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904L Mi-FLEX 100mm x 44m COIL

Experience excellence with the 904L Mi-FLEX 100mm x 44m COIL from National Flues, the premium multi fuel flue liner designed for relining masonry chimneys. Crafted in 904L stainless steel, this flexible flue liner is engineered to deliver superior performance and safety. Whether using gas, oil, or s... More...
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At a Glance

  • - Constructed from high-grade 904L stainless steel for lasting durability
  • - Double-skinned design with a smooth inner surface and convoluted outer layer for optimal gas flow
  • - Manufactured using a single strip with a robust Omega-Lock seam
  • - HETAS approved and CE certified to ensure safety and compliance
  • - Lifetime warranty when installed with Screw-FIX accessories
Now only £1,877.49
Including VAT & Free Delivery Buy with confidence. If you find this cheaper within 48 hours of checkout, we'll refund the difference.

 

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Price Match Guarantee: If you find the same product cheaper within 48 hours, we’ll match it and refund the difference.

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Have Questions?
Phone: 01670 206999
Email: [email protected]

The 904L Mi-FLEX 100mm x 44m COIL is a double-skinned flexible flue liner specifically designed for relining masonry chimneys. Crafted from high-grade 904L stainless steel, this liner boasts a smooth inner surface and a convoluted outer skin, each with a thickness of 0.105mm. The unique construction, featuring a single strip of steel bent at 180 degrees and closely sealed with a quattrolock seam, ensures maximum durability and safety.

Approved by HETAS and CE certified, this flue liner is ideal for use with gas, oil, coal, coke, cured dry logs, peat, and smokeless fuels. Installation is a breeze: simply feed the liner down your chimney from the top, ensuring the arrows indicate the direction of gas flow. Regular maintenance is essential, with an annual sweep recommended for chimneys servicing solid fuel appliances to maintain optimal performance.

SKU: 36Z-100-44

Technical Specifications
SKU36Z-100-44
Dimensions100mm x 44m coil (44m drum)
Material904L stainless steel, 0.105mm thick (inner and outer)
ConstructionDouble-skinned; Single Strip with Omega-Lock seam
ApprovalsHETAS approved, CE certified
Fuel CompatibilityGas, oil, coal, coke, cured dry logs, peat, and smokeless fuels
InstallationFeed from the top of the chimney according to arrow markings
WarrantyLifetime (when installed with Screw-FIX accessories)
Installation is straightforward: start at the top of your masonry chimney and feed the liner down, ensuring the arrows on the liner indicate the correct direction for gas flow. It is recommended to have an assistant at the top of the chimney to guide and secure the liner using a strong, long string. For best results and to validate the lifetime warranty, always use the recommended Screw-FIX accessories. Additionally, note that chimneys servicing solid fuel appliances require an annual sweep to maintain optimal performance and reduce the risk of blockages.

The 904L Mi-FLEX is suitable for use with gas, oil, coal, coke, cured dry logs, cured dry peat, and approved smokeless fuels.

Installation involves feeding the liner down your chimney from the top, ensuring the arrows point upwards for proper gas flow. It's advisable to have someone assist from the top of the chimney while pulling the liner down using a secured string.

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

Chimneys serving solid fuel appliances should be swept at least once a year. Regular maintenance helps ensure optimal performance and longevity.

Yes, the 904L Mi-FLEX is suitable for a gas boiler, along with other compatible fuels listed.

904L stainless steel provides excellent resistance to corrosion and high temperatures, making it ideal for demanding environments like flue systems.

While basic tools will suffice, it's recommended to use a Nose Cone and a strong, long piece of string for guiding the liner into place efficiently.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Wednesday, April 2nd. If you need faster stove or fireplace delivery please give us a call. We can often reduce longer lead times if we pay the carrier £25 for express delivery. Visit our Shipping Information page for more information.

Warranty & Returns +

All our products come with warranties. Mi-Flex offers a lifetime guarantee. Returns for damaged items are covered by insurance; non-damaged returns incur return delivery costs.

Price Match Guarantee +

We will match any price like for like. If you find it cheaper within 48 hours, we'll refund the difference.

Read our buyers guide for this 904L Mi-FLEX 100mm x 44m COIL

National Flues Ltd Verdict

The 904L Mi-FLEX 100mm x 44m COIL is a standout product in its category. With its robust 904L stainless steel construction and easy installation, it’s a top choice for both trade and retail customers. At National Flues, we deliver excellence nationwide, offering unbeatable prices and reliable service.

The 904L Mi-FLEX 100mm x 44m COIL is designed for relining masonry chimneys, suitable for various fuels including gas, oil, and solid fuels.

National Flues is a leading supplier of fireplaces and flues, catering to both retail and trade customers across the UK. Known for competitive pricing and reliable delivery, National Flues ensures a seamless shopping experience with secure online payments and trade account options.

 

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Invest in the 904L Mi-FLEX today for unmatched quality and long-term performance.

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