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Increasing MI-FLEX Adaptor - Ø 150-Ø 200 (20-150-MRD)

National Flues presents the Increasing MI-FLEX Adaptor, a high-quality, 316L stainless steel solution designed to ensure a secure and flawless connection between rigid single wall flue systems and MI-FLEX flexible liners. Read more...
Increasing MI-FLEX Adaptor - Ø 150-Ø 200
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Now only £73.99
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At a Glance

  • Made from premium 316L stainless steel (0.6mm) for enduring performance
  • Increases flue size from Ø 150 mm to Ø 200 mm for a seamless transition
  • Suitable for multi-fuel systems including wood (with less than 20% moisture), gas, oil and smokeless coal
  • Withstands temperatures up to 600°C (T600 rating) ensuring high heat tolerance
  • Fully compliant with UK Building Regulations and certified approvals (HETAS / CE, BSEN 1856-2)
  • Designed for integration with rigid single wall flue systems and MI-FLEX flexible liners
  • Installation optimised for use within masonry chimneys to secure safe operation

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Phone: 01670 206999
Email: sales@nationalflues.com

The Increasing MI-FLEX Adaptor Ø 150-Ø 200 is an essential accessory for your flue installation needs. Crafted from durable 0.6mm 316 stainless steel, this adaptor ensures a seamless connection between your rigid single wall flue system and MI-FLEX 316 or 904 flexible flue liners. This specific adaptor increases the flue size by 50mm, transitioning from Ø 150mm to Ø 200mm smoothly.Designed for multi-fuel flexibility, the MI-FLEX Adaptor can withstand temperatures up to 600°C (T600 designation) and is suitable for use with wood (<20% moisture), smokeless coal, gas, and oil appliances.

Adhering to UK Building Regulations Document J, it is vital that these adaptors are installed completely within a masonry chimney to ensure safety and efficiency.Bottom fixings must be used to secure the connection, with provisions for a gas-tight seal via fire cement, ceramic rope, or high-temperature sealant. This will ensure no flexible liner is exposed externally. Maintenance is straightforward but essential; chimneys must be swept by a competent person, preferably a HETAS registered sweep, at least annually or more frequently for solid fuel appliances.

Proper maintenance keeps your system performing efficiently and safely year-round.

SKU: 20-150-MRD

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
Material316L Stainless Steel (0.6mm thickness)
DimensionsIncreases flue diameter from Ø 150 mm to Ø 200 mm
Temperature Rating600°C (T600)
Compatible FuelsWood (<20% moisture), Oil, Gas, Smokeless Coal
CertificationsHETAS, CE, BSEN 1856-2
System CompatibilityRigid Single Wall & MI-FLEX Flexible Flue Liners
Installation RequirementFully enclosed in a masonry chimney with bottom fixings and gas-tight sealing using high-temperature sealant options
For optimal performance and adherence to UK Building Regulations, the Increasing MI-FLEX Adaptor must be installed entirely within a masonry chimney. Begin by ensuring that the adaptor is correctly positioned to facilitate a smooth transition between the rigid single wall flue system and the flexible MI-FLEX liner. Bottom fixings are essential to secure the connection. Use a gas-tight sealing method – options include fire cement, ceramic rope, or high-temperature sealant – to ensure no part of the flexible liner is exposed externally. It is strongly recommended that installation is carried out by a qualified professional familiar with masonry chimney systems and the specific requirements of flue installations. Regular maintenance, including annual inspections and cleaning by a HETAS registered professional, is crucial in maintaining the system’s safety and efficiency.

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

It can withstand temperatures up to 600°C (T600 designation), making it suitable for a variety of fuel types.

The adaptor should be installed entirely within a masonry chimney, with provisions for a gas-tight seal using fire cement, ceramic rope, or high-temperature sealant.

Regular chimney sweeping by a competent person, such as a HETAS registered sweep, at least annually. Twice a year is recommended for solid fuel appliances.

No, UK Building Regulations require that the flexible flue liner and its components be enclosed within a masonry chimney.

Installation should be performed by a professional to ensure it meets all safety and regulatory standards.

You can find a list of HETAS registered sweeps for solid fuel applications at www.hetas.co.uk.

 

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