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Single Wall to Twin Wall Increaser Ø 200 - Ø 250 (2-200-002)

National Flues presents the Single Wall to Twin Wall Increaser Ø 200 - Ø 250, a premium universal adaptor designed for seamless chimney and flue system upgrades. Ideal for woodstoves, oil and gas boilers, and other combustion appliances, this stainless steel increaser is engineered to meet strict safety standards. Read more...
Single Wall to Twin Wall Increaser Ø 200 - Ø 250
IN STOCK
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Now only £36.99
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At a Glance

  • Seamless connection between single wall and twin wall flue systems
  • Robust stainless steel construction (304 outer, 316L inner)
  • High-density 200kg/m3 rockwool insulation for enhanced thermal efficiency
  • HETAS approved and CE marked for safety
  • Easy installation with included locking band
  • Compatible with wood, oil, gas, and low sulphur coal 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.

We Won't Be Beaten On Price

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.
  • Bulk Purchasing Power: We sell a lot, so we can negotiate better rates with suppliers, passing the savings directly to you.
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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).

“I saved 20% on my purchase compared to other retailers. Exceptional service!” – Jane D.

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

The Single Wall to Twin Wall Increaser Ø 200 - Ø 250 is an essential component for connecting single wall to twin wall flue systems, ideal for various solid fuel and gas/oil appliances such as woodstoves, gas coal effect fires, oil and gas boilers. Constructed with a robust outer skin of 304 grade stainless steel and an inner lining of 316 grade stainless steel, each 0.4mm thick, it ensures long-lasting performance. The insulation comprises densely packed (200kg/m3) compressed rockwool, providing superior thermal efficiency and safety.

All parts are meticulously fully welded. With a distance requirement of 50mm to combustibles, this increaser meets the highest safety standards. It's HETAS approved and CE marked, complying with EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20 designations.

Easy installation is guaranteed with the included locking band, making this adaptor a practical, reliable addition to your chimney flue system.

SKU: 2-200-002

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
SKU2-200-002
Product NameSingle Wall to Twin Wall Increaser Ø 200 - Ø 250
Outer Material304 Stainless Steel - 0.40mm thick
Inner Material316L Stainless Steel - 0.40mm thick
InsulationDensely packed compressed rockwool (200kg/m3)
ApprovalsHETAS / CE
ComplianceEN1856-1 T600 N1 W V2 L50040 G50, EN1856-1 T200 W V2 L50040 O20
Compatible AppliancesWood, Oil, Gas, Low sulphur coal
Distance To Combustibles50mm
Accessories IncludedLocking band
Before installation, ensure that the flue system components are clean and free from obstructions. Begin by aligning the Single Wall to Twin Wall Increaser between your existing single wall pipe and the twin wall system, ensuring that all joints are firmly secured. Maintain a minimum 50mm clearance from any combustible materials. Use the included locking band to fasten the connection securely. Follow all manufacturer guidelines and consult the installation manual for any specific instructions or warnings related to your appliance.

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

The outer skin is made from 304 grade stainless steel, and the inner skin is made from 316 grade stainless steel, both with a thickness of 0.4mm.

Yes, the increaser uses high-density (200kg/m3) compressed rockwool insulation to ensure thermal efficiency and safety.

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

Yes, installation is straightforward. The parts are secured together using the included locking band.

Absolutely, it is HETAS approved, CE marked, and complies with designations EN1856-1 T600 N1 W V2 L50040 G50 and EN1856-1 T200 W V2 L50040 O20.

The main purpose is to act as a seamless adaptor, connecting single wall flue pipes to twin wall flue systems while ensuring a smooth and secure transition.

 

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