The problem with making a definitive statement on attic fans is that every house is different.
Attic fans worth it.
Of course if the attic fan isn t working correctly and is running all year long that would be a significant problem.
If the attic fan increases the comfort level of the house it may be worth it.
Are attic fans worth it.
There are different climates all around the country some climates are more beneficial to attic fans.
Good insulation reduces fan effectiveness.
If the attic fan keeps the house cool enough so that the owners leave the ac off there is almost certainly an energy benefit.
If you have good continuous soffit venting and a ridge vent then any type of attic fan may be totally unnecessary.
However the utility of attic ventilation fans is actually quite a controversial topic.