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Long Tail Increasing MI-FLEX Adaptor - Ø 150-Ø 175 (20-150-MRLT)

The Long Tail Increasing MI-FLEX Adaptor for Ø 150-Ø 175 from National Flues is a premium stainless steel chimney component designed for seamless connections between rigid flue systems and MI-FLEX flexible liners. Read more...
Long Tail Increasing MI-FLEX Adaptor - Ø 150-Ø 175
IN STOCK
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Now only £47.99
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At a Glance

  • 6mm 316L stainless steel construction
  • Seamlessly connects rigid single wall and MI-FLEX flexible flue liners
  • Increases flue diameter by 25mm for improved performance
  • Suitable for wood (<20% moisture), smokeless coal, gas, and oil appliances
  • Compliant with Building Regulations Document J, HETAS and CE approved

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Phone: 01670 206999
Email: sales@nationalflues.com

The Long Tail Increasing MI-FLEX Adaptor (Ø 150-Ø 175) is an essential component for your chimney system. Crafted from 0.6mm 316 stainless steel, this adaptor is designed to seamlessly connect a rigid single wall flue system to a flexible MI-FLEX flue liner. It ensures a smooth transition, increasing the flue size by 25mm.

Ideal for use with MI-FLEX 316 and 904 flexible liners, the adaptor complies with Building Regulations Document J, stipulating fully enclosed installation within a masonry chimney. Suitable for appliances up to 600°C, it's perfect for wood (<20% moisture), smokeless coal, gas, and oil. Ensure a gas-tight seal with fire cement, ceramic rope, or high-temperature sealant.

Annual maintenance and sweeping by a competent person, especially for solid fuel systems, are recommended to keep your chimney in optimal condition.

SKU: 20-150-MRLT

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
DimensionsØ 150 to Ø 175, 0.6mm wall thickness
Fuel CompatibilityWood (<20% moisture), Smokeless Coal, Gas, Oil
Temperature RatingUp to 600°C
ApprovalsHETAS, CE
System CompatibilityMI-FLEX 316 & 904 flexible liners
Regulatory StandardCompliant with Building Regulations Document J
Stock StatusIN STOCK (10)
When installing the Long Tail Increasing MI-FLEX Adaptor, first ensure that all surfaces are clean and free of debris. Follow the manufacturer’s guidelines by securely positioning the adaptor between the rigid single wall flue and the MI-FLEX flexible liner. Use high-temperature sealants such as fire cement, ceramic rope, or other approved high-temperature sealants to achieve a gas-tight seal at the connection points. Make sure that the flexible liner is fully enclosed within a masonry chimney as stipulated in Building Regulations Document J. Do not use chemical cleaners or mild steel tools on the stainless steel surfaces. Also, ensure that the bottom fixing into the connecting flue is set securely to prevent any movement. Regular maintenance, including annual inspections and twice yearly sweeping for solid fuel systems, is recommended to guarantee optimal performance and safety.

The primary purpose is to connect a rigid single wall flue system to a flexible MI-FLEX flue liner, ensuring a smooth transition and an increased flue size of 25mm.

Yes, it is suitable for wood with less than 20% moisture, smokeless coal, gas, and oil, accommodating temperatures up to 600°C.

Yes, according to Building Regulations Document J, the flexible flue liner must be fully enclosed within a masonry chimney, and not enclosed in non-masonry materials like timber or plasterboard.

For a gas-tight seal, it is advisable to use fire cement, ceramic rope, or high-temperature sealant to secure the bottom fixing into the connecting flue below and the flexible liner above.

The chimney should be designed for easy sweeping and maintenance. It is recommended to sweep solid fuel appliances at least twice a year and inspect the system annually.

No, chemical cleaners or mild steel tools should not be used to sweep stainless steel chimneys. Engage a HETAS registered sweep for solid fuel applications.

Provisions must be made to ensure the bottom fixing is securely fastened inside the masonry chimney and all connecting points are gas-tight, without any flexible flue liner exposed.

 

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