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TWPro MB - Twin Wall to Twin Wall Increaser - Ø 125-150mm (37-125-004)

National Flues proudly presents the TWPro MB - Twin Wall to Twin Wall Increaser (Ø 125-150mm), a premium chimney adapter designed for both solid fuel and gas/oil appliances. This high-performance conversion device is engineered to upgrade your existing flue system while ensuring safety and efficiency. Read more...
TWPro MB - Twin Wall to Twin Wall Increaser - Ø 125-150mm
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Now only £66.99
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At a Glance

  • Compatible with solid fuel and gas/oil appliances
  • Robust construction with dual stainless steel layers
  • High temperature black coated outer skin
  • Compressed rockwool insulation (200kg/m3) for efficient heat retention
  • HETAS approved and CE marked for safety
  • Maintains a safe 50mm clearance from combustibles

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:

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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 125-150mm) is a versatile component designed for solid fuel and gas/oil appliances including woodstoves, gas coal effect fires, oil boilers, and gas boilers. Constructed with an outer skin of 304 stainless steel and an inner skin of 316 stainless steel, both 0.4mm thick, this increaser guarantees durability and superior performance. The high temperature black finish on the outer skin not only enhances its aesthetic appeal but also provides robust protection against heat.

The insulation is made of compressed rockwool with a density of 200kg/m3, ensuring efficient heat retention. Fully welded for robustness, this increaser mandates a safe distance of 50mm from combustible materials such as wood and plasterboard. Proudly carrying HETAS approval and CE marking, it adheres to EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 P1 W V2 L50040 O20 standards.

Installation is straightforward, requiring the use of a Locking Band to secure the parts together, ensuring a hassle-free setup.

SKU: 37-125-004

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
SKU37-125-004
Size125mm to 150mm
Inner Material316L Stainless Steel - 0.40mm thick
Outer Material304 Stainless Steel - 0.40mm thick with high temperature black coating
InsulationCompressed Rockwool (200kg/m3)
ApprovalsHETAS / CE
Clearance50mm from combustible materials
DesignationEN1856-1 T600 N1 W V2 L50040 G50 / EN1856-1 T200 P1 W V2 L50040 O20
SystemTWPro Black
ApplicationsWoodstoves, gas coal effect fires, oil boilers, gas boilers
The TWPro MB increaser installation is straightforward and secure. Ensure that you follow these key steps: • Maintain a minimum 50mm clearance from any combustible materials such as wood or plasterboard. • Use the provided Locking Band to securely join the parts of the increaser for a robust and safe setup. • Always check that the increaser is correctly aligned with the twin wall flue system to avoid any gaps or misalignments that could compromise safety or performance. • If you are uncertain about the installation process, consult a professional installer to guarantee compliance with local safety standards.

The TWPro MB Increaser is compatible with solid fuel appliances like woodstoves, gas coal effect fires, oil boilers, and gas boilers.

The increaser features an outer skin made from 304 stainless steel and an inner skin from 316 stainless steel, both 0.4mm thick. It's also coated with a high temperature black finish and insulated with compressed rockwool.

The increaser should be kept at a distance of at least 50mm from any combustible materials like wood or plasterboard.

Yes, the TWPro MB Increaser is HETAS approved and also CE marked.

The increaser is installed using a Locking Band that secures the parts together. Ensure you maintain the recommended 50mm distance from combustibles.

The designation numbers for this increaser are EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 P1 W V2 L50040 O20.

The insulation of the TWPro MB Increaser has a density of 200kg/m3, which ensures efficient heat retention.

 

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