FasNSeal® 80/90 is a unique, patent pending system that exhausts 90+ condensing appliances with Type B atmospheric units within the same vent.

Using your pre-existing common vent, our cap improves the operation of both the remaining atmospheric appliances, and the new condensing unit, while not disturbing finished space during installation.

Finally a solution when you need to deal with narrow lot lines, clearance to window and door openings or when side wall venting just isn’t practical.

The FNS 80/90 system is a tested and listed exhaust vent for the replacement of one Category I gas fired appliance with a high efficiency appliance in an existing Type B common vent system.

DuraVent’s FNS 80/90 Combination Cat I and Cat IV gas vent system is designed and UL listed for use with approved Duravent / Security Chimneys special gas vent components only! Listed to applicable portions of ULC S636/UL1738, UL1777, and UL441.