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904L Mi-FLEX 125mm x 44m COIL (36Z-125-44)

The 904L Mi-FLEX 125mm x 44m COIL from National Flues represents a premium flexible flue liner crafted for masonry chimney relining. Made from durable 904L stainless steel, this superior product not only meets rigorous HETAS and CE standards but also offers a lifetime warranty. Read more...
904L Mi-FLEX 125mm x 44m COIL
IN STOCK
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Now only £1,844.99
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At a Glance

  • Double-skinned 904L stainless steel construction (0.105mm inner and outer skins)
  • Flexible design ideal for relining masonry chimneys
  • Multi-fuel compatibility: gas, oil, coal, coke, cured dry logs, cured dry peat, and smokeless fuels
  • HETAS and CE approved for safety and performance
  • Lifetime warranty for peace of mind
  • Designed for optimal airflow and heat efficiency

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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 125mm x 44m COIL is a top-tier double skinned flexible flue liner designed for relining masonry chimneys. Constructed with durable 904L grade stainless steel, both the inner and outer skins measure 0.105mm in thickness, ensuring longevity and performance. The smooth inner liner enhances airflow, while the convoluted outer skin provides added flexibility and strength.

This flue liner accommodates a variety of fuels, including gas, oil, coal, coke, cured dry logs, cured dry peat, and approved smokeless fuels. It carries the essential approvals from HETAS and CE, confirming its high standards. For installation, ensure the liner is fed from the top with arrows pointing upward to align with gas flow.

Secure it with a Nose Cone and string, easing it down the chimney for a perfect fit. Regular maintenance is advised, especially for chimneys serving solid fuel appliances, to keep it functioning optimally.

SKU: 36Z-125-44

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-125-44
Flue Type904L Mi-FLEX 125mm x 44m COIL
Inner Material904L stainless steel, 0.105mm thick
Outer Material904L stainless steel, 0.105mm thick
Fuel CompatibilityGas, Oil, Coal, Coke, Cured Dry Logs, Cured Dry Peat, Smokeless Fuels
ApprovalsHETAS, CE
Manufacture MethodSingle Strip with Omega-Lock seam
WarrantyLifetime
InstallationFed from top, use Nose Cone and string for secure setup
• Begin installation at the top of the chimney, ensuring that the directional arrows on the liner point upwards in line with gas flow. • Gently feed the liner down the chimney using an appropriate Nose Cone and a robust string to guide it securely. • For optimal fit and performance, consider using optional Screw-FIX accessories that can help secure the liner effectively. • Make sure to secure the liner at intervals to prevent sagging or misalignment. • Regularly inspect the installation, especially for chimneys servicing solid fuel appliances, and schedule routine maintenance such as annual sweeping. • If you are opting not to use a suspended cowl, double-check that your chimney pot is in excellent condition or consider its removal for a safer setup.

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

904L grade stainless steel is known for its excellent corrosion resistance, durability, and strength, making it ideal for flue liners exposed to high temperatures and various fuel types.

Installation should be done from the top of the chimney, ensuring the arrows on the liner point upwards. Use a Nose Cone and string to guide the liner smoothly down the chimney, with a colleague assisting from the top.

Yes, it is approved and listed by HETAS and also carries CE approval, guaranteeing it meets high safety and performance standards.

Chimneys serving solid fuel appliances should be swept and maintained at least once a year or more frequently if needed.

Both the inner and outer skins of the flue liner are 0.105mm thick, providing robust protection and flexibility.

If you are not using a suspended cowl, ensure your chimney pot is in good condition. If not, it should be removed from the stack.

 

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