DuraVent DuraFlex Aluminum Length
Use with Category I gas-burning appliances with draft hood. UL 1777 aluminum liner. Flex lengths available in 25’, 35’, and 50’.
Overview DuraFlex Aluminum
An economical venting system used for relining masonry chimney for natural gas or liquid propane category I, draft hood equipped appliances, and appliances tested and listed to use Type B Gas Vent for a wide range of applications, including: natural gas fireplaces, gas-fired furnaces, boilers, water heaters, and wall or space heating applications. Protects the masonry chimney from damaging effects of flue product condensation.
Details
SKU: 3DFA-25 | 4DFA-25 | 5DFA-25 | 55DFA-25 | 6DFA-25 | 7DFA-25 | 8DFA-25
Applications
DuraFlex AL (DFAL) aluminum flexible relining for masonry chimney. Use with natural gas or liquid propane category I, draft hood equipped appliances, and appliances tested and listed to use Type B Gas Vent. Applications include: natural gas fireplaces, gas-fired furnaces, boilers, water heaters, and wall or space heating applications
Materials and Construction
Single-wall .010″ aluminum (2-ply of .005″).
Clearances
0″ clearance to masonry.
Diameters
3″, 4″, 5″, 5″, 6″, 7″, and 8″
Listings
Listed to UL 1777 and ULC S635.
Instructions
Typical Installation
Refer to our Typical Venting Installation drawings to select the appropriate component parts for your installation
More Typical Installations:
Installation Key
| 1 | DuraCap |
| 2 | Storm Collar |
| 3 | Roof Flashing |
| 4 | High-Wind Cap |
| 5 | Round Pipe |
| 6 | Elbow |
| 7 | Tee |
| 8 | Tee Cap |
| 9 | Increaser Tee |
| 10 | Female Flex Adapter |
| 11 | Male Adapter |
| 12 | Double-Wall Wye |
| 13 | Pipe Collar |
| 14 | Increaser |
| 15 | Draft Hood Connector |
| 16 | Square Firestop Support |
| 17 | Oval Pipe |
| 18 | Oval to Round Adapter |
| 19 | Oval Tee |
| 20 | Oval Tee Cap |
| 21 | Oval Tee Support |
| 22 | Oval Firestop Spacer |
| 23 | DuraConnect II |
| 24 | DuraFlex AL Length |
| 25 | DuraFlex Motar Sleeve |
| 26 | DuraFlex AL Coupling |
How Size and Height Affect Stove Performance
- The amount of heat the vent gases loose as they flow determines how much condensation will occur and how strong the draft will be. To control the heat loses, proper selection of venting materials is of vital importance.
- Double-wall Type B Gas Vent, with an aluminum inner wall and a galvanized steel outer wall, has proven to be the ideal choice in venting materials.
Vent Termination Chart
Using listed Type B Gas Vent caps may terminate in accordance with this table.
