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Increasing MI-FLEX Adaptor - Ø 150-Ø 175 (20-150-MR)

Discover the premium Increasing MI-FLEX Adaptor from National Flues – a superior solution designed to bridge the gap between a rigid single-wall flue and a MI-FLEX Multi Fuel flexible flue liner. Manufactured from 316L stainless steel, this adaptor guarantees a secure Ø 150 to Ø 175 conversion, delivering outstanding durability and safety. Read more...
Increasing MI-FLEX Adaptor - Ø 150-Ø 175
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At a Glance

  • Constructed from robust 0.6mm 316L stainless steel
  • Designed to transition flue sizes from Ø 150mm to Ø 175mm
  • Ensures a secure, gas-tight seal for safe operation
  • Withstands high temperatures up to 600°C
  • Compliant with Building Regulations Document J and HETAS/CE standards
  • Compatible with a range of fuels including wood, oil, gas, and smokeless coal

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Phone: 01670 206999
Email: sales@nationalflues.com

The Increasing MI-FLEX Adaptor Ø 150 to Ø 175 is an essential component specifically engineered to create a seamless connection from a single wall connecting flue system to MI-FLEX Multi Fuel flexible flue liner. Made from robust 0.6mm 316 stainless steel, this adaptor transitions smoothly, increasing diameter by 25mm, ensuring a gas-tight seal. Designed for use in fully enclosed masonry chimneys as per Building Regulations Document J, it's suitable for high-temperature applications (up to 600°C) and various fuels—wood, smokeless coal, gas, and oil.

Installation requires precise securing using fire cement, ceramic rope, tape, or high-temperature sealant for optimal performance. Maintenance is straightforward, though professional sweeping is recommended, especially for solid fuel applications, with bi-annual cleans advised to maintain chimney health.

SKU: 20-150-MR

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
Material316L Stainless Steel
Thickness0.6mm
Diameter ConversionØ 150mm to Ø 175mm
Maximum Operating Temperature600°C
Fuel CompatibilityWood, Oil, Gas, Smokeless Coal
StandardsHETAS / CE, Building Regulations Document J
Ensure that the adaptor is installed within a fully enclosed masonry chimney in accordance with Building Regulations Document J. Use appropriate high-temperature adhesives such as fire cement, ceramic rope, tape, or high-temperature sealant to secure the adaptor firmly in place. It is essential to verify that no portion of the flexible flue liner is exposed externally, as this could compromise the safety and performance of the system. Regular maintenance is advised; a professional chimney sweep should inspect and clean the system bi-annually, especially if the installation serves a solid fuel appliance. Adhering to these guidelines will help ensure a long-lasting, efficient installation.

The Increasing MI-FLEX Adaptor is used to connect a rigid single-wall flue system to the MI-FLEX Multi Fuel flexible flue liner, increasing the flue size by 25mm.

The adaptor is constructed from 0.6mm thick 316 stainless steel, ensuring durability and high resistance to corrosion.

Yes, the Increasing MI-FLEX Adaptor is suitable for use with wood (with less than 20% moisture), smokeless coal, gas, and oil appliances.

The adaptor should be installed fully enclosed within a masonry chimney, with no flexible flue visible. It's essential to secure it using fire cement, ceramic rope, tape, or high-temperature sealant.

Chimneys connected to solid fuel appliances should be swept at least twice a year. For other fuels, an annual inspection and clean are recommended to ensure proper maintenance and safety.

Yes, Building Regulations Document J states that flexible flue liners must be completely enclosed inside a masonry structure. Enclosures like timber or plasterboard boxing are not acceptable.

Sweeping should be conducted by a competent person. For solid fuel applications, it's advisable to use HETAS registered chimney sweeps.

 

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