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Amateur level HVAC question

Discussion in 'Prime Technical Discussion' started by mdhare, Feb 25, 2017.

  1. mdhare

    mdhare Member

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    Bear with me in that I'm coming from a 2005 baseline Honda with manual HVAC controls to a Prime.

    Is there a way to run the circulation fan bringing in just outside air without the car trying to heat/cool?

    I haven't had enough chance for trial/error to figure this out. I did RTFM but it didn't help.

    * Can I get this behavior if I disable "auto" mode and pick a fan speed, or will it still try to hit my requested temperature?

    * Winter where I'm at and often below 32F, can I achieve this in winter by setting a really low desired temperature? Presumably if I set it for 50F (for example) and it's 32F outside it won't try to turn on the air conditioner? I haven't seen what the bottom temperature is but for example I know if you try to warm over 85F it says "Hi" or something like that instead, I found this out experimenting with Remote A/C.

    I guess I could always open a window.. :)
     
    #1 mdhare, Feb 25, 2017
  2. bisco

    bisco cookie crumbler

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    disable auto, pick a fan speed, lower temp to 'low', and make sure it's on fresh air, not recirculate.
     
    #2 bisco, Feb 25, 2017
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  3. Tideland Prius

    Tideland Prius Moderator of the North
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    When you're in AUTO mode, changing a particular feature will put just that feature in manual mode (but all others that you didn't touch will be automatic). The AUTO light will not be highlighted on the screen (or on the HVAC control depending if you have the 7" or 11.6" screen).

    So if you pick a fan speed, it will keep the temperature that you chose (but may either take longer or may never get there because you picked your own fan speed)

    In the winter, just set it to "LO" if you just want circulation and not worry whether there's any warm air coming through.


    Note that if you're in AUTO with the A/C light on and you go into manual mode, the A/C will run so turn it off manually if that's what you want. (The A/C light in AUTO means it'll run as needed)
     
    #3 Tideland Prius, Feb 26, 2017
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  4. mdhare

    mdhare Member

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    Thanks, will give it a shot
     
    #4 mdhare, Feb 26, 2017
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Is there a way to turn the system off with various manual settings, then turn it back on with those same settings? Or is the only option to turn it on to hit "Auto", then reset things? It's not overly complicated to the latter, but a little tedious. I know with our previous Civic in that scenario, if you pushed the fan speed increase button once, it would wake the system up, with previous settings.
     
    #5 Mendel Leisk, Feb 26, 2017
  6. Tideland Prius

    Tideland Prius Moderator of the North
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    If the HVAC is off, just turn the fan speed up to the minimum speed. (So press fan speed increase rather than the AUTO button)
     
    #6 Tideland Prius, Feb 26, 2017
  7. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah I was thinking that! I tried it (2010 Prius) and thought it backfired, turned the system on but seemed to have locked fan speed. Say, in a case where I'd previously set auto, then overrode vent mode only, left fan speed on auto.

    I know it worked thus on our previous Civic. I'll have to try it again, not that sure. Thanks!
     
    #7 Mendel Leisk, Feb 26, 2017
  8. Tideland Prius

    Tideland Prius Moderator of the North
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    Hmm. I've never tried it but based on how the system reacts, it seems logical for it to work the way I described above.

    If you overrode the vent mode and turn the system off, then back on using the fan speed, then now both vent and fan are in manual mode. (well I guess that means it's fully manual)
     
    #8 Tideland Prius, Feb 27, 2017
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  9. Mendel Leisk

    Mendel Leisk Senior Member

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    I wonder if I could "awaken" it by pushing the mode button. I'll give that a try. Basically I've got mode set, and fan speed automatic, and am hoping to preserve that when waking it.
     
    #9 Mendel Leisk, Feb 27, 2017
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  10. Tideland Prius

    Tideland Prius Moderator of the North
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    I doubt it but you could try.
     
    #10 Tideland Prius, Feb 27, 2017
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