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Single Wall to Twin Wall Increaser Ø 125 - Ø 150 (2-125-002)

National Flues proudly presents the Single Wall to Twin Wall Increaser Ø 125 - Ø 150, engineered to provide a reliable and efficient transition between single wall flue pipes and twin wall systems. Crafted from premium stainless steel and enhanced with compressed rockwool insulation, this TWPro adaptor is ideal for a range of applications including wood, gas, and oil appliances. Read more...
Single Wall to Twin Wall Increaser Ø 125 - Ø 150
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At a Glance

  • Designed for seamless connection between single wall and twin wall systems
  • Constructed with durable 304-grade (outer) and 316-grade (inner) stainless steel, both 0.4mm thick
  • Features compressed rockwool insulation (200kg/m3) for optimal thermal efficiency
  • Tapered design increases diameter by 25mm ensuring a smooth transition
  • Fully HETAS approved and CE marked for safe, compliant installations
  • Suitable for a variety of appliances including wood stoves, gas coal effect fires, oil and gas boilers

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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Phone: 01670 206999
Email: sales@nationalflues.com

The Single Wall to Twin Wall Increaser Ø 125 - Ø 150 is the perfect solution for connecting various appliances to your TWPro Twin Wall Insulated Chimney system. Suitable for use with solid fuel and gas/oil appliances, such as woodstoves, gas coal effect fires, and oil and gas boilers, this increaser ensures a smooth and efficient transition. Constructed with 304-grade stainless steel for the outer skin and 316-grade stainless steel for the inner skin, both 0.4mm thick, this increaser guarantees durability and corrosion resistance.

The insulation is composed of compressed rockwool, achieving a density of 200kg/m3, providing exceptional thermal insulation. Fully welded parts ensure airtight connections, with a necessary clearance of 50mm from combustibles to enhance safety. This product meets rigorous industry standards with HETAS approval and CE marking, adhering to EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20 certifications.

Designed for easy installation, TWPro parts are secured with a locking band, ensuring reliable performance for all your chimney system needs.

SKU: 2-125-002

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
ModelSingle Wall to Twin Wall Increaser Ø 125 - Ø 150
ConstructionOuter: 304-grade Stainless Steel (0.4mm thick), Inner: 316-grade Stainless Steel (0.4mm thick)
InsulationCompressed Rockwool (200kg/m3 density)
CertificationsHETAS / CE (EN1856-1 T600 N1 W V2 L50040 G50, EN1856-1 T200 W V2 L50040 O20)
Clearance50mm from combustibles
CompatibilitySuitable for wood stoves, gas coal effect fires, oil/gas boilers
DesignTapered increment increases diameter by 25mm for optimal transition
Before commencing installation, ensure you have read the manufacturer’s guidelines thoroughly. Begin by securely fitting the locking band to join the increaser with your TWPro Twin Wall Insulated Chimney system. Maintain a clearance of 50mm from any combustible materials, such as wood or plasterboard. Use appropriate tools and follow safety procedures to guarantee an airtight connection. If installing in a challenging position, double-check that all measurements conform to the safety standards outlined in the installation manual. It is advisable to wear protective gear throughout the installation process and, if in doubt, consult a professional installer to ensure compliance with local building regulations.

The Single Wall to Twin Wall Increaser Ø 125 - Ø 150 is suitable for solid fuel and gas/oil appliances, including woodstoves, gas coal effect fires, and oil and gas boilers.

The increaser is constructed with an outer skin of 304-grade stainless steel and an inner skin of 316-grade stainless steel, both 0.4mm thick. The insulation is compressed rockwool with a density of 200kg/m3.

Yes, the product is HETAS approved and CE marked, adhering to EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20 certifications.

Installation involves securing the TWPro Twin Wall Insulated Chimney parts with a locking band and ensuring a 50mm clearance from any combustible materials such as wood or plasterboard.

The increaser connects single wall flue pipes or vitreous enamel pipes to twin wall systems, ensuring a smooth transition for efficient flue system performance.

A clearance of 50mm must be maintained from the outside of the flue to any combustible material such as wood or plasterboard.

The tapered design allows for a smoother transition between single wall and twin wall systems, increasing the diameter by 25mm and enhancing operational efficiency.

 

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