I like science, go on!Welly wrote:But there's the issue, you turn on the a/c in winter - the moisture that collects in the evaporator box sits there and when you leave it fogs the windscreen because the windscreen is really cold on the outside. You then need to run the a/c to get rid of the condensation - this becomes a deadly cycle if you like.
I don't run my a/c and I have no condystation problems.
The only time I would see this 'dehumidifying' as a benefit would be when 4 people jump in the car with wet clothes on a coldish day. The rapid demisting would be useful, temporarily.
I might carry out an experiment with my digital hygrometer to compare a/c on or off to see what goes, it has a recordable Max & Min memory so would be interesting.
The dehumidification of summer air is welcomed as it helps our skin vaporise sweat and therefore cool, you're unlikely to get a foggy screen in summer because it's too warm out there.
Disable ac on startup
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- OdinEidolon
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Re: Disable ac on startup
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Re: Disable ac on startup
I thought A/C didn't work below a certain temperature? 4c isn't it? So even if the MFD says it's on, is it?
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Re: Disable ac on startup
The mfd will still say its on even if you totaly disconect it.D9406 wrote:I thought A/C didn't work below a certain temperature? 4c isn't it? So even if the MFD says it's on, is it?
And I think this is one of those debates that could go round in circles till the end of time. I just leave mine on auto, cause I think thats the whole point of climate control, to leave it to control things on its own. My cars never steam up when parked though. Does with people in it and no ac though. But perhaps the drains on them arent blocked?
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Re: Disable ac on startup
I think you are right about it not coming on below a certain temp but not sure what temp.D9406 wrote:I thought A/C didn't work below a certain temperature? 4c isn't it? So even if the MFD says it's on, is it?
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- OdinEidolon
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Re: Disable ac on startup
I guess apart from a °C sensor there's also a humidity sensor somewhere that may trigger the AC on even if it's cold?
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Re: Disable ac on startup
AFAIK the auto function / auto A/C works because of the difference that is set manually and the difference that is outside, so i would go with what steve earwig said early ...
What i did notice is that, if you turn the A/C off and you turn off the motor, and return in +/- 2 hours, your settings will still be the same, but if you return later it will be auto again .. well this is my experience.
when it's 12:30 ( time where i go home for lunch ),some days the interior of my windscreen is full of humidity it even forms water bubbles . Is this normal ? Not even A/C can remove it in few time...
What i did notice is that, if you turn the A/C off and you turn off the motor, and return in +/- 2 hours, your settings will still be the same, but if you return later it will be auto again .. well this is my experience.
when it's 12:30 ( time where i go home for lunch ),some days the interior of my windscreen is full of humidity it even forms water bubbles . Is this normal ? Not even A/C can remove it in few time...
2000/May 406 Estate 2.0 HDI 110bhp DW10ATED now with 205k km & now with cruise control & now remaped @ 134bhp 

- OdinEidolon
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Re: Disable ac on startup
This is what happens to me too.RayneR wrote:What i did notice is that, if you turn the A/C off and you turn off the motor, and return in +/- 2 hours, your settings will still be the same, but if you return later it will be auto again .. well this is my experience.
Mine never steams up. Maybe there's less humidity here, but I've owned the car 10 months and up to now I never seen it steam, even with 5 people inside.RayneR wrote:when it's 12:30 ( time where i go home for lunch ),some days the interior of my windscreen is full of humidity it even forms water bubbles . Is this normal ? Not even A/C can remove it in few time...
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Re: Disable ac on startup
So can I ask a question about it? If the temperature is really cold, like its been recently, if its set to auto is it clever enough to heat up the interior to a decent temperature? I always stick it on manual and put it up around 72 at the moment. Would it adjust the fan speed too?
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- OdinEidolon
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Re: Disable ac on startup
Of course. The AC light is for cooling the car down, the car brings itself up to the specified temp no matter if the AC light is on. AC is for cooling and or demisting.leestudd30 wrote:So can I ask a question about it? If the temperature is really cold, like its been recently, if its set to auto is it clever enough to heat up the interior to a decent temperature? I always stick it on manual and put it up around 72 at the moment. Would it adjust the fan speed too?
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