Airconditioning problem

[Nicky]

My D4 MY2015 has aircon problems, doesn't hold the setting, and trails some clean water from underneath.
Does anyone know what the solution is, I suspect the thermostat for the aircon, where in the car does it live?

[DiscoJeffster]

You’re aware air con is meant to leave trails of water yeah? That’s normal?

[Nicky]

You’re aware air con is meant to leave trails of water yeah? That’s normal?

Sure, but after parked, and cold start, maybe the drain, where would that be?

[BobD]

I'm not sure what you mean by doesn't hold the setting but perhaps it is icing up and the ice is melting when you stop for a while.

I would just get an air con specialist to fix it. Diagnosing the fault won't be a problem to them at all.

Since the compressor is variable displacement to vary the air temp it could well be a compressor problem if it doesn't respond to the commands from the ECU properly. I had to replace my compressor last year because it wouldn't start cooling for about 5 to 10 minutes on hot days. It is usually the control valve that is faulty but at over 200,000km the compressor is not far behind so I replaced the whole compressor.

[101RRS]

Yes water pools underneath when the car has stopped, the higher the humidity the bigger the pool of water - all normal.

[matti4556]

Start with the cheap stuff - has the cabin air/pollen filter (behind lower glove box) been replaced?
If its blocked or airflow is reduced, you won't have enough air going across the evaporator to cool down the inside and yes- it may well ice-up and cause pooling after the car is parked up (well more than normal) and even more restriction to airflow. Pull it out completely (the filter that is! [biggrin]) and go for a run to see if there's a change in circumstances - if it fixes the issue, then definitely buy a new filter and put it back in. - Matti