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FasNSeal® Flex

FasNSeal Flex

Made from super-ferritic stainless steel. Corrosion resistant. Manufactured with a sure-seal locking seam for superior strength and flexibility. The smooth inner-wall provides for no output reduction, allowing for full appliance efficiency, ease of cleaning and regular maintenance. The smooth inner wall optimizes gas flow, minimizes back pressure, and facilitates condensate management. Only flexible chimney liner listed to UL 1738 standard.

  • Specifications
  • Typical Installation
  • Literature

FasNSeal Flex is for use with natural gas or propane Categories II, III and IV appliances or Canada’s Type BH Gas Vent Systems, having a maximum rated operating temperature of 480°F and a maximum positive pressure of 15” water column. FasNSeal can be used on a wide range of applications, including: high efficiency gas boilers, furnaces, booster heaters, pool heaters, water heaters, unit heaters, or tankless water heaters.

Materials and Construction
Single strip double layer super-ferriticstainless steel (totalling .010").

FasNSeal Flex 3"-12"

UL Listed to UL 1738 and UL 1777 and ULC S636.

Refer to our Typical Venting Installation drawings to select the appropriate component parts for your installation.

FasNSeal Typical Installations

More Typical Installations:

FasNSeal Typical Installations

Installation Key
1 Rain Cap
2 Storm Collar
3 Variable Pitch Roof Flashing
4 Vent Length
5 Adjustable Vent Length
6 Firestop/Flat Flashing
7 Horizontal Drip Tee
8 Elbow
9 Universal Condensate Drain
10 Appliance Adapter
11 Top Plate*
12 Male Flex Adaptere
13 FasNSeal Flex
14 Female Flex Adapter
15 Standard Tee

Commercial Applications

Commercial projects may require custom parts and unique system designs. DuraVent offers complete project assistance:

  • Engineering Services: Personalized system design services offer comprehensive CAD submittal drawing and complete bills of materials.
  • Custom Parts: If your project requires innovative solutions, contact DuraVent for custom parts that meet your specific project needs.
  • FasNSeal W2: FasNSeal W2 is the ideal choice for commercial applications where there is a need for low clearances to combustibles.
  • Up to 16” Vent Diameters: Many commercial applications require large diameter systems due to the units size and output. Large diameters are available in single and double wall, featuring FasNSeal’s triple lipped directional gaskets and built-in locking band which provides a safe and convenient installation.