Anyone have the schematic for this or can tell me how to wire it? On the toggle side I have B/W/Grd and on the timer side B/W

 

This Timer is not a good, workable, type of Accessory / Control for an Attic-Fan.

The Timer You have shown is outdated and no longer sold by Dayton-Products.

You need a simple Line-Voltage Thermostat.
You also need a low-RPM Fan ( not a Blower ) specifically designed for Attic-Fan-Duty.
They usually come packaged in the same Box.
Common HVAC style Blowers will usually burn-up the Motor when placed in an Attic.

A higher-quality, more expensive, Attic-Fan can be purchased from
Grainger-Industrial-Supply
or
McMaster-Carr-Industrial-Supply.

A cheaper, "Consumer-Grade"-Attic-Fan can be had from Home-Depot, or Lowes, etc..
Consumer-Grade Attic-Fans normally come with a built-in Thermostat.

There are several different styles to suit different Home-construction-circumstances.

An Attic-Fan generally won't lower your Electric-Bill,
but it may keep the interior of the House more comfortable during the Summer-Months.
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It was already installed when we purchased the home. I'm not so concerned about the timer as I am just getting the unit wired back so I can operate it. It does make the house comfortable this time of year and is more efficient than the AC unit (also original to the home).

 

Those are normally called a "Whole-House-Fan".

A Heavy-Duty, 20-Amp Light-Switch is all You should need. ( ~$5.oo to ~$10.oo )
A 15-Amp Light-Switch will not last very long.

Just turn it on and off manually, no need for an expensive Timer or Thermostat.

Do not attempt to mess with the Wiring if You do not have substantial Home-Wiring-Experience.

Pay for an Electrician.
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