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Increasing MI-FLEX Adaptor - Ø 125-Ø 175 (20-125-MRD)

Discover the superior Increasing MI-FLEX Adaptor by National Flues – a robust and reliable stainless steel solution designed to bridge the gap between ridged single wall flue systems and MI-FLEX flexible liners. Read more...
Now only £68.99
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At a Glance

  • 6mm 316 stainless steel construction
  • Increases flue diameter from Ø125mm to Ø175mm (50mm increase)
  • Durable, high-temperature resistance up to 600°C (T600 designation)
  • Compatible with wood (<20% moisture), oil, gas, and smokeless coal
  • BSEN 1856-2 T600, HETAS & CE compliant; Building Regulations Document J approved

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.
  • Operational Efficiency: We have streamlined processes to reduce overhead.

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 Increasing MI-FLEX Adaptor - Ø125mm to Ø175mm from National Flues is a must-have for any chimney setup. This 0.6mm 316 stainless steel adaptor serves as a transitional joint that effortlessly connects a ridged single wall flue system to MI-FLEX flexible flue liners. Designed to boost performance and improve system integrity, this adaptor increases the diameter by 50mm, accommodating a variety of fuel types including wood (with moisture <20%), smokeless coal, gas, and oil.

Engineered to withstand temperatures up to 600°C (T600 designation), it ensures a gas-tight seal with the use of fire cement, ceramic rope, or high-temperature sealant. Building Regulations Document J compliance guarantees safe and effective installation within a masonry chimney. Regular maintenance, such as sweeping and inspections done by a competent person, ensure longevity and optimal performance.

SKU: 20-125-MRD

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.

Technical Specifications
Material316L Stainless Steel
Thickness0.6mm
Diameter ConversionØ125mm to Ø175mm
Temperature RatingUp to 600°C (T600)
Fuel CompatibilityWood (<20% moisture), Oil, Gas, Smokeless Coal
CertificationsBSEN 1856-2 T600, HETAS, CE
SystemMI-FLEX Accessories MF20
ComplianceBuilding Regulations Document J
Install the Increasing MI-FLEX Adaptor within the confines of an existing masonry chimney. Ensure that no flex element is visible by fitting the adaptor securely inside the chimney structure. Use fire cement, ceramic rope, or a high-temperature sealant to achieve a gas-tight seal, preventing any leakage of exhaust gases. For safety, always adhere to the manufacturer’s guidelines and consult a certified installer if unsure. Regular maintenance, including routine sweeping by a HETAS registered professional, is essential to maintain peak performance and system safety.

The adaptor is made from 0.6mm 316 stainless steel, providing high durability and resistance to corrosion under extreme temperatures.

Yes, the adaptor meets Building Regulations Document J requirements, ensuring it can be safely enclosed within a masonry chimney.

The adaptor is suitable for use with wood (with less than 20% moisture content), smokeless coal, gas, and oil.

The adaptor should be installed within the confines of an existing masonry chimney, ensuring no flex is visible. Use fire cement, ceramic rope, or high-temperature sealant to achieve a gas-tight seal.

Regular sweeping and maintenance are essential. It is recommended to sweep chimneys serving solid fuel appliances twice a year, and at least once annually for other systems.

No, chemical cleaners and mild steel tools should not be used. Use appropriate methods and tools to avoid damaging the stainless steel components.

You can find a list of HETAS registered sweeps at www.hetas.co.uk, ensuring qualified professionals conduct the chimney sweeping.

 

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