Hello folks. So yeah, this is probably a really stupid question but it's bugging me and i need to know.

 

What's the difference between the A/C and AUTO buttons on climate control? The user manual states AUTO will keep the temperature constant and stop the windows misting while the A/C button is described as causing temp and humidity to drop and stop windows misting. Am i a complete idiot for not understanding the difference? Do i need A/C switched on if i want a temperature inside that is lower than ambient temp outside? Do i need to switch it off if i want an inside temp higher than outside?

 

If AUTO keeps the temp constant doesn't that just mean it will either cool or heat depending on what is needed? I feel really stupid but i really don't understand!

A/C button is a literal on/off for the air-conditioning.

 

Auto button turns on the A/C and will adjust all the fan speeds and vents automatically to keep the temperature to the values you set it to.

 

So auto will adjust fans/vent choices by auto all year round.

As above set ac on, select auto and select a temp you like , mine is 20° and leave it to do it’s thing 24/7 365.

Thanks for the quick replies folks. Still a bit confused tbh. I can switch off A/C even though AUTO is switched on though? So what does that do if AUTO is enabled? And if it's switched on but AUTO determines i need heat why does A/C (aka 'cooling') still show switched on?

 

I've been running for ages with both buttons switched on as per Kenny so no real issue as such. Just the nerd in me wanted to understand. I'm still not seeing why it makes sense for both buttons and for both to be independent of each other. It would make sense to me if it were an either/or thing but can't understand how both can be on or off regardless of the state of the other - as in A/C was the manual control for cooling but that meant you weren't in AUTO mode and vice versa. Or if the A/C button showed on or off depending on whether AUTO decided you needed cooling or heating.

 

I'm clearing missing something because i asked a friend on this recently too and they didn't seem to understand my confusion either. Perhaps i am overthinking this!

 

 

Auto just sets the fan speeds and which vents are in use.

 

Adjusting them all depending on what the car can measure interior temperatures and external.

 

 

A/C button is a master override for the air-conditioning system on/off.

 

A/C stops the car from misting up, and humidity getting out of control.  Best left on all year, and operates down to about 4C or 5C, keeping windows clear in winter.

Here is some information from the technical documents describing how things work (SSP's) 

 

 

 

Although I find auto button very good, there will always be someone that thinks they know best, so this is why we have manual settings for fan speed, individual vent controls and of course the A/C on and off (fuel savings)

 

So I guess this is why they are included as some will want the manual control options.

 

As stated in the above images, we humans tend to find 20-22C comfortable zone in the car.

 

I set mine in Auto with AC on all year round, often at 22C, but sometimes 21C.

 

 

Bottom line is if you have Auto, use it, and leave AC on all year too, as it makes the comfort inside the car better.

A/c is air conditioning, not cooling. Many people think that ac is there to make the air cold. There is so much more to it than that.

 

The ac will clean the air, cool the air, remove moisture and particles from the air, only once this is done will it then heat the air if required.

 

so ac should be on all the time really - no reason to turn it off. 
 

auto is for temperature and direction control.

 

ac is for conditioning the air.

Ah ok, i think i understand now. Thanks varooom!

 

So if i've got this right, if i had AUTO enabled but A/C switched off then it's possible the temperature might never get cool enough on a hot day because AUTO can only control air vents/fan speed but wouldn't actively cool the air, is that right?

 

And if i've got this right, then although having A/C enabled on a cold day doesn't stop the air being routed via heating elements, it's still useful because of the dehumidifying effect of the A/C unit?

 

I guess then there's an argument that it makes sense being able to switch off A/C on cooler days as you're basically wasting energy cooling air only for it to be heated before the vent and unless misting up is an issue that seems wasteful.

 

I think it all makes sense to me now - thanks!

 

 

1 minute ago, greycloud said:

Ah ok, i think i understand now. Thanks varooom!

 

So if i've got this right, if i had AUTO enabled but A/C switched off then it's possible the temperature might never get cool enough on a hot day because AUTO can only control air vents/fan speed but wouldn't actively cool the air, is that right?

 

And if i've got this right, then although having A/C enabled on a cold day doesn't stop the air being routed via heating elements, it's still useful because of the dehumidifying effect of the A/C unit?

 

I guess then there's an argument that it makes sense being able to switch off A/C on cooler days as you're basically wasting energy cooling air only for it to be heated before the vent and unless misting up is an issue that seems wasteful.

 

I think it all makes sense to me now - thanks!

Yup on a hot day, with AC off and auto on the car will push the fan speeds up and try to direct more towards the face/body.  It will never make you feel cool, like putting your face into an oven because there is no active cooling.

 

On a cold day the heated air will pass through the AC radiator and suck the excess moisture from the air (as it does in Summer) the Windows will be clear from misting, and also dryer air feels better to our skin also.

 

On a cooler day as mentioned the drying effect stops the car misting up, and we feel more comfortable with less humidity in the air.  Cold and high humidity feels awful, and it can be colder with less humidity and feel better as damp air wicks away body temperature.

 

Run your A/C 24/7 365.

It will keep you feeling better, keep moisture out of car and smells (mould loves damp, hates the dry)

 

Also, the A/C doesn't operate all the time, it turns on and off, as needed, so doesn't suck engine power as much in the Winter.  So any perceived fuel saving won't really be felt too much.

 

Also, having had a car where I turned off A/C for month's at a time, I killed the compressor (forgot to operate it at least once a month)

That cannot happen on a VAG engine from the last 15 years using the clutchless modulating valve system, when AC is turned off there is still a minimum circulation of refrigerant.

6 hours ago, varooom said:

dryer air feels better to our skin also.

 

Not to me buddy, I get through enough Nivea as it is (and yes I'm a bloke)!

Just now, Gax said:

 

Not to me buddy, I get through enough Nivea as it is (and yes I'm a bloke)!

You must be one of the lizard people 🤣

Jokes aside, I mean more from a cold feel.

 

0C in UK damp weather feels worse than -20C in drier climates to some people (I think I'd die mind you at those temps.