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THIS IS GONNA SOUND REALLY STUPID BUT MY MATE JUST ASKED ME WHY IV BEEN DRIVING AROUND WITHOUT THE ECON MODE i.e OFF...NO WONDER ITS KILLING MY FUEL, HE SAID I SHOULD ALWAYS TRY N KEEP THE BUTTON ON OTHERWISE THE COMPRESSOR IS ALWAYS ON PUTTING STRAIN ON ENGINE AND GIVING POOR MPG, SAVES FUEL AND BETTER PERFORMANCE??? I NEED A FULL LOWDOWN WHEN SHOULD I USE AUTO/ECON, BEST TEMP ETC

CHEERS
 

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ECON means aircon compressor is 100% off

AUTO means the aircon compressor is on, and the climate control will be
trying it's best to maintain a constant cabin temperature to the one
that you've set. On Auto the fan speed and air direction is
automatically adjusted by the climate control to where 'it' thinks is
best.

If u manually alter the fan speed or direction of airflow, then the
'AUTO' icon disappears, but the aircon compressor is still engaged and
running.
 

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I have mine on AUTO around 90% of the time i am in the car.  Usually around 22 degrees.  It works perfectly and always has done.  Fuel economy is still good as its a TDI.
 

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On Auto the fan speed and air direction is automatically adjusted by the climate control to where 'it' thinks is best.
I must disagree, when set to auto mine does not change the air direction it always comes from vents in the dash.

unless theres somthing wrong with mine.
 

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I leave mine an AUTO all the time, and just change the temperature to suit what I want.

Only time I change is when I use the screen demist button, or when I manually turn up the fan speed to maximum - you're supposed to run it at this for a few minutes every week or so...it says in the manual somewhere.

I was always of the mind that it's best to just leave it on, as if its off for a long time the compressor motor can sieze? The dealer I got mine from recommended me to keep it on too, and if I turned it off, not to leave it off for long.
 

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Mine gets changed from auto to econ quite a bit. Don't think it really makes a huge difference to mpg, especially in a diesel.
 

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I leave mine on auto all the time - just easier. I find it's a pain to have the demist button on the air-con unit though - very fiddly to turn off while you're moving once the windscreen has cleared.
 

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Mine is on ECON mode most of the time as switching it off or changing it to AUTO will turn on the compressor and cause greater fuel consumption, slower acceleration and more strain on the engine. However, I agree with earlier comments that's not wise to leave in ECON mode for too long else the compressor could seize up. So I occasionally use it for demisting the windscreen during winter months. In summer, the air con is on most of the time (I live in the south) so the compressor gets a good run during those times.

~ Maxie
 

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Mine gets changed from auto to econ quite a bit. Don't think it really makes a huge difference to mpg, especially in a diesel.
Yup!! Found more of a difference on my Petrol Passat (with climate). But my Golf only has air con [:(]
 

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it depends whether you are running in ECON as well. At the moment, i tend to drive round with the demist on, but also with ECON showing. this way you have the fans directed at the windscreen, but without the compressor running. And i didn't think the compressor worked below 4 degrees c anyway?
 

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Oh cheers for that .......in the one year i have owned my motor i have never had it set to econ

i shall be switching it over to that from now ..........[;)]
 

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Regardless of whether you have basic a/c or full climate control you should run the compressor for at least 20 minutes a week to lubricate the system. And you also should run the heating on full to clear the vent ducts of any moisture which may have formed whilst running the system. If you don't run the system it will seize up and you have the ?800 odd bill to replace the system. You can't recoup the cost of replacement (both environmental and monetary) through improved mpg by not running the system.

If you are getting very poor mpg there is likely to be another cause other than just running the a/c / climate. Running the a/c doesn't affect my petrol Bora significantly, maybe 1-2mpg at most. She still returns in the mid 30's.

On climate control the Econ setting turns OFF the compressor and thus means you are running regular heating and ventillation of a car with no a/c system. Therfore you are not using the system and it is not being lubed ([:O]). The idea of climate control is to maintain a set temperature within the car. Sometimes this means heating the car and sometimes it means chilling the car. If you have the Econ button on then the climate is not going to run properly.

Of course for any of this to work you need to turn on the climate (or turn on the vent fans for a/c cars) in the first place. If it is not on then the compressor won't be running.
 

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Interesting reading this, other than occasionally switching the Windscreen demister on (and having it on full speed cold in the height of summer, all 2 days of it) mine is on 19 Deg AUTO and has been since i picked up from the garage new 4 years ago. I have just had the air con serviced and all fine except needing a bit of gas. I can't see the point in paying for Climate then using it in ECON.
 

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Regardless of whether you have basic a/c or full climate control you should run the compressor for at least 20 minutes a week to lubricate the system. And you also should run the heating on full to clear the vent ducts of any moisture which may have formed whilst running the system. If you don't run the system it will seize up and you have the ?800 odd bill to replace the system. You can't recoup the cost of replacement (both environmental and monetary) through improved mpg by not running the system.

If you are getting very poor mpg there is likely to be another cause other than just running the a/c / climate. Running the a/c doesn't affect my petrol Bora significantly, maybe 1-2mpg at most. She still returns in the mid 30's.

On climate control the Econ setting turns OFF the compressor and thus means you are running regular heating and ventillation of a car with no a/c system. Therfore you are not using the system and it is not being lubed ([:O]). The idea of climate control is to maintain a set temperature within the car. Sometimes this means heating the car and sometimes it means chilling the car. If you have the Econ button on then the climate is not going to run properly.

Of course for any of this to work you need to turn on the climate (or turn on the vent fans for a/c cars) in the first place. If it is not on then the compressor won't be running.
Excellent, very well expressed!
I run my a/c switched on ALL the time in the Golf and the cc in the BMW is always on too, the system will determine whether to engage the compressor or not and because it's 'always on' the demist is helped by the drier air from the a/c system.

The key thing to remember is - you will suffer more from a failed cc/ac system than you would gain in economy from switching it off. I say, when you have a system in the car(climate control) that is designed to keep the temperature stable through all external conditions why switch it off?
 

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I forgot to mention in my last post something I have noticed about modern cars with a/c or c/c. Most of the cars I see broken down in the height of summer (on motorway journeys) appear to have large pools of liquid under them!

This is the first car in which I have ac. Ac is great, and I would consider it a must for my next car, but I will always keep an eye on the water gauge during summer, especially whilst sitting in traffic.
 

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I forgot to mention in my last post something I have noticed about modern cars with a/c or c/c. Most of the cars I see broken down in the height of summer (on motorway journeys) appear to have large pools of liquid under them!

This is the first car in which I have ac. Ac is great, and I would consider it a must for my next car, but I will always keep an eye on the water gauge during summer, especially whilst sitting in traffic.
Broken down car might that you mentioned might have lost thier coolant and overheated.

But in traffic pools of water can be from the air con unit and simply condenced water from the surrounding air. If you touch the pipes in the engine when the air con is on they are seriously cold, but then the condencer is turning the liquid refrigerant into gas.
 

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Admit to turning my climate off when pulling up to red lights [;)]

I read somewhere that running the climate can drain up to 10% bhp. Not sure how true this is but you can definately feel/hear the strain put on the engine at tickover if you switch between Auto and Econ.

Would definately not be without it on really hot days though!

I can't see the point in paying for Climate then using it in ECON.
LOL

Unless u like racing around everywhere ;)
 
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