On the other hand fans are widely used for cooling purposes, fans generally work under a consistent temperature range and are not subject to any environmental extremes. They are heavy duty equipment and have a sturdy long lasting built quality.
Fans are easy to maintain and repair and can be cleaned easily just because of their simple operational needs whereas a blower might need some serious maintenance efforts as depending upon the application it may or may not be subjected to harsh working conditions and extreme debris and affluents.
A blower used in the industrial application will surely be exposed to high temperature, humidity and ash and similar kind of industrial waste which can impact its service life and durability.
A fan would essentially be powered by electricity in current scenarios whereas a blower also has a human labor-centric option where a handle is used to drive the fan unit of the blower. There is also a clear difference between the cost of these two units. A blower most of the times will be expensive than its counterpart within same scale and usability.