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Does anyone else have this problem?
Usually if the fans are blowing above half/normal I get a whistling sound that increases with fan speed if the air con is on (not sure if it does it with just the fan).

Don't recall it making this noise when new and it's getting on my nerves!
 

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I only get more noise if the vents aren't open enough to let all the extra air out. I sometimes find that my wife has closed a vent or two��
 

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Yep, the whistle is a biggie for me too. Also a foul smell shortly after switching the aircon off. I have spoken to the dealer and on the next visit (changing the door seals for the third time) they are going to do 'an aircon bomb' which they believe will help. It apparently 'flushes' the system. They assure me that the pollen filter was changed at 25k service!
 

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Yep, the whistle is a biggie for me too. Also a foul smell shortly after switching the aircon off. I have spoken to the dealer and on the next visit (changing the door seals for the third time) they are going to do 'an aircon bomb' which they believe will help. It apparently 'flushes' the system. They assure me that the pollen filter was changed at 25k service!
The smell is from mould/bacteria/growth (I dont know what exactly!) growing on the nice moist bits of the heating system left the aircon pulling the moisture out of the air... you can get aerosol cans of disinfectant/nicer smelling stuff that are squirted into the vents (inlet vents) that can clean this out I understand. Or - leave it to run without the AC on hot dry days for a good while and let it dry out thoroughly. IIRC changing the pollen filter can also help this..
 

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As motmot adviced, the key here is to dry the evaporator of the ac. I try to explain how and why this should be done. As a part of the air conditioning process the ac system develops moisture on a part called "evaporator" - or that's what it's called in Finnish (not sure of the exact term in English). My method is to shut down AC and turn manually the blower to high few kilometers before arriving to destination thus allowing the system to dry from moisture. If the unit is left moist, dust and other impurities can collect on the evaporator and mold and bacteria may develop. Smell is a sign of impurities in the airing system or more specifically on the evaporator.

Drying the system keeps it healthy and fresh. If it develops smell, a special aerosol cleaning solution can help. Ac in my old car, which my lovely V40 eventually replaced, had developed a smelly and unpleasant problem with the ac. I bought an aerosol disinfect solution from a local parts shop, followed the instructions and voilá the system was clean and smell gone. As a result I learned to always allow the ac to dry before arrival.

So when you are lets say 2-5 km from your destination switch the ac off. If it's been hot and/or humid, you can smell and feel moist air coming from the wents after shutting the ac-function off. This is completely normal and then the moisture is drying nicely. :)
 
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I have the same problem, but also bad smell comes when AC is blowing. Noise is a sign that the AC Compressor is beginning to go bad, a buzzing noise may be heard when turning the AC on. This is usually the sign of an overcharged system, which is only usually an issue when too much Freon is added during an air conditioner service. An overcharged air conditioner will not properly cool and needs to be taken care of as soon as possible. I am working at aircon servicing and I have seen many such problems.
 

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I had the same issue as well. I was trying to solve the problem by myself because the noise was annoying the heck out of me. I read up on some air con servicing articles that there could be something stuck in the vent and I went to check it out and it was indeed some dead insects and leaves in it. I was puzzled as I have never eaten any food in my car or whatsoever but whatever the case it is finally solved now and my air con does not make any sounds.
 

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I had that after I had my car's service done. It whistled (like leaking air) when fan was high but I removed the air cabin filter (which they changed) and it turned out to be inserted a bit wrong so I took it out, put it back in correctly and the noise went away. The air cabin filter is easily accesible behind the head unit from the passenger´s side (LHD, I'm not sure about RHD)
 
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