Windmilling (draft induced reverse rotation) of propeller fans is more than an inconvenience. During idle periods or shutdown, natural wind drafts may cause cooler fans to rotate at high speed in reverse. As the cooler powers up, sudden reversal of this rotation results in severe impact loads to the entire drive train and power transmission components. Belts, motors and fans can be damaged and frequently have to be replaced.

The Spin Dr. provides an economical end to those problems. Easy installation by direct bolting to the fan (driven) sheave bushing (QD Style) yields a permanent and immediate end to expenses associated with parts damage/ replacement and cooler down time.