K11 1.4 SE + Air conditioning

Hi can anyone tell me if the aircon radiator fan in the engine bay should start straight away once it’s turned on? The fan works ok in the car the light is on the button when I turn it on I do need to get the A/C regas the engine is on lol
If the ac isnt pressurized the ac wont turn on. The switch does light up because iT is pressed. Doesnt indicate If the ac is working Or not.