06 Passat A/C sound?

[z3german]

So when I bought my car like 3 years ago the A/C had a LOT left to be desired, sales guy was just like "yup thats just how they are" bought it any ways

Year later car went into service, told them to also check the sound of the radiator fan (it was summer at the time, later I found thats just how loud it is and its no big deal at all.), as well as the A/C, I was like SURE it was way too weak. Came back and they said those 2 things are working normal.

Just last week my mum brought it to a friend who is a mechanic and usually does simple stuff like oil for us, anyways, he apparently filled the refrigerant in the AC unit or something of the sort, and the AC runs so cold now

But now when driving with the AC on there is this weird buzzing/purring sound that was never there before. Is this normal? When I turn the fan off, the sound stops, when I get to a certain RPM (Still cruising, not ripping it) the sound will disappear, but this could be because the engine sounds mask the sound im talking about.

[BrRsn]

In most cars, turning on the AC at low speed (or any speed, in some) = electric fan mounted on radiator or AC condensor starts up. That could be the source of your noise.

[z3german]

Thanks! I googled it and saw some stuff about something with the AC destroying itself internally when searching up clicking noise, but its more a purring so ill just keep enjoying the new cool air

Getting my mechanic friend to check it up later, will update if its something else.

[godwin]

Make sure your mechanic friend is not overpressurising the system and has added oil to it.

[Phil@rise]

that the compressor clutch engaging and disengaging. It wouldnt have done it before because the system had low pressure. There is a sensor that prohibits the pump from being engaged when pressure is too low