Climate control set to low blowing hot air?

K

Karlbar2k

Member
Any idea where to start? Recently changed the thermostat and the engine temp sensor but not sure if that's got anything to do with it.
 
The title is not too clear but I'm guessing that with the CC set on cold, it's still blowing hot.

Motorised flaps under the dash control the blending of air from the heater matrix and aircon evaporator core and distribution of the blended air to the various vents in the dash and footwells. Its possible the air blending flaps are not working correctly and are stopping cool air entering the cabin.
Sometimes cycling the flaps can help - change temp from coldest to hottest setting several times and do the same with the windscreen defrost and fotwell control buttons.
If you have access to VagCom you can check for fault codes and cycle the flaps in diagnostic mode

Cheers Spike
 
Hi Spike,
I have a similar problem on my A2 blowing hot air, I do have a replacement air flap control motor but haven't a clue how to access behind cc unit!
Is it possible it could be a temperature sensor as well?, because this fault is intermittent and was working perfectly throughout the summer but it's temperamental again now!
Have tried what you suggest including disconnecting battery for a while and it's so frustrating!!!!
Cheers,
David
 
Hi one other thing to check is that the fan on the radiator is working as this is used all the time to cool the refrigerant. Easy to check by removing the bonnet and turning the key with the cc switched on and you will see the radiator fan start running at a reduced speed. If the fan doesn't run then you have a failed fan or the fan controller-in our case it was the controller(large alloy casing with two big wiring connections to the side of the rad)
Hope that helps mike
 
have experienced this on 2 A2s I have owned and it really does blow out hot air, so mine was not related to the air con at all.

The heat was very uncomfortable.

I used to try cycling the temperature but that never worked.

But then you would get in the car the next day and it was working fine.

It didn't do it too often and so we just put up with it rather than spend a lot of money "chasing" the fault.

This one may be different and as Mike has said checking the fan is easy so it is well worth checking that.

Steve B
 
Did anyone/ Karlbar actually get to the bottom of this? Just had thermostat and the engine temp sensor changed afew weeks ago and fault started soon after. Intermittent blowing hot even on Low/cool!
 
Birty said:
Did anyone/ Karlbar actually get to the bottom of this? Just had thermostat and the engine temp sensor changed afew weeks ago and fault started soon after. Intermittent blowing hot even on Low/cool!
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This is fairly common. It's happened with mine on and off for a while. A scan is showing a faulty sensor in the climate system. Hopefully getting this sorted in the next few weeks so I will post details of the fix. My display on the climate panel now has a shadow image of an impeller behind the temperature display which is new.

The system still cycles fine between the various vents when you 'exercise' them manually however it's not blowing as cold as it should. The compressor was recently recharged and showing no leaks.
i
 
murdo said:
This is fairly common. It's happened with mine on and off for a while. A scan is showing a faulty sensor in the climate system. Hopefully getting this sorted in the next few weeks so I will post details of the fix. My display on the climate panel now has a shadow image of an impeller behind the temperature display which is new.

The system still cycles fine between the various vents when you 'exercise' them manually however it's not blowing as cold as it should. The compressor was recently recharged and showing no leaks.
i
Click to expand...

Mine blew hot all the time this morning Murdo on the way to Lancaster. Tom plugged in his laptop, "massaged the flaps," and its working fine again now although it was showing the usual temp sensor fault. :)
 
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the flap massage can help reset (go into the HVAC in VCDS, block 001, hit go) the end points of the pots, but it can't fix overly worn ones. It's partly sorted my issues but I still don't get warm air up onto the screen after half an hour or so, which implies my central flap motor needs changing (again!).

- Bret
 
Birty said:
Behaved ever since it did it the once! Will leave alone I think...
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If it was a one-off, it may be a sign that the vanes may be getting sticky. Run it from 'low' to 'high' and back a couple of times, at intervals (say weekly or monthly) just to make sure it stays free and doesn't stick again.
 
Just to update. Just had the a2 back after long term loan to daughter and it was still blowing hot. VCDS reset all codes after doing a full scan and a.c. is working again.
 
Karlbar2k said:
Just to update. Just had the a2 back after long term loan to daughter and it was still blowing hot. VCDS reset all codes after doing a full scan and a.c. is working again.
Click to expand...
I had this with mine and it was poor connections to the flap motors under the dash. It was as simple as unplug them and plug in a few times followed by a drop of WD40 on the contacts before final reassembly.
I think there’s a guide on here somewhere!
 
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