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Twin Wall to Flex Adaptor Ø 125 (2-125-099)

National Flues presents the Twin Wall to Flex Adaptor Ø 125 – a must-have transitional component designed for seamless integration between traditional TWPro twin wall systems and MI-Flues multi-fuel liners. Read more...
Twin Wall to Flex Adaptor Ø 125
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Now only £52.99
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At a Glance

  • Seamless transition from twin wall systems to flexible liners
  • Constructed from high-grade 304 and 316 stainless steel
  • Compressed rockwool insulation (200kg/m³) for optimal heat retention
  • Fully welded design ensuring durability
  • Maintains a safe 50mm clearance from combustibles
  • HETAS approved and CE marked for safety and compliance
  • Designed for both solid fuel and gas/oil appliances

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.
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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 Flex Adaptor Ø 125 is essential for connecting your chimney and flue system, ensuring a secure transition from TWPro twin wall systems to MI-Flues multi-fuel liners. Specifically designed for use with solid fuel and gas/oil appliances, including wood stoves, gas coal effect fires, and boilers, this adaptor guarantees high efficiency and safety. Constructed with 0.4mm thick outer and inner skins made of 304 and 316 grade stainless steel respectively, it boasts insulation of compressed rockwool with a density of 200kg/m³.

Fully welded for additional durability, every part maintains a safe 50mm distance to combustible materials. TWPro components are HETAS Approved and CE marked, with designations EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20. Installation is straightforward, requiring a locking band to secure the parts.

Ensure all transitions occur inside an existing class 1 chimney, with no flexible liner visible externally, for optimal performance.

SKU: 2-125-099

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
ModelTwin Wall to Flex Adaptor Ø 125
SKU2-125-099
Inner Material316L Stainless Steel, 0.4mm thick
Outer Material304 Stainless Steel, 0.4mm thick
InsulationCompressed Rockwool (200kg/m³)
Appliance CompatibilityWood stoves, gas coal effect fires, oil/gas boilers, and other solid fuel appliances
ApprovalsHETAS Approved / CE Marked
DesignationsEN1856-1 T600 N1 W V2 L50040 G50, EN1856-1 T200 W V2 L50040 O20
Minimum Clearance To Combustibles50mm
Installation RequirementLocking band for secure coupling, inside an existing class 1 chimney
Ensure your installation is carried out within an existing class 1 chimney. The adaptor requires a locking band to secure the connection between the twin wall system and the flexible flue liner. It is critical that a minimum distance of 50mm is maintained from any combustible material, such as wood or plasterboard. During installation, verify that the flexible liner is completely concealed within the chimney structure – it must not be visible externally. Follow all manufacturer guidelines and local building regulations to ensure both performance and safety. Optional accessories, like additional locking bands or custom fittings, are available to further secure and optimise your installation if required.

The Twin Wall to Flex Adaptor Ø 125 is suitable for solid fuel and gas/oil appliances, including wood stoves, gas coal effect fires, oil and gas boilers, and other solid fuel appliances.

This adaptor is made from 304 grade stainless steel for the outer skin and 316 grade stainless steel for the inner skin, both measuring 0.4mm in thickness. It also includes compressed rockwool insulation with a density of 200kg/m³.

Yes, it is HETAS Approved and CE marked, meeting designations EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20.

Installation is simple with the use of a locking band to secure the parts together. Ensure that there is a 50mm distance from the outside of the flue to any combustible materials and that the transition occurs inside an existing class 1 chimney.

The safe distance to combustibles is 50mm. Ensure no part of the flue is within 50mm of any combustible material like wood or plasterboard.

No, the flexible flue liner should not be visible outside the brick or clay chimney. The transition must be made entirely inside an existing class 1 chimney.

National Flues offers competitive prices, reliable delivery, and excellent service to both retail and trade customers. Our products, including the Twin Wall to Flex Adaptor Ø 125, ensure quality and compliance with industry standards.

 

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