multiple attic fan settings?

I live in southern ontario. I have 4 attic fans on my house I'm wondering if anyone can offer advice on setting the temps. The best way to describe their location is in height I guess. The highest ridge of the house has 2 fans. One on each end. Then there is a fan on a lower ridge but still in the same attic space and the fourth is in the garage. The attic space is only joined by the space between the rafters since there is a divider wall there. This fan is lower in height that the other three.
Thanks