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Sflue Black (2119706B) - Increaser - Ø 127-152mm (42-125-002)

National Flues presents the Sflue Black Increaser - Ø 127-152mm, a premium upgrade designed for modern flue systems in the UK. Perfectly suited for wood stoves, gas coal effect fires and oil/gas boilers, this cutting-edge increaser from National Flues delivers both high performance and robust safety features. With its HETAS approval and CE marking, you are assured a product that not only meets but exceeds industry standards. Whether you refer to it as a chimney flue adapter or a flue diameter in Read more...
The price you pay today £118.99
including free delivery Give us a call if you find it cheaper and we'll normally price match.

 

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At a Glance

    Increases flue diameter from Ø127mm to Ø152mm
    Constructed with robust 316L (inner) and 304 (outer) stainless steel – 0.40mm thick
    Compressed rockwool insulation for enhanced thermal efficiency
    HETAS approved and CE marked for trusted safety standards
    Easy installation with 8-barbed twist-lock system and locking band
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Tuesday, July 1st. This is based on current delivery times for this product. Delivery for products not in our warehouses can be delayed because of third party carriers. If you need a stove, or other bulky product, to be delivered by a specific time in the next 7 days then please give us a call. We can sometimes reduce longer lead times if we pay the carrier £25 for express delivery. Visit our Shipping Information page for more information.

Warranty & Returns +

All our products come with warranties and you can read in our blog about they types and terms and conditions for warranties. Mi-Flex flue liner, for example, comes with a lifetime guarantee. Give us a call if you want to know about a specific warranty. Returns for damaged items are covered by insurance; non-damaged returns incur return delivery costs.

Price Match Guarantee +

We will match any price, like-for-like, on a retail basis. Give us a call if you find it cheaper and want to buy from us.

Please Note: All dimensions refer to the internal diameter of flues. If unsure, please call 01670 206999 to ensure you choose the correct products.

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At National Flues, we continuously monitor competitor prices. This ensures that we consistently offer you the best deals on all our products. Here’s how we keep your costs low:

  • Daily Price Matching: Our team adjusts prices to ensure we stay competitive.
  • Bulk Purchasing Power: We sell a lot, so we can negotiate better rates with suppliers, passing the savings directly to you.
  • Operational Efficiency: We have streamlined processes to reduce overhead.

Price Match Guarantee: If you find the same product cheaper within 48 hours, we’ll match it and refund the difference.

Free Delivery Over £100: Orders over £100 are free delivery (call us if delivery is required outside the mainland UK).

“I saved 20% on my purchase compared to other retailers. Exceptional service!” – Jane D.

Have Questions?
Phone: 01670 206999
Email: [email protected]

The Sflue Black (2119706B) Increaser - Ø 127-152mm is designed for seamless integration into your flue system, equipped to handle a variety of heating appliances including wood stoves, gas coal effect fires, and oil and gas boilers. Constructed with robust materials, the outer skin is made from 304 grade stainless steel while the inner lining consists of 316 grade stainless steel. Both skins are 0.4mm thick.

The increaser includes compressed rockwool insulation with a density of 230kg/m3, encapsulated within twist-lock couplers for enhanced efficiency. Fully laser welded, it ensures utmost durability and performance. This product maintains a safe distance of 50mm between the flue and any combustible materials.

HETAS approved and CE marked, it meets high industry standards (EN1856-1 T450 N1 D V2 L50040 G50). Installation is straightforward with its 8-barbed twist lock system and locking band, ensuring secure and reliable connections.

SKU: 42-125-002

Technical Specifications
SKU42-125-002
Product NameSflue Black Increaser - u00d8 127-152mm
Dimensionsu00d8127mm to u00d8152mm
Inner Material316L Stainless Steel (0.40mm thick)
Outer Material304 Stainless Steel (0.40mm thick)
InsulationCompressed Rockwool, 230kg/m3
ApprovalHETAS / CE
Minimum Clearance50mm from combustibles
Warranty15 Years manufacturing defect, 2 Years paint warranty
• Ensure that the flue is clear of any obstructions and that the area maintains a minimum clearance of 50mm from any combustible material. • Follow the manufacturer’s installation guide by aligning the 8-barbed twist-lock system carefully to provide a secure, tight fit. • Use the provided locking band to firmly secure the increaser in place. • Check all joints and connections for stability before energising your heating appliance. • If unsure, consult a professional installer to guarantee compliance with local safety regulations.

The Sflue Black Increaser is suitable for use with solid fuel, gas, and oil appliances, including woodstoves, gas coal effect fires, and oil and gas boilers.

Ensure there is a distance of 50mm between the outside of the flue and any combustible materials such as wood or plasterboard.

The outer skin is made from 304 grade stainless steel, and the inner skin is constructed from 316 grade stainless steel, both with a thickness of 0.4mm. Insulation is provided by compressed rockwool with a density of 230kg/m3, encapsulated within twist-lock couplers.

Yes, the Sflue Black Increaser is HETAS approved and also CE marked, ensuring it meets high safety and performance standards.

The Sflue Black Increaser uses an 8-barbed twist lock twin wall insulated chimney system, which is secured together using a locking band for a secure fit.

The insulation is made from compressed rockwool with a density of 230kg/m3, encapsulated within twist-lock couplers for maximum efficiency.

You can purchase the Sflue Black Increaser from National Flues. We offer secure online payments and reliable nationwide delivery.

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