Bathroom extractor fan - two wire feed

[actomox]

I am looking to replace a 4" through the wall bathroom extractor fan operated by a pull cord which has become very noisy. I wish to replace it with a similar pull cord operated model but, if possible, with an automatic humidity sensor. However, on inspecting the wiring of the current one, it has only a two wire feed. Are there any recommended models which could be installed which will safely operate on a two wire basis and provide the humidity control function?

 

[DefyG]

Not that I can think of, your best chance would be to convert the switched supply (use existing pull cord switch point as pull cord fan isolator) to a permanent supply and get a fan with an integral pull cord (Perhaps viable as yours is wall mounted)?

 

[actomox]

Thanks. Sorry - I should have mentioned that the existing pull cord operation is integral, not from a ceiling rose

 

[DefyG]

This would do then if you already have permanent L+N at the fan position;

Vent Axia VA100LHP 251610 White Bathroom Unshuttered Axial Fan With Humidistat Pullcord & Neon IPX4 100mm / 4 Inch 240V​