| Minimum height | ||
|---|---|---|
| Roof Pitch | Feet | Meters |
| Flat to 7/12 | 1 | 0.30 |
| Over 7/12 to 8/12 | 1.5 | 0.46 |
| Over 8/12 to 9/12 | 2 | 0.61 |
| Over 9/12 to 10/12 | 2.5 | 0.76 |
| Over 10/12 to 11/12 | 3.25 | 0.99 |
| Over 11/12 to 12/12 | 4 | 1.22 |
| Over 12/12 to 14/12 | 5 | 1.52 |
| Over 14/12 to 16/12 | 6 | 1.83 |
| Over 16/12 to 18/12 | 7 | 2.13 |
| Over 18/12 to 20/12 | 7.5 | 2.29 |
| Over 20/12 to 21/12 | 8 | 2.44 |
Gas Vent Specification Chart
| Item | Clearances | Maximum Height | Outer Tube Ø | Materials | Locking Device | UL Listing | ULC Listing |
|---|---|---|---|---|---|---|---|
| Type B Vent Round 3″-8″ | 1 inch to combustibles | 100 feet | 5/8″ larger than ID | Inner – .012″ Aluminum Outer – .018″ Galvanized | DuraLock | MH6357 | CMH1276 |
| Round 10″ to 16″ See note 2 | 1 inch to combustibles | 100 feet | 1″ larger than ID | Inner – .016″ Aluminum Outer – .021″ Galvanized | TwistLock Screws | MH6357 | CMH1276 |
| Round 18″ to 30″ | 1 inch to combustibles | 100 feet | 2″ larger than ID See note 5 | Inner – .020″ Aluminum Outer – .021″ Galvanized | Screws | MH6357 | CMH1276 |
| Oval Type B Vent 4″ and 5″ | 2″ x 4″ & 2″ x 6″ stud wall and 1 inch to combustibles | See Note 3 | 2 1/2″ x 7 1/4″ 3 1/8″ x 10 7/8″ | Inner – .012″ Aluminum Outer – .018″ Galvanized | Button Lock | MH6357 | CMH1276 |
| Oval Type B Vent 6″ | 2″ x 6″ stud wall and 1 inch to combustibles | See Note 3 | 3 1/4″ x 12″ | Inner – .012″ Aluminum Outer – .018″ Galvanized | Button Lock | MH6357 | CMH1276 |
| Type B Vent 3″ to 6″ Round Liner” | 0″/Masonry | 50 feet | 5/8″ larger than ID | Inner – .012″ Aluminum Outer – .018″ Galvanized | DuraLock | MH14420 MH6357 | CMH1407 |
| DuraFlex AL Gas Relining 3″ to 6″ | 0″/Masonry | 50 feet | 1/4″ larger than ID | .010″ Aluminum Flex | Screws DuraLock | MH14420 | — |
| DuraConnect 3″ to 6″ | 1 inch to combustibles | See Note 4 | 1/4″ larger than ID | .010″ Aluminum Flex .018″ Galvalume | DuraLock | MH14089 | — |
| DuraConnect II 3″ to 6″ | 1 inch to combustibles | See Note 4 | 1/4″ larger than ID | .010″ Aluminum Flex .018″ Galvalume | DuraLock | MH14089 | — |
Note:
- Clearance to combustibles is the air space between vent and combustibles.
- Maximum height varies with equipment over 50′, for taller applications refer to SDV sizing handbook (L202). 14″-16″ Pipe require screws.
- When oval is used on wall furnaces, minimum height required from bottom of furnace to cap is 12′, minimum 16″ stud space.
- Limited by sizing tables.
- 18″ pipe OD is one inch larger than ID and 20″ – 30″ OD is 2″ greater than ID
Shipping / Freight / Return Info
Same-Day / 24 hour shipping
Same-Day/24 hour shipping - If we have the product in stock, we can ship
same day if ordered before 12pm Monday - Friday (CST).
Freight Claims Policy
Please follow these very important steps when it comes to Freight Items that are damaged or missing
- Open and inspect the order while the delivery driver is present. If delivery driver does not provide sufficient time to do so, please notate the delivery receipt.
- By signing the delivery receipt without noting any damage or missing items, you confirm that your order arrived complete and in excellent condition.
- Record any damage or missing pieces directly on the delivery receipt.
- Do not discard damaged item(s) or any original packaging. For severe damage, write “Refused due to damage” on the delivery receipt and contact us immediately.
- Report any damage within two business days, including delivery details and photos showing the issue
- Damaged item(s) must be returned within 30 days. Failure to return them will result in a charge to the original payment method.
Return Merchandise Authorization Policy
Please follow these very important steps when Returning Items. Contact our team.
- Submit your return request within 30 days of delivery.
- You will receive an email within 1-2 business days confirming whether your return request has been approved or denied.
- Please also note that a 20% restocking fee may apply to approved returns
- If approved, you will receive an itemized Return Authorization, return shipping labels (if requested), and detailed instructions within 1–2 business days
- From the date this email is received, you will have 14 days to return the product.
- Once our distributor receives and inspects the returned item(s), your refund will be issued within 1–2 weeks
- Items returned outside of this process or time frame are not eligible for a refund.
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