Attic Fan With Separate Automatic and Always On Settings

[W]

I am looking for a gable attic fan that can be wired to a wall switch and has three modes:

1) Always on

2) Automatic on depending on inside temperature reaching some threshold.

3) Always off

Ideally I would like to have the wall switch have three positions that correspond to these three modes.

Does anyone know of a product that handles this application off the shelf?

[Steve]

yes