All standard fan-and-motor combinations on Colmac Coil’s A+ Series air coolers are optimized for maximum total efficiency, according to the company. The change to high-efficiency fan motors serves as an alternative to integral external-rotor fan motor units, which do not always offer the same efficiencies.

The high-efficiency internal-rotor fan motors supplied with the air coolers are totally enclosed and variable-frequency drive (VFD) compatible. Integral horsepower motors (greater than 1 hp) are supplied standard as NEMA premium efficiency.