Should I leave the air con on my car on all the time? My local garage says its better to leave it on because the system is lubricated etc.and less likely to lose gas or breakdown.

Depends on how you feel!

I know that sometimes I prefer to have fresh air via the window other times (very hot days) I prefer to use the air con.

That's why they provide you with an Off button so you can choose

Either way it's going to cost you fuel!

Edited 24 February, 201016 yr by Evening Star

Should I leave the air con on my car on all the time? My local garage says its better to leave it on because the system is lubricated etc.and less likely to lose gas or breakdown.

Your local garage is correct, the system is full of gas when not in use and when it opperates it changes into a liquid, the system has a lubricating oil known as pag oil which when working lubricates the seals and creates a gass tight seal, so if the system is not used the seal become dry and you loose the gas. you dont have to keep it on all the time we reccommend running the system up once a week for a good hour ie when driving and you should be ok. i leave mine on all the time but its personal choice and your mpg will suffer a little if you leave it on.

Leave it on all the time:

Much better for the garages.

Use more fuel

Pollute the atmosphere more.

Get dry eyes, dry mouth and throat too.

or - Run it occasionally, once a week may be quite a lot, I rarely use it and had a prior Octy too, used it the same then, neither have ever had any problem.

I leave mine on AUTO all the time. Tried switching aircon off on ally my recent cars but no discernible difference in indicated mpg.

Car tends to mist up in cold and damp conditions if aircon off .

Every VAG car I have had I have been able to leave it on all the time.

The BMW I had I needed to leave it off mostly as it did dry the air too much.

It needs to be run at least weekly. I too have never noticed an MPG drop with A/C on.

From what I can work out having the AC running causes my car (TDI) to use approx 300mm of additional fuel per hour.

Edited 24 February, 201016 yr by K1W1

With the octy2 the compressor runs whether the aircon is on or off, so fuel savings are almost non existant. I left mine on auto all the time, as a/c not only cools the air but on damp days stops the car misting up. the a/c is only disabled below 4c to stop the system freezing up.

With the octy2 the compressor runs whether the aircon is on or off, so fuel savings are almost non existant. I left mine on auto all the time, as a/c not only cools the air but on damp days stops the car misting up. the a/c is only disabled below 4c to stop the system freezing up.

Could you verify that this is correct?

That running the AC on the Octavia II doesn't use up as much fuel as other cars, if any at all?

Edited 24 February, 201016 yr by foregonereality

That running the AC on the Octavia II doesn't use up as much fuel as other cars, if any at all?

Turn the AC off and on while the vehicle is stationery and watch the fuel consumption on the maxidot go up or down. Turning the AC off improves fuel consumption.

If you're stationary the computer should just show "---"

If you're stationary the computer should just show "---"

but your trip average will drop as you sit there idling using fuel.

Presumably you could measure the rate of that drop.

Edited 25 February, 201016 yr by Phil_P

If you're stationary the computer should just show "---"

According to the manual it should tell you litres per hour when stationary... Must only work when set to metric though as I'm sure mine says ---

And maybe only with Maxidot?

Mine only ever says --- when stationary. No idea how to go "Metric".

What is this "metric" you speak of?

If you're stationary the computer should just show "---"

No it won't. While the vehicle is stationery with the engine running it shows litres/hour in metric or I assume gallons/hour in imperial.

With the octy2 the compressor runs whether the aircon is on or off, so fuel savings are almost non existant. I left mine on auto all the time, as a/c not only cools the air but on damp days stops the car misting up. the a/c is only disabled below 4c to stop the system freezing up.

That's what I thought. Even when it's 'off' that just meant it was 'on' but at a level that didn't actually do any cooling. Just enough to keep things circulating and lubricate the seals.

I just leave it in auto anyway. I've never noticed enough of a difference to worry about.

Not on mine either, when stationery, the instant consumption shows --- only, no figure on there at all.

Must be another "feature" that can be turned on or off.

My car is an Oct 09 build vRS CR.

At idle with the AC on it consumes 0.9L/hour and with the AC off it's 0.6L/hour.

I did test drive an early 09 build pre facelift TDI and that had the same feature on the Maxidot. Our Audi (early 09 build) also displays the same information at idle.

Edit:

I just did some maths. 0.6L = 0.13 imperial gallons so maybe it's too small a number for the car to bother displaying. Another benefit of the metric system I guess. :-)

Edited 25 February, 201016 yr by K1W1