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solar roof fan

Discussion in 'Gen 3 Prius Main Forum' started by carbon fp, Dec 31, 2009.

  1. carbon fp

    carbon fp New Member

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    Does anyone know how can I tell if the solar fan is set to go on when I park my car? The on off switch seems confusing. thanks
     
  2. codybigdog123

    codybigdog123 Got Mad and Left in a Tizzy

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    If the solar fan has been activated, you should be able to feel that the solar fan button feels slightly depressed (ie, no longer flush). It doesn't depress very much, but you should be able to feel the difference bewteen the on, and off positions. I think Toyota could have done a better job with the ergonomics of this button.

    The system takes about 10 minutes (or so) before it activates after the car is locked. Assuming you have sunny conditions, the fan in the cabin of the car will come on for short periods of time if, and only if, the cabin temperature equals/exceeds the exterior/outside temperature. The fan speed is quite low, so often hard to tell when it's working unless you put your hands up to the air vents to feel it working. But it does definitley keep the cabin cooler in the Summer (when you need it most). I don't use it at all in the Fall or Winter months.
     
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  3. Southern Traveler

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    Thanks for explaining regarding solar fan button. I had planned to read and understand operation of the solar panel this weekend, although that option will not be needed until spring (32-40 degrees currently in South). Happy New Year to All.
     
  4. paulemus

    paulemus New Member

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    Does anyone know how well it works in the shade. I generally get a parking space at work below some palm trees that provide shade most of the time. But I think solar works somewhat in daylight?
     
  5. codybigdog123

    codybigdog123 Got Mad and Left in a Tizzy

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    I'm not a solar power expert, but I think the solar panels need a certain amout of light (intensity) inorder to generate the voltage needed to operate the cooling fan. That said, they work best in direct sun light...not sure if they will work in the shade, or on cloudy day. I doubt that they will. But then again, if you're in the shade, the interior of the car should NOT be heating up due to solar radiation (which is really what the system is designed to reduce).

    Remember, the system is designed only to help equilibrate the cabin temperature with the outside temperature. If the temperature outside is hot, but cloudy/shaded, the inside of the car should not be appreciably hotter, and therfore, no solar coolling should be needed.
     
  6. Paradox

    Paradox Prius Enthusiast / Moderator
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    You can search around some older threads from around June; Someone took a little strip of red vinyl tape and put it on the bottom of the trim below the button so they could see when the button was pressed in better. If I can find the thread myself I'll put a link up to it.
     
  7. Paradox

    Paradox Prius Enthusiast / Moderator
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  8. codybigdog123

    codybigdog123 Got Mad and Left in a Tizzy

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    That's actually very clever. Thanks for the post, and to whomever though of doing this...good idea.
     
  9. HTMLSpinnr

    HTMLSpinnr Super Moderator
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    Clarification - in the winter w/ lower sun declination, the solar panels aren't as effective - you may hear the fan groan a bit, start up, then stop - even during mid-day unless you're parked w/ the trunk end directed toward the sun (south for North America).

    When operating with full sun, the fan runs at about a medium speed and is definitely audible.
     
  10. Hy-Bird

    Hy-Bird Junior Member

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    The solar panel doesn't use battery power right? Some people say it doesn't and some say it does. Which is which?
     
  11. AussieDave

    AussieDave New Member

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    The fan on mine keeps running after I get in the car. Even in a bit of shade or on a dull day there is a bit of air movement - less than the lowest setting but still significant.

    On a really sunny day it seems to build up to hurrican strength.

    The remote aircon is good but it stops the moment the SKS system opens a door. Also it seems to put it into recirc mode each time.

    David
     
  12. HTMLSpinnr

    HTMLSpinnr Super Moderator
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    It would stand to reason that the solar ECU would need some AUX 12V power to get started.

    Looking at the EWD - it looks like the ECU's still have battery tie-in via other fused circuits. There is a relay in play, however that when in the non-enegergized state, bridges blower motor power from the solar panel instead of the 50A heater/blower circuit. When the car is in accessory, ig-on, or ready modes, the relay is energized, disconnects the panel and connects the battery (12V system) as the blower motor source.

    The NCF guide suggests that the solar ECU also runs on solar power. Per the EWD, there are a couple of unidentified tie-ins between the solar ECU and the A/C Amplifier ECU, one which may be solar power (the other is the dash switch state, which would tell the damper to switch to fresh air after shutting down the car).

    Based on this, I'd say that the control circuits require some battery power to operate the fresh/recirc damper initially, however everything from then-on appears to be solar powered as well.
     
  13. hlkc

    hlkc New Member

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    Sat in the car for a lunch break and all the suddenly the air blowing into my face. The air is definitely lot more than I can ask for and it definitely help my interior today, 60 here and sunny. Let's see how it performs in 90+ in summer days!