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Twin Wall to Twin Wall Increaser Ø 80 - Ø 100 (2-80-004)

National Flues presents the Twin Wall to Twin Wall Increaser Ø 80 - Ø 100, a robust and reliable solution designed to optimise your chimney system's performance. Ideal for a variety of heating appliances including wood stoves, oil and gas boilers, this product complies with EN1856-1 standards and is both HETAS approved and CE marked. Read more...
Twin Wall to Twin Wall Increaser Ø 80 - Ø 100
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Now only £58.99
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At a Glance

  • Premium dual stainless steel construction (304 outer, 316 inner)
  • Bridges diameters from Ø80 to Ø100 in 25mm increments
  • Suitable for wood stoves, gas, oil, and low sulphur coal appliances
  • Compressed rockwool insulation (200kg/m³) for enhanced thermal efficiency
  • HETAS approved and CE marked for reliable safety
  • Easy installation with a secure Locking Band

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

We Won't Be Beaten On Price

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: sales@nationalflues.com

The Twin Wall to Twin Wall Increaser Ø 80 - Ø 100 is your ultimate solution for enhancing chimney performance for both solid fuel and gas/oil appliances. This high-quality increaser is perfect for wood stoves, gas coal effect fires, oil and gas boilers, and any other solid fuel appliances. Crafted with precision, the outer skin is made from 304 grade stainless steel at 0.4mm thickness, while the inner skin boasts 316 grade stainless steel, also at 0.4mm thickness.

To ensure outstanding insulation, we've used compressed rockwool with a density of 200kg/m3. All components are fully welded to guarantee durability and safety, maintaining a mandatory 50mm distance from combustibles. Approved by HETAS and CE marked, this increaser meets the highest safety standards (EN1856-1 T600 N1 W V2 L50040 G50; EN1856-1 T200 W V2 L50040 O20).

Installation is a breeze, secured effortlessly with a Locking Band. Enhance your flue system today with a product that doesn’t compromise on quality or safety.

SKU: 2-80-004

Delivery Information* +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Monday, November 17th. This is based on current lead times. Bear in mind that it is a busy time of year. If you need a product delivered by a specific time in the next 7 days, then please give us a call on 01670 206 999. Visit our Shipping Information page for more information.

About National Flues Ltd +

We began over 30 years ago as a fireplace shop in the North East. We now supply hundreds of trade professionals and thousands of retail customers, all across the UK, every month. We are still a family owned business, lead by the MD Neil, and always try our best to deliver the best possible experience. We also price match, so give us a call if you find this cheaper and want to buy from us. Visit our about us page to read a bit more.

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Technical Specifications
SKU2-80-004
DimensionsDiameters Ø80 to Ø100, increasing in 25mm increments
Outer Material304 Stainless Steel, 0.4mm thick
Inner Material316 Stainless Steel, 0.4mm thick
InsulationCompressed Rockwool, 200kg/m³
Fuel CompatibilityWood, Oil, Gas, Low Sulphur Coal
ApprovalsHETAS, CE marked (EN1856-1 T600 N1 W V2 L50040 G50; EN1856-1 T200 W V2 L50040 O20)
Installation DistanceMinimum 50mm from combustibles
Fixing MethodSecured with a Locking Band
Before installing the Twin Wall to Twin Wall Increaser, ensure that all preparatory work is completed by a certified professional. Always maintain a minimum clearance of 50mm from any combustible material. Begin by aligning the increaser with the existing flue system; then secure each section using the provided Locking Band, ensuring a firm, leak-proof connection. Double-check all welded joints for integrity and compliance with manufacturer guidelines. If in doubt at any step, consult the detailed installation manual or contact a qualified installer to avoid compromising safety.

It is suitable for wood stoves, gas coal effect fires, oil and gas boilers, and any solid fuel appliances.

The outer skin is made of 304 grade stainless steel and the inner skin from 316 grade stainless steel, both at 0.4mm thickness.

Compressed rockwool with a density of 200kg/m3 is used for insulation.

It is secured using a Locking Band, ensuring a tight and safe connection.

Yes, it is HETAS approved and also CE marked, meeting EN1856-1 T600 N1 W V2 L50040 G50; EN1856-1 T200 W V2 L50040 O20 standards.

You should always maintain a 50mm distance from any combustible material such as wood or plasterboard.

The increaser bridges gaps between Ø 80 to Ø 100, increasing in 25mm increments.

 

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