Holden Barina XC 2002 air conditioner hot air

Hello to everyone.

I bought a second hand Barina (Corsa C) and everything was fine.
Days ago during one of those hot days my car was parked outside, I started it as usual and turned the air conditioner on.
After a while I realised that there was only hot air coming from the dash board so the air conditioner is not working anymore.

Could anyone please advice me what are the basic steps to understand if it could be just a faulty fuse (I hope) or something which will require a specialised mechanic?

Thanks in advance.

Have a look at the AC pulley while the car is running, while the AC is off the clutch won't be engaged so while the belt and pulley will be turning, the AC shaft won't be. Turn the AC on and if the fuse is working correctly it will engage the clutch so when yuou look at it again the AC shaft should be turning with the pulley. If the fuse is blown and the clutch isn't engaging you'll also notice there's no drop in engine rpm when you turn the AC on.
If it was working fine before the other day then the fuse is your most likely bet, if you haven't used it for a while then it could be out of gas or something wrong with the compressor. If it's the fuse then there is a How To on changing it yourself if you're semi-mechanically minded.