Profile: Canada Blower Ltd. is a supplier of industrial and commercial centrifugal and axial fans, blowers, ventilators for various air moving applications. Our products include centrifugal roof exhausters, axial roof ventilators, circulating fans, and air handling units. A direct gas-fired air handling unit has a gas burner installed directly in the outside makeup-air stream. The products of combustion (carbon dioxide (CO2), carbon monoxide (CO), nitrogen dioxide (NO2)) are discharged directly into the makeup air stream and supplied to the building area.