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Joiner - Ø 250 (20-250-J)

National Flues presents the Joiner Ø 250 – a superior accessory for connecting MI-FLEX flexible flue liners in multi-fuel chimney systems. This high-quality joiner is essential for any installation requiring the seamless joining of chimney flue sections, making it an ideal choice for wood, smokeless coal, oil, and more. Read more...
Joiner - Ø 250
IN STOCK
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Now only £99.99
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At a Glance

  • Designed for seamless joining of MI-FLEX multi-fuel flue liners
  • Crafted from high-quality 316L stainless steel with a natural finish
  • Supports multi-fuel applications including wood (with < 20% moisture), smokeless coal, oil, and gas (except gas liners)
  • Endorsed for high temperature use up to 600°C (T600 designation)
  • Complies with Building Regulations Document J for masonry-enclosed chimneys

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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.
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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.

Free Delivery Over £100: Orders over £100 are free delivery (call us if delivery is required outside the mainland UK).

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Have Questions?
Phone: 01670 206999
Email: sales@nationalflues.com

The Joiner Ø 250 from National Flues is an essential accessory for the seamless installation of MI-FLEX 316 and 904 flexible flue liners, creating a full chimney system. Ideal for multi-fuel appliances, it supports applications up to 600°C (T600). Use it for wood with less than 20% moisture, smokeless coal, gas, and oil.

Note: This joiner is not suitable for gas liners and should only be used when the chimney liner length exceeds the maximum available flex length. Ensure your chimney is masonry-enclosed, never within timber or plasterboard boxing, to comply with Building Regulations Document J.

SKU: 20-250-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.

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Technical Specifications
SKU20-250-J
Material316L Stainless Steel
Colour FinishNatural / Stainless Steel
SystemMI-FLEX Accessories MF20
ApprovalsHETAS / CE
Temperature RatingUp to 600°C (T600)
Fuel CompatibilityWood (<20% moisture), Smokeless Coal, Oil, Gas (Note: Not suitable for gas liners)
Installation RequirementMasonry-enclosed chimney (not for timber or plasterboard boxing)
Before installation, verify that your chimney is masonry-enclosed as required by Building Regulations Document J. The Joiner Ø 250 must be used only when the flue liner length exceeds the maximum available flexible length. It is vital to note that this joiner is not designed for use with gas liners. Prior to use, ensure that all connections are secure and that the joiner is installed in accordance with the manufacturer’s guidelines. Always consult a HETAS registered professional for chimney sweeping and maintenance to guarantee safety and compliance.

The Joiner Ø 250 is designed for use with MI-FLEX 316 and 904 flexible flue liners.

No, the Joiner Ø 250 should not be used on gas liners. It is meant for multi-fuel applications.

The Joiner Ø 250 is suitable for use on appliances with temperatures up to 600°C (T600 designation).

The joiner is suitable for wood with less than 20% moisture, smokeless coal, gas, and oil.

Flue liner systems should be inspected and cleaned at least once a year. For solid fuel appliances, it’s recommended to sweep the chimney twice a year.

No, Building Regulations Document J stipulates that flue liners must be enclosed within a masonry chimney. Timber or plasterboard enclosures are not acceptable.

Chimney sweeping must be carried out by a competent person, ideally a HETAS registered sweep for solid fuel applications.

 

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