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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. Ideal for various fuels including gas, oil, coal, and smokeless options, this flue liner is engineered for optimal performance, efficiency, and longevity. Experience unmatched quality and robust performance with this essential chimney solution.
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In Stock
£1,364.99
with free delivery
Give us a call if you find it cheaper and we'll try to price match.
At a Glance
Double-skinned 904L stainless steel construction (0.105mm inner and outer skins)
Flexible design ideal for relining masonry chimneys
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“I saved 20% on my purchase compared to other retailers. Exceptional service!” – Jane D.
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.
Fed 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.
Delivery Information +
We work relentlessly to ensure you get your order fast.
Estimated delivery for this product is Tuesday, April 29th.
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 on a retail basis. Give us a call if you find it cheaper and want to buy from us.
Read our review in our 904L Mi-FLEX 125mm x 44m COIL buyers guide
Comprehensive Buyers Guide for the 904L Mi-FLEX 125mm x 44m COIL
When it comes to ensuring the safety, efficiency, and longevity of your chimney system, choosing the right flue liner is crucial. The 904L Mi-FLEX 125mm x 44m COIL has been designed to meet the high demands of modern heating systems, offering a robust solution that accommodates a range of fuel types. In this guide, we will walk you through everything you need to know about this premium flue liner, addressing common questions, detailing the installation process, and explaining the benefits of investing in additional accessories to optimise your setup.
Why Choose the 904L Mi-FLEX Flue Liner?
- Exceptional Durability: Made from top-grade 904L stainless steel, both the inner and outer layers (each at 0.105mm) ensure enhanced resistance to corrosion and damage, even under harsh conditions. This means a longer lifespan and reduced costs in maintenance and replacements.
- Versatility and Multi-Fuel Compatibility: Whether you rely on gas, oil, coal, coke, or even cured dry logs and peat, this flexible liner is engineered to accommodate various fuels safely. This versatility makes it a highly attractive option for both residential and commercial applications.
- Superior Safety Standards: With its HETAS and CE approvals, the 904L Mi-FLEX flue liner meets stringent safety benchmarks, providing you with peace of mind that your chimney system complies with the highest industry standards.
- Lifetime Warranty: A significant marker of quality, the lifetime warranty offered by the manufacturer is a testament to the product's durability and reliability.
- Ease of Installation: The design supports a straightforward installation process, with features such as directional arrows to guide the installation and compatibility with optional accessories to ensure a perfect, secure fit.
Installation Process and Tips
Proper installation is key to maximising the performance of your flue liner. Always start from the top of the chimney, ensuring that the directional arrows on the liner are aligned with the natural upward flow of gases. Utilise the recommended Nose Cone and string to delicately guide the liner down to its proper location. For installations that require a more secure setup, exploring optional accessories like Screw-FIX kits can be extremely beneficial. These accessories help maintain the integrity of the installation, preventing any shifts or misalignments over time. Remember, regular inspections and timely maintenance, especially for chimneys servicing solid fuel appliances, are essential for long-term efficiency.
Optional Accessories for Enhanced Performance
In addition to the high-quality design of the 904L Mi-FLEX flue liner, using complementary accessories can significantly boost its performance and ease of installation. Accessories such as Screw-FIX kits, additional Nose Cones, and durable guide strings are available to help streamline the installation process. These items are designed to work seamlessly with the liner, providing extra security and ensuring a snug fit. They are particularly useful in complex chimney configurations where extra support is needed. Don’t hesitate to search our catalogue for these optional accessories to complement your purchase and achieve a flawless installation.
Addressing Common Concerns
It is natural to have concerns regarding both the longevity and safety of a flue liner. One frequent worry is whether the material can withstand the extreme temperatures and corrosive nature of varied fuels. With its dual-layer design using 904L stainless steel – renowned for its high resistance to stress and wear – this flue liner is built to excel. Another common query relates to the installation process. While the procedure might seem complex, detailed guidelines and optional accessories have been provided to ensure a smooth and safe setup. Moreover, the lifetime warranty offers additional assurance, making this liner a valuable long-term investment for your heating system.
Why National Flues?
National Flues has established itself as a trusted name in chimney solutions across the UK. Our commitment to offering products that combine quality, durability, and performance is unwavering. The 904L Mi-FLEX flue liner is backed by years of expertise and customer satisfaction, making it a preferred choice for both retail and trade customers. With a focus on nationwide delivery and exceptional after-sales support, National Flues ensures that you receive not only a top-tier product but also reliable service throughout your purchase and installation journey.
Final Thoughts
In summary, the 904L Mi-FLEX 125mm x 44m COIL is an outstanding solution for those seeking an effective, durable, and flexible flue liner. Its high-quality construction, multi-fuel compatibility, and compliance with strict safety standards make it a wise investment. Whether you are an experienced installer or engaging in your first chimney relining project, the additional optional accessories can further enhance the installation experience and secure a flawless, long-lasting result. This comprehensive buyers guide aims to address any uncertainties and encourages you to take the final step towards a safe and efficient chimney system.
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Ensure flawless performance and longevity – secure your 904L Mi-FLEX flue liner today!
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