DuraVent DuraFlex Pro Tee Kit: for a side connection and bends inside the chimney
The DuraVent DuraFlex Pro Tee Kit is a flexible stainless steel liner kit for an appliance connected through the chimney’s side wall. Its Pro liner bends around turns inside the chimney. DuraFlex Stainless is DuraVent’s flexible stainless steel liner for relining a masonry chimney that vents a wood, pellet, oil, or gas appliance. The box includes a Pro liner coil, a chimney top plate with a welded collar that sheds rain, a removable chimney cap, and a tee with cap. The tee connects at the bottom, where its cap opens for cleaning.
DuraFlex Stainless fittings have built in clamps that tighten around the liner’s ridges without drilling or riveting the liner. Damaged or oversized clay flues can cause fire and draft problems. A stainless liner keeps exhaust away from damaged masonry. Choose a length of 15, 20, 25, 30, or 35 feet, then a diameter from 3 to 8 inches, including 5 1/2 inch. Insulation is separate. Need a connector instead of a tee? See the DuraVent DuraFlex Pro Basic Kit with connector. The DuraVent DuraFlex Pro Tee Kit ships free from My Cozy Outdoors with No Sales Tax (except WY) and the full manufacturer warranty.
Details
SKU: 3DFPRO-15KT | 4DFPRO-15KT | 5DFPRO-15KT | 55DFPRO-15KT | 6DFPRO-15KT | 7DFPRO-15KT | 8DFPRO-15KT
SKU: 3DFPRO-20KT | 4DFPRO-20KT | 5DFPRO-20KT | 55DFPRO-20KT | 6DFPRO-20KT | 7DFPRO-20KT | 8DFPRO-20KT
SKU: 3DFPRO-25KT | 4DFPRO-25KT | 5DFPRO-25KT | 55DFPRO-25KT | 6DFPRO-25KT | 7DFPRO-25KT | 8DFPRO-25KT
SKU: 3DFPRO-30KT | 4DFPRO-30KT | 5DFPRO-30KT | 55DFPRO-30KT | 6DFPRO-30KT | 7DFPRO-30KT | 8DFPRO-30KT
SKU: 3DFPRO-35KT | 4DFPRO-35KT | 5DFPRO-35KT | 55DFPRO-35KT | 6DFPRO-35KT | 7DFPRO-35KT | 8DFPRO-35KT
Applications
- DuraFlex Pro ultra flexible relining for masonry chimney. Use with gas, wood pellet, oil, or wood appliances. Applications include: fireplace inserts, furnaces, boilers, and water heaters.
- DuraFlex SW smooth wall flexible relining for masonry chimney. Use with gas, wood pellet, oil, or wood appliances. Applications include: fireplace inserts, furnaces, boilers, and water heaters.
- DuraFlex 316 flexible relining for masonry chimney. Use with gas, wood pellet, oil, or wood appliance. Applications include: fireplace inserts, furnaces, boilers, and water heaters. 316 is designed for use in harsher conditions, for more resistance to corrosion, such as coal.
- DuraFlex 304 flexible relining for masonry chimney. Use with gas, wood pellet, oil, or wood appliances. Applications include: fireplace inserts, furnaces, boilers, and water heaters.
Materials and Construction
DuraFlex Pro: Single-wall .005″ 316 stainless steel.
DuraFlex SW: Single-wall .005″ overlapped 316 stainless steel (totalling .010″). Overlapped to create smooth inner wall.
DuraFlex 316 & 304: Single-wall .005” 316 or 304 stainless steel.
Clearances
DuraFlex Pro: 0″ clearance for gas, oil, and pellet applications. 1″ clearance to masonry for wood-burning applications. Insulation is required for 0″ clearance to masonry for wood-burning.
DuraFlex SW: Clearances 0″ clearance for gas, oil, and pellet applications. ” clearance to masonry for wood-burning applications. Insulation is required for 0” clearance to masonry for wood-burning.
DuraFlex 316 & 304: 0″ clearance for gas, oil, and pellet applications. 1″ clearance to masonry for wood-burning applications. Insulation is required for 0″ clearance to masonry for wood-burning.
Diameters
DuraFlex Pro & SW: 3″ – 12″.
DuraFlex 316 & 304: 3″ – 8″.
Listings
DuraFlex Pro: Listed to UL 1777 and ULC S635 (MH45609).
DuraFlex SW: Listed to UL 1777 (MH45609).
DuraFlex 316 & 304: Listed to UL 1777 and ULC S635 (MH45609).
FAQ
What is in the DuraFlex Pro Tee Kit, and when do I need a tee?
A Top Plate with welded Storm Collar, a Removable Vertical Cap, a stainless Tee with Cap and one DuraFlex Pro flex length. Choose the tee kit when the appliance enters the chimney from the side, typically a freestanding stove or furnace connected through a thimble in the chimney wall; the tee turns the liner toward the appliance and its cap gives a clean-out at the bottom.
How do I size the flex length and diameter?
Pick the flex length first (15, 20, 25, 30 or 35 feet) and then the diameter, 3 to 8 inches, on the selectors above. The liner must match the appliance outlet and reach from the tee to a few inches above the chimney top; DuraFlex Pro can be cut to length with a hacksaw or reciprocating saw and ovalized if the flue is tight.
Does the liner need insulation or clearance?
For gas, oil and pellet appliances DuraFlex Pro is listed at zero clearance to the masonry with no insulation required, though DuraVent notes insulation improves draft, especially on exterior chimneys. For wood burning the liner needs 1 inch to the masonry or a 1/2-inch ProFoil or Flexwrap blanket (1 inch of TherMix) to be listed at zero clearance; the ProMesh insulation kit is sold separately.
Why choose DuraFlex Pro over the 304 or 316 kits?
Pro is DuraVent’s most flexible liner, with 20 percent more 316 stainless per foot, built for chimneys with several offsets; the 304 and 316 liners are lighter, more economical options for flues with minimal offsets. All three are listed to UL 1777 and ULC S635. If the appliance connects straight down from the top, the Basic or Top Plate/Cap kit replaces this tee kit.
What does the warranty require?
DuraFlex Pro carries DuraVent’s limited lifetime warranty to the original purchaser, conditional on installation per the instructions, a chimney cap, annual inspection and cleaning by a qualified sweep and no chemical chimney cleaners; chimney-fire damage is excluded. Have the masonry inspected before relining. Connectors and tees are in the DuraFlex Stainless category.