Attic Fan

[pushkins]

I ventured into an attic today to work out why the ceilings in the property were so hot ( NC 90 degrees today) well neither attic fan worked, I placed a thermometer up there while I ran to a big box store to get two new motors and two new thermostats, when I came back the thermometer read....wait for it...... 130 and they wondered why their cooling bills last year were in the $400 + range/month for 1700 sq. feet.

[Hube]

A properly VENTILATED attic will usually get to equal the actual OUTSIDE temperature (perhaps a degree or two higher) but never in the range that you have (130)
Also,if there is adequate Insulation (R value) on the floor of the attic(ceiling below) then this build up of heat within the attic should not have ANY effect of the areas below the attic.
Again, proper ventilation of an attic consists of soffit/ridge ventilation. The formula for venting an attic is to have a MINIMUM of 1 sq ft of ventilation for every 300 sq ft of attic floor area. 1 sq ft equals 144 sq inches and that is "free " area. Screens on the vents can cause a restriction of up to approx 50%
This screen restriction should be taken into account when calculating the proper amount of ventilation.
Actually, imo, fans are not required in attics as long as there is proper ventilation and insulation. Save the cost of the fan ,wiring, electrical power, etc, and ventilate/insulate it properly in the first place.