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904L Mi-FLEX 150mm x 40m COIL (36Z-150-40)

Discover the premier 904L Mi-FLEX 150mm x 40m COIL flue liner from National Flues, engineered to deliver industry-leading performance in multi-fuel applications. This high-grade, double-skinned flue liner is ideal for masonry chimneys and is backed by a lifetime warranty when installed with Screw-FIX accessories. Read more...
904L Mi-FLEX 150mm x 40m COIL
IN STOCK
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Now only £1,928.99
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At a Glance

  • Manufactured from 904L grade stainless steel for exceptional durability
  • Double-skinned design with 0.105mm thick inner and outer layers
  • Multi-fuel capability including gas, oil, coal, coke, cured dry logs, cured dry peat, and approved smokeless fuels
  • CE approved and HETAS listed for industry-standard safety and performance
  • Lifetime warranty when installed with Screw-FIX accessories

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 904L Mi-FLEX 150mm x 40m COIL is a versatile and durable flue liner designed to fit masonry chimneys. Manufactured with high-grade 904L stainless steel, this double-skinned flexible liner is built to last. It boasts a smooth inner liner and a convoluted outer skin, each 0.105mm thick for enhanced durability.

Featuring a unique quattrolock seal, the liner is resistant to corrosion and is CE approved and HETAS listed. Perfect for burning gas, oil, coal, coke, cured dry logs, cured dry peat, and approved smokeless fuels, this flue liner ensures optimal performance and safety. The product comes with a lifetime warranty when installed with Screw-FIX accessories.

SKU: 36Z-150-40

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
SKU36Z-150-40
Dimensions150mm diameter x 40m coil
Material904L stainless steel (inner and outer layers at 0.105mm thickness)
Fuel TypesGas, Oil, Coal, Coke, Cured Dry Logs, Cured Dry Peat, Approved Smokeless fuels
ApprovalsCE approved, HETAS listed
ManufactureMi-Flues Ltd, Single Strip construction
SeamOmega-Lock
WarrantyLifetime (when installed with Screw-FIX accessories)
For best results, the 904L Mi-FLEX liner should be installed from the top of the chimney. Begin by verifying the liner’s compatibility with your chimney by pulling a small section down before a full installation. Secure a string to the Nose Cone (sold separately) ensuring the arrow indicators point upward to maintain the correct gas flow. As you feed the liner into the chimney, have an assistant guide it from above. Once the liner is fully positioned, remove the Nose Cone and proceed with final fixing using the recommended Screw-FIX accessories. Always refer to the manufacturer's installation manual for detailed guidance and safety warnings.

904L grade stainless steel is highly resistant to corrosion and extreme temperatures, making it ideal for multi-fuel applications. It ensures longevity and performance in demanding conditions.

Yes, this flue liner is suitable for burning gas, oil, coal, coke, cured dry logs, cured dry peat, and approved smokeless fuels.

To ensure a proper fit, pull a small section of the liner down your chimney before installation. This checks the compatibility of the liner's diameter with your chimney.

The flue liner should always be installed from the top of the chimney. Secure a string to the Nose Cone (sold separately), ensuring the arrows point upwards for correct gas flow. Pull the liner down the chimney using the string, with someone feeding it from the top. Finally, remove the Nose Cone once the liner is in place.

It is recommended to sweep and maintain chimneys serving solid fuel appliances at least once a year or as frequently as necessary to ensure safety and performance.

Yes, the 904L Mi-FLEX flue liner is CE approved and listed by HETAS, ensuring it meets high safety and performance standards.

The flue liner comes with a lifetime manufacturer’s warranty when installed with Screw-FIX accessories, covering the lifespan of the appliance it is connected to.

 

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