Ventilation machine

[SQLit]

Since it is impossible to know what exactly what your talking about or what country your from, how about restating the question with some specifics?

[Speedy Jim]

Do this GOOGLE search:

Installing a complete new one on a roof can be difficult because of the shingles. You may be able to find a new motor for the existing one and repair that way.

Jim

[John]

I'm looking for a ventilation machine or whatever it's called, english is not my first language.

Are there any models one can install yourself? I've got one on my roof but is broke down and I want to install a new one to replace it.