
     
  19. 4rpr15

    4rpr15 Senior Member

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    Let me explain. When the vehicle starts I press Auto and the A/C button lights on automatically. If I manually press A/C it goes off and stays off. But when I press Auto and I don't press A/C it never turns off.
     
  20. Mendel Leisk

    Mendel Leisk Senior Member

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    So hit Auto then turn off AC?