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Auto-AC Button on Steering Wheel

Discussion in 'Gen 2 Prius Technical Discussion' started by anti-gas, Jul 29, 2008.

  1. doubleg2005

    doubleg2005 Member

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    yesterday after my teacher inservice i got back into my car (3pm-ish) and the MFD thermometer read 133*

    took 45 minutes for the A/C to get the temperature down to 80... :(
    but it DID slow down as it approached 80 inside, just as it's supposed to. then there's the fact that the outside temp finally "cooled down" and settled in at 104. a 24* differential from inside to outside is pretty significant if you ask me. good thing Pablo's AC is so effecient! :D
     
  2. rigormortis

    rigormortis Active Member

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    try it sometime. it has been my observation that at times the internal combustian engine will fire up for no other logical reason other then to keep the cabin warm.

    now if the internal combustion engine fires up at longer intervals like at least 5-10 minutes, its pretty obvious that its charging the battery up

    but if you keep the cabin air temperature down, the engine will only stay on for a couple minutes, here and there, and then shut down for the 30 minute period


    the prius's traction battery fully charged (as defined as 70 %, heh) has enough energy stored in it to keep the car in full ready mode, in park, for at least 30 minutes without needing the internal combustion engine to charge it.

    find a couple stop watches and you will notice that the gasoline engine will fire up more often in a prius car with its cabin temp set higher then the other prius car with its cabin temp set lower

    can you hear the battery cooling fan? i have never heard it comming on

    most of the time on my 30 minute lunch breaks at 2:35 am in the morning
    i sit in my car in full ready mode (because at 30-45 minutes in accessory mode is kind of pushing it), 5 days a week, and theres a direct link from what i have seen so far

    after you have tried this and it seems to be the case please report back on the following section

    totally unproven theory section
    =======================
    the prius fuel tank has a sensor in it to correct the fuel level when you go up and down hills, the headlight sensor will adjust the HID lights as you go up and down hills, these sensors report back to the prius and the prius takes this information and forces your car to burn gasoline @ 25 mpg uphill to keep the battery safe so it lasts a long time
     
  3. qbee42

    qbee42 My other car is a boat

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    This is unquestionably true in the winter, when the ICE is supplying heat for the cabin, but I assume you are discussing summer cooling. With cooling, the situation you describe comes from removing humidity. The Prius climate control system uses a sensor to detect humidity and runs the A/C compressor as needed to keep the humidity to a reasonable level. If the conditioned air feels to cold when it enters the cabin, you raise the setpoint. Now the controller has a dilemma: cut the cooling and allow the humidity to rise, or add heat from the ICE. In this case the A/C controller will reheat the cold air with heat extracted from the ICE. This kind of operation is common with air conditioning systems running in hot humid weather. The same thing happens when you run defrost in the winter.

    Tom
     
  4. DaveinOlyWA

    DaveinOlyWA 3rd Time was Solariffic!!

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    just returned from a 900 mile trip over 5 days and we also started AC at 70... but as the drive goes on and the humidity of the air goes down and cabin temp equalizes, (not easy because of the radiant energy of full sun) our comfort needs eventually had us at 75º... now that might not seem good to most, but keep in mind, temperatures are all relative and based on what you are acclimated to. daily average high temps in summer around here is 77º

    in the south where temps are much higher, one could probably set temps to 80 and be ok.