No difference other than the motors. The motor on a three phase fan draws a lot less amps thus requiring less power expenses with the same size of motor. If one has access to three phase power, it is highly recommended to go with three phase if available.
This is where marketing comes into play. The turbo fan may outperform traditional styles fans at some static pressures, however, the premium prices do not equal the value, It is always better to purchase a fan with more horsepower rather than turbo.
The square mount fans are usually more money. Depending on static pressure is how they perform. They were designed for the rocket style of aeration, although it is usually more cost effective to go with a bigger round mount fan with a transition which will effectively blow a lot more air.
Inline Centrifugal. This features the best of both worlds. It works well in all types of static pressure and come in standard mount sizes and offers a better deal for your hard earned dollar.
Generally speaking you can size up your fan to 1 hp to 1,000 bushels, however we have found that our customers whom use our exclusive aeration system on flat bottom bins have gone to a 7 hp fan for up to 12,000 bushels and a 10 hp fan for our 19,000 bushel bin package.
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