Our Veritcal line of boilers, are space saving work horses that meet requirments for UL, SCAQMD, FM, and IRI codes. The Cyclone Boiler is a four-pass vertical design passing the flame around the water chamber four times via ports and fins. Giving you more BTU's into the water than out your exhaust stack. With the small design you will save space in rooms were there is little space to enlarge.