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Screw-FIX Long Tail Increaser - Ø 125-150mm (25-125-MRLT)

National Flues presents the durable Screw-FIX Long Tail Increaser - Ø 125-150mm, a top-notch 316L stainless steel adaptor designed for seamless connections in chimney systems. This essential flue accessory bridges single wall flue systems with MI-FLEX flexible liners, supporting a range of fuel types including wood, oil, gas, and smokeless coal. Read more...
Now only £43.99
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At a Glance

  • High-grade 316L stainless steel construction
  • Compatible with wood, oil, gas, and smokeless coal appliances
  • Designed for secure, gas-tight transitions between flue systems
  • Compliant with Building Regulations Document J and CE/HETAS standards
  • Ideal for use with MI-FLEX flexible flue liners

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 Screw-FIX Long Tail Increaser - Ø 125-150mm is a high-quality, 316-grade stainless steel adaptor designed for seamless transitions between single wall connecting flue systems and MI-FLEX flexible flue liners. Ideal for use with various fuels such as wood (with less than 20% moisture), smokeless coal, gas, and oil, this increaser supports appliance temperatures up to 600°C (T600). Compliant with Building Regulations Document J, it ensures installation must be fully enclosed within a masonry chimney.

Creating a gas-tight seal is crucial; hence, it is advisable to use fire cement, ceramic rope or tape, or high-temperature sealant. This increaser also facilitates easy provisions for maintenance and chimney sweeping, which are essential to keep your system in top shape. Always opt for competent professionals for sweeping to avoid damage to the flue system.

SKU: 25-125-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.

Technical Specifications
SKU25-125-MRLT
DesignationBSEN 1856-2 T600 N1 W V2 L50012 G
Material316L Stainless Steel
Colour FinishStainless Steel / NATURAL
SystemMI-FLEX Accessories MF20
FuelsWood, Oil, Gas, Smokeless coal
Temperature Rating600°C
ComplianceCE / HETAS, Building Regulations Document J
Ensure the flexible flue liner is fully enclosed within a masonry chimney in compliance with Building Regulations Document J. Use fire cement, ceramic rope or tape, or a high-temperature sealant to create a gas-tight seal. Always select a competent professional for installation and annual chimney sweeping to avoid any issues. Avoid using chemical cleaners or mild steel tools on stainless steel components to ensure longevity.

The Screw-FIX Long Tail Increaser is designed to connect single wall flue systems to flexible flue liners, ensuring a smooth transition and a secure, gas-tight seal.

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

To ensure a gas-tight seal, it is recommended to use fire cement, ceramic rope or tape, or high-temperature sealant.

Yes, per Building Regulations Document J, the flexible flue liner must be installed fully enclosed within a masonry chimney. Any form of timber or plasterboard boxing is not acceptable.

It’s recommended to have the chimney system cleaned and inspected at least once a year. However, for solid fuel appliances, sweeping should occur at least twice a year – at the end of the heating season and before the next heating season starts.

No, chemical cleaners and mild steel tools should not be used for sweeping stainless steel chimneys. Always opt for professional cleaning.

While it's possible for those experienced with chimney installations, it's highly recommended to hire a competent professional to ensure all components are correctly installed and comply with building regulations.

 

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