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Screw-FIX Flex Joiner - Ø 80 (25-80-J)

National Flues proudly presents the Screw-FIX Flex Joiner - Ø 80, a top-quality chimney accessory designed for multi-fuel flue systems. Engineered for durability and maximum safety, this MI-FLEX connector is ideal for 316L and 904 flexible flue liners. Read more...
Now only £30.99
Give us a call if you find it cheaper and we'll normally price match.
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At a Glance

  • Securely connects two pieces of multi-fuel flexible flue liner
  • Designed for use with MI-FLEX 316 and 904 linings
  • Withstands high temperatures up to 600°C
  • Constructed from durable 316L stainless steel with a natural finish
  • Fully compliant with Building Regulations Document J
  • Allows easy provision for sweeping and straightforward maintenance

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 Flex Joiner - Ø 80 is an indispensable accessory for connecting two pieces of multi-fuel flexible flue liner. Specifically designed for use with MI-FLEX 316 and 904 flexible flue liners, this joiner ensures a secure and efficient connection, creating a full-system chimney. Compliance with Building Regulations Document J means the liner must be fully enclosed within a masonry chimney, and it is not suitable for non-masonry enclosures such as timber or plasterboard boxing.

This joiner is ideal for appliances operating at temperatures up to 600°C, including those using wood with less than 20% moisture, smokeless coal, gas, and oil. When it comes to installation and maintenance, this product allows for easy provision for sweeping and requires that cleaning and inspections be carried out at least annually by a competent person. For solid fuel applications, biannual sweeping at the start and end of the heating season is recommended to ensure safety and efficiency.

SKU: 25-80-J

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
SKU25-80-J
Product NameScrew-FIX Flex Joiner - Ø 80
Material316L Stainless Steel
Diameter80mm
SystemMI-FLEX Accessories MF25
Temperature RatingUp to 600°C
Colour FinishStainless Steel / NATURAL
FuelsWood, Oil, Gas, Smokeless coal
ApprovalsCE / HETAS
ComplianceBuilding Regulations Document J
Ensure the Screw-FIX Flex Joiner is installed within a masonry chimney; it is not suitable for use on gas liners. The joiner must be fully enclosed within the masonry structure as per Building Regulations Document J. Regular maintenance is critical: arrange for cleaning and inspections at least annually by a competent person, and for solid fuel applications, schedule biannual sweeping at the start and end of the heating season. Always follow manufacturer guidelines to avoid any installation errors that could compromise the safety and efficiency of your chimney system.

The Screw-FIX Flex Joiner - Ø 80 is used to connect two pieces of multi-fuel flexible flue liner, ensuring a secure and efficient chimney system.

No, the Screw-FIX Flex Joiner must not be used on gas liners. It is specifically designed for multi-fuel flue liners.

Yes, the joiner is suitable for appliances operating on wood (with less than 20% moisture), smokeless coal, gas, and oil.

Yes, installation of the Screw-FIX Flex Joiner complies with Building Regulations Document J, which requires that a flexible flue liner be fully enclosed within a masonry chimney.

The joiner is suitable for use on appliances operating up to 600°C (T600 designation).

It is recommended to clean and inspect your chimney system at least once a year. For solid fuel appliances, it's advised to sweep the chimney at least twice a year.

Sweeping and maintenance should be carried out by a competent person. For solid fuel applications, a list of HETAS registered sweeps can be found at www.hetas.co.uk.

 

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