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Discussion Starter · #1 ·
Hello,

What's the difference between Heat and A/C? Doesn't A/C heat up the car? I would have thought A/C would do both (heat up and cool down) depending on the temperature setting?

Vehicle Car Motor vehicle Plant Personal luxury car
 

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Heat pumps transfer heat, at the cool end there will be condensation on the cooling plate.
A) Air conditioning - warm air is cooled down and is dehumidifier, less condensation on your window.
B) cold air is heated up, but no condensation of moisture.

C) A/C air (dehumidifier, dry ) is then heated by a second heat pump for warm air, so 2x heat pumps. Ask @donald especially about Zoe.
 

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Discussion Starter · #3 ·
Heat pumps transfer heat, at the cool end there will be condensation on the cooling plate.
A) Air conditioning - warm air is cooled down and is dehumidifier, less condensation on your window.
B) cold air is heated up, but no condensation of moisture.

C) A/C air (dehumidifier, dry ) is then heated by a second heat pump for warm air, so 2x heat pumps. Ask @donald especially about Zoe.
And in plain English?
 

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And in plain English?
Press the auto button and leave it to its own devices?

It looks very like my one. I've never noticed the A/C light on, but the heat one often is. The heat pump can draw heat from outside to heat the cabin, which I think is heat, or it can reverse and take heat from the cabin and pump it outside, which is A/C.
 

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GOLF GTE PHEV
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Press the auto button and leave it to its own devices?

It looks very like my one. I've never noticed the A/C light on, but the heat one often is. The heat pump can draw heat from outside to heat the cabin, which I think is heat, or it can reverse and take heat from the cabin and pump it outside, which is A/C.
That would not provide any dehumidification! A/C passes incoming air over the condenser to remove moisture.
You can have A/C only if I remember correctly, but this will cool the interior so not much use without 'heat' this time of year.
Also note that you can have the fan on without either heat or A/C which is useful in warmer weather when you do not want either.
 

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And in plain English?
A heat pump can pump heat in either direction, depending on the configuration of expansion and compression.

A liquid forced to expand and become a gas has to drag heat out from somewhere.
A gas forced back into a liquid by compression has to dump its heat somewhere.

So do the first one first where it is cold (making the cold place even colder) and the second where you want heat (making the hotter place hotter still) and bingo, heat drawn from cold!

If you reverse the order, vice versa, you get the heat from the cabin dumped into the outside hotter place.

[This is called a Rankine cycle. It can be reversed to make a Rankine engine, which is how some steam engines work.]


If you cool the air, the water vapour cannot be sustained (the dew point falls) and water condensation comes out. So to make the air drier AND hotter you need to first cool the air down, then heat it back up more than you cooled it.

This can be done with just one pump and clever plumbing. Renault/Nissan have a patent to do exactly that. But somewhere along the line of dumbf-kery, they implemented the Zoe so it can only heat or cool.
 

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I always keep the A/C on to prevent fogging on the windows, If I don't preheat, then I set the heater temperature to 20°c and the fan to 4. After a miles or so it's nice and warm and I drop the temperature down to 17.5°c and the fan to 1 or 2 and that seems to work nicely for me. I always make good use of the heated steering wheel, if your hands are warm then the rest of you is warm and toasty.

If it's damp out side (seem like very day at the moment) even with the rear heated window on it doesn't get rid of all the moisture on the rear screen, so I reach back and turn on the rear heated seats for a while and that sorts everything out nicely.
 

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I always make good use of the heated steering wheel, if your hands are warm then the rest of you is warm and toasty.
I disagree, I really found holding onto a hot wheel while the rest of the cabin air was cold around me a deeply unpleasant experience.
Like being in a cold room and holding onto a heated towel rail.
I hated it so much that I didn't go for Tekna spec this time around, no point in the heated seats/wheel if I'm heating the cabin.
 

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The heater will give you heat, but the Leaf is a pain for misting and it will mist up easy using heat alone.
Aircon will dehumidify the air and get rid of the mist.
Up to you if you use the aircon 'on demand' to reduce misting as required, I just leave mine on all the time.
I never use auto.
Horses for courses and all that. I'm very new, but have had some quite inhospitable conditions already. Auto all the way - temp set to 18C, and if the window is steamed up I push the front window button on the right hand side in the photo above. It clears the window very quickly, and as soon as it has done I push the auto button and leave that for the rest of the journey.
 

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Misting was a big problem in the Leaf 1, but I never had the problem in the current model. Not 100% sure of this, but I believe the Leaf has two heat pump circuits, one for heating and one for cooling.
 

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I’ve had my Leaf for two years and still haven’t figured out how to keep a constant temperature. It’s either blowing hot air or cold air.
 

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Mine has heat pump too.
We must have different definitions of climate control working perfectly, as I rate it as very poor.
Always needs to seem fiddled with, whereas other cars can just be left to get on with it.
I don't know why.
I never had to tinker with mine other than to reduce the power consumption to gain a few more miles when necessary.
 

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I don't know why.
I never had to tinker with mine other than to reduce the power consumption to gain a few more miles when necessary.
Well, I'll give you one example of how it works completely differently from other cars.
If you use Auto, the aircon goes off.
If you press aircon, auto goes off.
That's not happened in any other car I've had, you can use auto and aircon at the same time, it's not an either/or in other cars.
 

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Well, I'll give you one example of how it works completely differently from other cars.
If you use Auto, the aircon goes off.
If you press aircon, auto goes off.
That's not happened in any other car I've had, you can use auto and aircon at the same time, it's not an either/or in other cars.
On some cars, the auto mode will switch the A/C off if the humidity is low. It comes on again if, for example, you drive through rain.

I can't remember how my Leaf behaved although it didn't usually need the A/C to keep the screen and windows clear, warm air did the job.

A/C was only used in hot weather.
 

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On some cars, the auto mode will switch the A/C off if the humidity is low. It comes on again if, for example, you drive through rain.

I can't remember how my Leaf behaved although it didn't usually need the A/C to keep the screen and windows clear, warm air did the job.

A/C was only used in hot weather.
I've not come across another car that does this, not one.
I could give you the list of cars I've had, it's fearsome (I get bored of cars easily).
On every single other car I've had, auto and aircon could be used at the same time and it would stay on all the time.
Aircon is a 24/7 feature for me, never off.
 
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