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TWPro MB - Twin Wall to Twin Wall Increaser - Ø 100-125mm (37-100-004)

Enhance your chimney's performance with the TWPro MB Twin Wall to Twin Wall Increaser Ø 100-125mm. This TWPro product, ideal for solid fuel and gas appliances, is a top choice for those seeking durability, efficiency, and safety. Read more...
TWPro MB - Twin Wall to Twin Wall Increaser - Ø 100-125mm
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Now only £64.99
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At a Glance

  • Robust design engineered for seamless transition from 100mm to 125mm flue diameters
  • Constructed with 316L stainless steel inner skin and 304 stainless steel high temperature black coated outer skin
  • Compressed rockwool insulation (200kg/m³) ensures optimal thermal performance
  • HETAS approved and CE marked for safety and regulatory compliance
  • Simplified installation with an included Locking Band
  • Versatile compatibility with wood, gas, and oil appliances
  • Maintains safe 50mm clearance to combustible materials for reliable, secure operation

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.
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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).

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

The TWPro MB - Twin Wall to Twin Wall Increaser Ø 100-125mm is specifically designed for solid fuel and gas/oil appliances, such as wood stoves, gas coal effect fires, oil boilers, and gas boilers. This increaser allows you to smoothly transition between different flue sizes, enhancing the efficiency and performance of your chimney system.Constructed with an outer skin of 304 stainless steel, coated with a high-temperature black finish, and a 316-grade stainless steel inner skin, the increaser promises durability and resistance to high temperatures. The compressed rockwool insulation (density of 200kg/m³) ensures optimal thermal performance while maintaining safety standards.TWPro products are HETAS approved and CE marked, meeting the stringent quality and safety norms.

The product designation numbers are EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 P1 W V2 L50040 O20.Installation is hassle-free with the provided Locking Band, ensuring secure assembly. It's critical to maintain a 50mm distance from combustible materials such as wood and plasterboard to the exterior of the flue for safety.

SKU: 37-100-004

Delivery Information* +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, November 14th. 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
SKU37-100-004
Increaser SizeØ 100-125mm
Inner Material316L Stainless Steel (0.40mm thick)
Outer Material304 Stainless Steel - High Temperature Black Coated (0.40mm thick)
InsulationCompressed Rockwool (200kg/m³)
CertificationsHETAS / CE
Minimum Clearance50mm from combustible materials
Compatible FuelsWood, Oil, Gas, Low Sulphur Coal
Included AccessoryLocking Band for secure installation
Installation is designed to be straightforward. First, verify that all included components are available before beginning. The TWPro MB Increaser comes with a Locking Band that simplifies securing the increaser into place. Carefully align the increaser with your existing twin wall flue system, ensuring that the inner and outer skins are properly oriented. Always maintain a minimum 50mm clearance from any combustible materials such as wood or plasterboard. Although the product is crafted for ease of installation, always consult with a professional chimney technician if you are unsure. Additionally, consider exploring optional accessories such as adjustable sealing kits or extra insulation packs to further tailor the installation to your home's specific needs.

The increaser is suitable for solid fuel and gas/oil appliances like wood stoves, gas coal effect fires, oil boilers, and gas boilers.

The outer skin is made from 304-grade stainless steel with a high-temperature black finish. The inner skin is made from 316-grade stainless steel.

Yes, the TWPro MB increaser is HETAS approved, ensuring it meets high safety and performance standards.

The increaser comes with a Locking Band, which makes the installation process simple and secure.

You should maintain a minimum distance of 50mm from any combustible materials such as wood or plasterboard.

The increaser is insulated with compressed rockwool, offering a density of 200kg/m³ for optimal thermal performance.

Yes, this increaser is versatile and suitable for both gas and solid fuel appliances.

 

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