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My audi A4 2007 A/C does not work, so how can I get cool air in the car? Its mostly 23-27 deg C in the car. All the flaps/motors etc seem to work,or i can disconnect them.
On VCDS The G65 (ambient temp sensor, behind the bumper?) sensor shows High pressure signal too low-intermittent. Thats because there is no gas in the aircon, isnt it. Also I get a reading from Dash Panel Temp, which varies, so that part works. Therefore disconnecting the G65 may allow cool air in?
But really i doubt that will do anything, I think i checked everything else but nothing fixed it.
I cant fix the A/C today and need cool air or I'll have to drive up the motorway with windows open all weekend. Anyone know how the system works?
Thats because there is no gas in the aircon, isnt it
..which is where I would start. Re-gas I think
me too, but as i cant do that yet I need to use the fan side of the heater to try to get cool air
Not really a 'get it sorted today' answer but get the A/C system tested for leaks. On a car of that age probably the A/C condenser radiator thingy has been pelted with stones and split.
alric
I need to use the fan side of the heater to try to get cool air
It'll only every be able to pull in air at whatever temp it is outside. Most of the UK south of the midlands is ~23deg C today, so I am not sure you can achieve much cooler than that assuming you are in that region of the country.
With the a/c system it could be a multitude of things. Re-gas sometimes works, but frequently won't last long if there are other issues, such as leaking seals or a hole in the condensor.
Or it could be the compressor and/or compressor clutch has packed up. This was quite a common failure on older VAG cars (and perhaps still is). I had to fit a new compressor to my 03 Ibiza when the climate control stopped working. A re-gas would not have fixed it.
It’ll only every be able to pull in air at whatever temp it is outside
I was hoping the fan/ speed of the car would reduce the outside temperature, and so a flap must be blocking it
My last two Audi's have had AC problems and a I found that if you open slightly the front passenger window and the same with the rear drivers side window then you get a good crossflow of air through the car.
Not as good as AC but better than having the windows fully down and being unable to hear anything
Are you getting any airflow through the vents at all with the ac set to econ?
Technically a fan actually increases the air temperature. However, movement of air across the skin can increase evaporation of sweat and the cooling effect, but only up to a point. As others have said, if the air outside is warm to begin with, probably getting warmer as it passes by the engine, the cooling effect inside will be fairly minimal. AC works because it dries out the air as well as chills, having a double cooling effect.
yes i get airflo, plenty, its just too warm
The air will be warm, it's warm outside. Windows and more airflow.
Fans move air, they don't magically cool air.
Buy a bag of ice cubes and mount them behind your radiator, if you want them to last longer pack your scuttle panel with them.
And the indicators are set to ‘Lo’, ie the lowest setting not just 18 or something that would be nice if the AC was working?
yes set to LO
ive disconnected some flaps now so's to get the best through flow always
I cant believe I need the aircon to keep it below 26deg
I never had aircon (in my cars)before, it was never this bad
What do think cools the air without air con?
Confused. The fans work, but the air's not cold? So the AC is not working. AC being the bit that cools the air. As above, they frequently leak because stones hit the condenser on the front and puncture it.
However, they also gradually leak and the performance gets worse until the pressure is low then it shuts off to protect it. So it may not be completely empty.
You can take it to Kwik Fit for a re-gas, but that won't work if there is a big puncture in it. But it might work if it has only been leaking a bit. You can also re-gas it yourself by buying stuff from Halfords and a tool - but you need to have the compressor running do it (IIRC) and if there's no pressure the compressor won't run. Not sure how Kwik Fit get around that. They may not do it if it won't run at all.
But as said, if there's a puncture you'll be putting in gas for it all to leak straight out.
strangly enough, all my previous cars without aircon, relied on the fan to keep them cool
Our Aircon broke a whole back and we boiled in it. It has a huge sloping windscreen so we were sitting under glass. Older cars don't have massive windscreens like newer ones.
What do think cools the air without air con?
Entropy
My Audi was the same
The compressor broke - after this the air coming through the vents was much warmer than ambient - I guess the air travels through the same matrix which has ambient heat from the engine of the air con is not cooling.
It might have been that the VAG engineers of the time thought the ac would always work (despite the ‘Lo’) so there was a degree of constant warm flow through the matrix to allow blending of temperature, dunno, guessing now.
edit: just to be clear OP, are you saying that the vent air is warmer than ambient or air coming through the windows?
Ahh something I may possibly be able to help with. So I bought a 2014 plate A3 in the summer a few years ago, asked them to make sure the air con was working. No issues, came to winter and one side wouldn’t warm up at all!
So to fix this it was Audi that replaced the flap motor under warranty, only issue was the part was £70 and the bill was over £1000 as it needed the full dashboard out! So it’s possibly the fan motor stopping the AC working I wonder?
Not sure if it works the same for cold as well as heat but just thought I’d mention it
Non of my cars with AC have ever given cold air through vents when AC is turned off but fan is on.
All of my cars without AC fitted have given cold air.
Difference being one lot of air does a tour of the engine bay in most set ups. And the other feeds from the inlet to the fan feeds direct.
Kwik fit will check system is leak free before re-gasing. So free check !!
Yeah as above the air was really warm from our car when the AC was broken. It maybe some technical reason - warming then cooling to reduce moisture or something, or the other way round - but it may also be something like they didn't bother to keep the path short or out of the way of engine bay or something.
The Merc has a water trap duct that goes into and out of the engine bay, that might get pretty warm. (At least that's what I assume it is)