Swapping to new extractor fan (2 wires to 3)

[kebl2825]

Can't tell from the photo - is the jumper piece still in place (bit from instructions that allows you to select slow/medium/fast speed)? And all the obvious that circuit on at CU, isolator on, and switch on that you're using to control the fan?
Are your live and neutral definitely correct way round all the way back through the isolator and switch? And isolator in/out the right way round?

If you want to just test the fan unit and your internal fan wiring connections on their own, you could wire it into a 3A fused plug top rather than (as I've assumed) a feed from the lighting circuit.

 

[Taylortwocities]

Just re check that you have L & N the right way round and that you have a wire link between L & SL

if fan not working after confirming that then take it back for a replacement.