Would like: 4-hr count down timer
In the summer, i'd like to run my fan for the first 4 hours of the night. After that the rooms cools down enough where I don't need a fan. I've searched everywhere and cannot find a cheap 4-hr countdown timer. I have found some for $50, but that is outrageous. I cannot modify a mechanical kitchen timer because those are only 1 hour.
So, does anyone have any ideas to make a 4-hr countdown timer that turns on a 110v circuit for 4 hours, then turns it off and leaves it off?
Forgot to mention. I go to bed at different times so a regular on/off timer would not be optimal here.