Solar Ventilation System Question

Leave the button pressed in in the summer time and the fan will run. The button is for the winter time. It will cool the car to the outside temp in the winter.

 

Huh?

 

In other words, you wouldn't want fans running in your car to cool things down in the winter months. Therefore, you've got a button in order to turn them off for the winter.

 

Actually I believe that in the winter it will still only keep it cooled to the level you set the temp at, on a cool summer day the solar vent does not come on if the cabin temp is less then 24C which is my set temperature.

Just will run less often in the winter

 

The owners manual explains the importance of the button in the winter.

 

I think I read information about the Solar Roof that said it only worked when the outside temp. was above 68 degrees. The Owners Manual says the solar panel must be completely in sunlight and at a "high temperature", which would preclude operating during the winter. I've gotten into my car when the winter temps are in the 35 degree range and the car has been hot because of the effects of the sun at the altitudes we have in Colorado. It will be interesting to see if the direct sun during the winter in Denver will trigger the solar ventilation. --TK

 

Here's the source: Toyota Prius

It says "The Solar Powered Ventilation System uses an electric fan to draw outside air into, through, and out of the cabin once the inside temperature reaches 68 degrees Fahrenheit. It will lower the cabin temperature to near the outside ambient temperature to help make the cabin more comfortable when reentering the vehicle. It must be turned on prior to leaving the vehicle and cannot perform cooling such as with an air conditioner."

Using the inside temp. makes more sense than what I remembered. After reading, at least scanning, the owners manual, the DVD, the Navigation package manual, it's a small wonder I remembered anything. I felt the Solar Ventilation made sense in the Denver area because of the amount of sunny days, the lack of cloudy, overcast days, the lack of shade or covered parking, and what feels like the compounding effect of the heat of the sun at 5,000+ feet in altitude. --TK

 

I have had mine for over a month now and finally went out and bought a thermometer to test the SR stystem because it just hasn't seemed that effective.

For the last several days, I have left the system running, then after about 4-5 hours I turn on the car to get the outside temp and compare it to the inside temp. The average temp inside the car has been about 13° hotter than the outside temp. The closest it ever got to the outside temp was 8°. This doesn't sound ambient to me.

My salesman suggested opening the windows a crack, but that didn't seem to make any difference. I have also used the remote AC very little bc then I can't test the inside temp.

I am at my wits end! What am I doing wrong? Is it time to call the dealer?

 

Have you tried doing a similar test to see what the difference between outside and inside temperature would be without the solar roof running? Is the roof actually running? Only 13F above ambient is really not that bad, considering the car has a black roof and a ton of glass. But the comparison without the roof turned on would give you a better idea of how much good it's doing you. It's certainly never going to actually reach ambient, so perhaps you're just expecting a bit much?

 

Can you provide more info? What was the weather like--was it overcast or really sunny? What was the outside temperature? Did you feel the fans (so you know the ventilation system was working)? How much were the windows cracked?

Dependent on these factors, I think an 8-13 degree difference might be pretty good. I've been testing my current car so I have a comparison for when I get my IV with SR, and miy inside temps have been 20-25 degrees higher than the outside temp of upper 90s to low 100s, and that's with the windows pretty widely cracked (~2 inches) and parked in full sun. I've been using an instant read kitchen thermometer, so it's not the ideal instrument, but it's all I have on hand.

Your results are about half that so that seems pretty good to me if your conditions are comparable to mine, but as I said, I don't think you've provided enough info to really tell anything.

 

Also, bear in mind, that the AC isn't running, just the climate control fan... the best you can really hope for here is the same as if you sat in the car with the climate control turned on, the air source set to outside instead of recirc, and the AC button not lit. That's the best the solar roof can ever do. And if it doesn't get enough sun to fully power the fan, it won't even do that much.

 

I will be getting my car soon, so I don't have any actual experience with it yet.
However, I am pretty sure that simply keeping the air flowing inside the car, even without A/C, will make a difference.
Let's not forget that the solar roof and ventilation comes bundled with the remote A/C function. I'm sure they're kinda meant to be used together.
Even without using the remote A/C, the car should cool off a lot quicker once you actually get inside and DO turn on the A/C.

I would have gotten the sunroof anyway, even without the solar ventilation.
I like sunroofs.

 

I have had the system turned on in full & partly sunny days. For instance, yesterday the outside temp on a mostly sunny day was 81°. After 5½ hours (7:30am to 1pm) in a parking lot with no tree cover the inside temp was 97.6°. That's almost a full 18° hotter.

When trying it with the windows open, I usually crack all 4 windows about 1-1½ in. I have tried it at work, at home (in a driveway with no tree cover), in store parking lots, etc. always with similar results.

Ambient by definition means "surrounding", which in my book aren't the results the SR is achieving. I may have my expectations set too high, but no matter how you look at it an 18° difference isn't ambient. At best it's a modest difference, that when coupled with the remote A/C is better than nothing. I just can't believe that I am the only one having this experience.

The fact is that I am beyond thrilled with the rest of the car, but terribly disappointed with the SR.

 

I tested my car against a similar car without the sunroof, parked in the same place, on the same day, etc. The differences were substantial. While my car was above ambient temperature, it was 20 or so degrees less than the other car. That is a big load off of the AC system when turned on, and it is also the difference between being burned by the hot metal and steering wheel inside the car.

You do have the sunroof slider closed right? (I don't know what to call it, but it is the thing in the roof that slides over to block the sunroof).

You are not the only one who has the solar roof and does not have the inside at ambient. I don't either. All of that glass makes the inside of the car a greenhouse. The solar roof cannot keep a greenhouse like that at ambient temps. At worst, my car is comfortable to drive 1 to 2 minutes after turning it on... not bad for Florida.

And I'll add that Toyota made a point to measure its effectiveness using the remote AC button. I will add that under every situation it has been in, inlcuding a 98 degree Tampa day with the car parked in the open sun from 10:00 AM until 3:00 PM... that it only took the car two minutes to be confortable.

Had I used the remote AC before getting in, it would have been perfect the first time I opned the doors. I think that is the intention. Do you often use the remote AC before getting in?

 

Point taken. Ambient must have a broader definition to Toyota. And to answer your question, yes, the slider door was clsed and I have been using a 2010 heatshield each time. IMO, anyone who doesn't get a heatshield is nuts. It is great! So good in fact that I bought 3 more for the rest of the family cars.

I will now try to remember to use the remote AC more and stop complaining.

It really is a great feature. And the sunroof is so fun!