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Twin Wall to Twin Wall Increaser Ø 125 - Ø 150 (2-125-004)

The Twin Wall to Twin Wall Increaser Ø 125 - Ø 150 from National Flues is an ideal chimney flue accessory designed for both residential and trade applications. This stainless steel increaser seamlessly adapts your twin wall system, ensuring safety and durability for wood, oil, or gas appliances. Read more...
Twin Wall to Twin Wall Increaser Ø 125 - Ø 150
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At a Glance

  • Increases flue diameter from Ø125 to Ø150 for a secure, efficient fit
  • Constructed with durable 304 and 316 stainless steel for long-lasting performance
  • Incorporates compressed rockwool insulation (200kg/m³) for optimal thermal efficiency
  • Quick and reliable installation using a security Locking Band
  • Fully HETAS approved and CE marked to meet stringent safety standards
  • Versatile compatibility with solid fuel, gas, and 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.

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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.

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Have Questions?
Phone: 01670 206999
Email: sales@nationalflues.com

The Twin Wall to Twin Wall Increaser Ø 125 - Ø 150 is a critical component for any chimney system where an increase in flue size is required. Specifically designed for use with solid fuel, gas, and oil appliances, such as woodstoves, gas coal effect fires, and boilers, this increaser caters to a wide range of heating setups. Constructed with a robust 304 grade stainless steel outer skin and a 316 grade stainless steel inner skin, both featuring a thickness of 0.4mm, this product is engineered for durability and longevity.

The incorporation of compressed rockwool insulation, with a density of 200kg/m3, ensures optimal thermal efficiency and safety. All components are fully welded, enhancing the structural integrity. For installation, the Twin Wall Insulated Chimney parts are secured with a reliable Locking Band, and it is crucial to maintain a 50mm distance from any combustible materials to ensure safety.

The TWPro Twin Wall system is HETAS approved and CE marked, adhering to stringent safety standards and regulations.

SKU: 2-125-004

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
ModelTwin Wall to Twin Wall Increaser Ø 125 - Ø 150
Diameter RangeØ125 to Ø150
Inner Material316L Stainless Steel (0.40mm thick)
Outer Material304 Stainless Steel (0.40mm thick)
InsulationCompressed Rockwool (200kg/m³)
Fuel CompatibilityWood, Oil, Gas, Low sulphur coal
ApprovalsHETAS / CE
Minimum Clearance50mm from combustible materials
DesignationEN1856-1 T600 N1 W V2 L50040 G50; EN1856-1 T200 P1 W V2 L50040 020
SystemTWPro Twin Wall
- Installation must be carried out as part of a Twin Wall Insulated Chimney system - Secure the increaser using the provided Locking Band to ensure stability - Maintain a minimum clearance of 50mm from any combustible materials at all times - Follow all manufacturer guidelines and local installation codes - It is recommended to consult a professional installer if unsure about compatibility with existing systems

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

This increaser is suitable for solid fuel, gas, and oil appliances, including woodstoves, gas coal effect fires, and boilers.

Yes, the Twin Wall to Twin Wall Increaser is designed to be easily secured using a Locking Band. However, maintaining a 50mm distance from any combustible materials is essential for safety.

The TWPro Twin Wall Increaser is HETAS approved and CE marked, meeting high safety and quality standards. It complies with designation numbers EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20.

The compressed rockwool insulation, with a density of 200kg/m3, ensures optimal thermal efficiency and reduces heat loss, contributing to the overall safety and performance of the flue system.

This product is designed to increase the twin wall flue size from Ø 125 to Ø 150. Ensure that your current and required flue sizes match these dimensions. For further assistance, consult with a professional or contact our support team.

While designed for TWPro systems, it may be compatible with other twin wall systems. However, we recommend consulting with a professional to confirm compatibility before installation.

 

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