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TWPro MB - Single Wall to Twin Wall Increaser - Ø 175-Ø 200 (37-175-002)

National Flues presents the TWPro MB - Single Wall to Twin Wall Increaser, a premium chimney adapter designed to effortlessly bridge 175mm single wall pipes and 200mm twin wall insulated chimneys. This high-performance increaser is perfect for a range of heating solutions including wood stoves, oil and gas boilers, and coal effect fires. Read more...
TWPro MB - Single Wall to Twin Wall Increaser - Ø 175-Ø 200
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Now only £33.99
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At a Glance

  • Premium dual stainless steel construction (316L inner, 304 outer with high-temperature black finish)
  • Suitable for solid fuel, gas, and oil appliances
  • HETAS Approved and CE marked for safety and compliance
  • Includes a secure Locking Band for easy installation
  • Provides 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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Have Questions?
Phone: 01670 206999
Email: sales@nationalflues.com

The TWPro MB - Single Wall to Twin Wall Increaser is an essential component for your chimney flue system, especially when upgrading from a 175mm single wall pipe to a 200mm twin wall insulated chimney. Designed for use with solid fuel, gas, and oil appliances, including wood stoves, gas coal effect fires, and boilers, this increaser ensures optimal performance and safety. Constructed with a durable outer skin of 304 grade stainless steel at 0.4mm thickness, it features a high-temperature black finish for added durability.

The inner skin, made from 316 grade stainless steel, also at 0.4mm thickness, ensures longevity. The rockwool insulation boasts a density of 200kg/m³, providing excellent thermal protection. Fully welded parts and a safe distance of 50mm to combustibles make installation straightforward and secure.

The TWPro MB Increaser is HETAS Approved and CE marked, with designation numbers EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 P1 W V2 L50040 O20, ensuring it meets the highest safety and quality standards. Installation is simplified with the included Locking Band, ensuring a secure and reliable fit.

SKU: 37-175-002

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
SKU37-175-002
SizeØ 175 to Ø 200
Inner Construction316L Stainless Steel (0.40mm thick)
Outer Construction304 Stainless Steel (0.40mm thick, High Temperature Black Coated)
InsulationRockwool with density of 200kg/m³
ApprovalsHETAS / CE
Distance To Combustibles50mm
System CompatibilityTWPro Black
Designation NumbersEN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 P1 W V2 L50040 O20
Installation of the TWPro MB Increaser is designed to be straightforward and safe. Ensure that a clearance of 50mm is maintained between the flue and any combustible material such as wood or plasterboard. The increaser comes with an integrated Locking Band which must be securely fastened during installation. Prior to fitting, double-check that the system meets local building regulations and standards. For optimal performance, ensure that each connection is tight and mechanically sound. This will not only contribute to the system’s efficiency but also guarantee the high safety standards the product is known for.

The TWPro MB Increaser is suitable for solid fuel, gas, and oil appliances, including wood stoves, gas coal effect fires, oil boilers, and gas boilers.

The outer skin is 304 grade stainless steel with a high-temperature black finish, and the inner skin is 316 grade stainless steel. The insulation is compressed rockwool with a density of 200kg/m³.

Yes, the TWPro MB Increaser is HETAS Approved and CE marked, meeting stringent safety and performance standards.

A safety distance of 50mm should be maintained from the outside of the flue to any combustible materials like wood or plasterboard.

Installation is easy with the included Locking Band, which secures the parts together. Just ensure a 50mm clearance from combustibles.

This designation indicates compliance with specific European standards for chimney components, ensuring they meet high safety, efficiency, and durability criteria.

Absolutely. This increaser is designed to be highly durable and versatile, suitable for both small domestic installations and larger, more complex systems.

 

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