Hi,

We have a 2008 1.8 petrol S40 and the AC is very tempremental. Sometimes the AC will turn on fine and blow out cold air, but then you can't get hot air again when you turn it off, and then when you do get the hot air, it takes a million attempts, usually very randomly to get the AC to switch on again and blow out cold air. When it does turn on, the air is cold and working correctly, but when it's not, the temp is quite warm.

Another thing it's doing is it doesn't blow air out of the vent you select. So rather than feet, it may blow out of the window vent, and then instead of blowing out of the entire window vent, it'll only blow out of the drivers side and not the passenger side.
Someone mentioned it being some sort of control unit or something? but didn't give an exact name or part number.

Any help or suggestions welcome, thanks

 

It's not clear what "hot air" you're not getting. The common thing with Volvo A/Cs being intermittent is that the compressor clutch is worn and can't QUITE pull in to engage the compressor. Turn on your A/C and check it when it's not blowing cold, and see if the clutch is engaged (if it is, the entire compressor pulley/clutch mechanism will be rotating - if the clutch isn't pulling in, only the front part will be rotating). If you're brave (and it's accessible) you can tap the pulley and see if the clutch pulls in. If this is the case, just search for compressor clutch threads, and you'll see how to fix it (it's not difficult or expensive on most vehicles - I fixed my 2001 V70 with three short lengths of wire that held the front plate a couple mm closer to the clutch's magnet).

There's a mode controller that sets where the air goes, but I have no clue about where yours is (since you folk all sit on the wrong side of your car to drive it). ;-) Should be able to look up threads on the subject though.

 

So.. basically when you have the AC on, we end up with sometimes getting hot air coming out of one half of the car and cold air out of the other side, sometimes it's all hot, othertimes it's all cold as it should be. Never get any air coming out of the vents for the feet either at all.

It's like a mix of this mode controller and maybe the compressor? Unless the controller also affects the compressor at all? Do you have a part number at all as I have done a search for this thing and can't find anything on this forum or anything on google?