Metal-Fab's round and oval Type-B vent is listed by Underwriters Laboratories for use with approved category 1 gas furnaces, heaters, and boilers. A category 1 appliance operates with a non-positive vent static pressure. The double wall design of B-vent enables the product to be used in homes and commercial buildings at close clearance to combustible. Metal-Fab's B-vent design incorporates features that make installation quick, easy, and safe. Some of those features are:
- Elimination of sharp edges by hemming the flue and casing.
- Assembly & disassembly, without tools, using positive twist lock.
- 360 degree rotation of small diameter fittings using swivel tees, wyes, and elbows.
- Space savings inside standard stud walls using oval pipe.