Climate Control

[kmc]

Hi there. Just signed up as previously visited as a guest to read up on the Octavia but I've now finally took the plunge and I'm going to be picking up my 'new' 2nd hand Octavia on Saturday - it's a 55 Elegance 1.9TDI. I'm hoping that it's going to be a good reliable car!!!
Anyway, I have a question about the climate control which I hope somebody can advise me on: is it possible to have the ventilation system on without the air con but still set to auto so that the system adjusts for the set temperature? I have this feature on my current Pug 306 - even without the a/c on, the fan speed varies until the temperature I set has been reached.
Thanks in advance for any advice! It's much appreciated.

[Scottiepaul]

Well done - I hope its reliable to. No reason why it shouldn't be. Not sure if your car has climatronic or dual zone, however either way it should have an ECON button. With this set on and AUTO on it switches off the air con compressor. Remember to run it every now and again to keep the compressor lubricated, esspecially through the winter. Hope this helps.

[mluton]

Im sure its on all the time, but there is a switch mod on here somewhere.

EDIT:Here it is:
http://www.briskoda.net/forums/octav...atronic/63652/

[runboy]

If I've understood you right, you mean can you adjust the climate temp to, say, 17c in warm weather and will the fans speed up so you have more air blowing from the vents, but the aircon isn't actually on so you are not getting icy air from the vents?

If so I think the answer is yes!

I have my climate set to auto, and the Econ light is on meaning the aircon is running at its lowest level e.g. the compressor is off or at the lowest it will go (I did read that most VW climate units operate at the lowest 3% aircon to keep the system running - the old "use it or loose it" issue). When I set the temp really low the fans will kick up a gear so it's like having your fan on at work - the air is cooler becuase its moving quicker but it isn't artificially chilled.

[kmc]

Many thanks to everyone who's taken their time to answer my question - in answer to runboy - yes, you're right, I want the system to auto regulate the temperature of the cabin but without the actual a/c on in order to keep the fuel economy good. However, as you point out and from reading some other threads, it seems that the a/c may not actually ever be switched off fully. That's okay. I know now! The car I'm getting is an Elegance so it is the 2 zone electronic climate control. Looking forward to it - wished I had the MP3 stream though but buying 2nd hand you can't be choosy although the 6+1 CD changer should help things!!

Originally Posted by runboy

If I've understood you right, you mean can you adjust the climate temp to, say, 17c in warm weather and will the fans speed up so you have more air blowing from the vents, but the aircon isn't actually on so you are not getting icy air from the vents?

If so I think the answer is yes!

I have my climate set to auto, and the Econ light is on meaning the aircon is running at its lowest level e.g. the compressor is off or at the lowest it will go (I did read that most VW climate units operate at the lowest 3% aircon to keep the system running - the old "use it or loose it" issue). When I set the temp really low the fans will kick up a gear so it's like having your fan on at work - the air is cooler becuase its moving quicker but it isn't artificially chilled.

[dstev2000]

Press AUTO then press ECON.

Job done

[Niall]

Just Drive!

I leave the Climate Control on Auto in my Mk 1 and only ever adjust the temperature and let the system do the rest. I have no noticeable economy drawback.

I thought the whole point of Climate Control was that unlike more simple A/C systems which where either on or off, it was a bit cleverer than that so that the compressor wasn't always going flat out? Anyway, in the winter the dehumidifying/screen clearing benefits of A/C are just as important as being comfortable in summer.

Niall

[mluton]

Originally Posted by Niall

Just Drive!

I leave the Climate Control on Auto in my Mk 1 and only ever adjust the temperature and let the system do the rest. I have no noticeable economy drawback.

I thought the whole point of Climate Control was that unlike more simple A/C systems which where either on or off, it was a bit cleverer than that so that the compressor wasn't always going flat out? Anyway, in the winter the dehumidifying/screen clearing benefits of A/C are just as important as being comfortable in summer.

Niall

Same here.

[cheezemonkhai]

Originally Posted by mluton

Im sure its on all the time, but there is a switch mod on here somewhere.

EDIT:Here it is:
http://www.briskoda.net/forums/octav...atronic/63652/

No on the MK I Octy Elegance the air con is on a clutch (that can fall off, but do a search on that) and when you hit the ECON button the aircon is actually off.

Auto or nothing means it is on.

[mannyo]

The fuel economy is unaffected with the aircon on auto or econ, its exactly the same. All the button does is stop the aircon running cold air into the cabin. On the octavia II, the aircon compressor is driven all the time so it makes no difference to the economy what setting you use.

[dstev2000]

Originally Posted by mannyo

The fuel economy is unaffected with the aircon on auto or econ, its exactly the same. All the button does is stop the aircon running cold air into the cabin. On the octavia II, the aircon compressor is driven all the time so it makes no difference to the economy what setting you use.

Yes the compressor is driven all the time but the load on the compressor changes depending on the cooling/dehum demands in the cabin via the amount of refrigerant being pumped around the system. It's the equivalent to your engine unloaded on tickover or fully loaded when accelerating up a hill, which is going to use more fuel?

If the compressor was running on load at all times it would eventually freeze the evaporator.

The Octavia II compressor has the advantage of having no clutch to break off but the downside is you are paying via the fuel economy for the internal parts of the compressor to run all the time. The compressor on full load has to steal x horsepower from the engine which means more fuel burnt.

The ECON button therefore has to make a notable difference to fuel consumption.

[cheezemonkhai]

EDIT: Dooh I forgot 55 is a MK II.

[Scottiepaul]

Originally Posted by dstev2000

Yes the compressor is driven all the time but the load on the compressor changes depending on the cooling/dehum demands in the cabin via the amount of refrigerant being pumped around the system. It's the equivalent to your engine unloaded on tickover or fully loaded when accelerating up a hill, which is going to use more fuel?

If the compressor was running on load at all times it would eventually freeze the evaporator.

The Octavia II compressor has the advantage of having no clutch to break off but the downside is you are paying via the fuel economy for the internal parts of the compressor to run all the time. The compressor on full load has to steal x horsepower from the engine which means more fuel burnt.

The ECON button therefore has to make a notable difference to fuel consumption.

Agree 100% I get a couple of extra mpg on my everyday run on ECON and their is a tad more urgency at the upper rev range on my TDI vRS due to the reduced load.