Replacing A flexible Hose on extraction fan

[tonysg7uk]

Hi
I need to replace a flexible hose leading from the downstairs toilet to the outside wall.
Is there a simple way of doing this, like being able to pass the new hose through the exisiting hose so that it ends up in the right place. If so, is there anything available on the market?
Thanks in advance
Tony

 

[Nige F]

don`t think so - you could pass a hose through a piece of soil pipe - but not hose/hose