× National Flues
Free Delivery on All Orders Over £100
We have 100% 5 Star Reviews on Trustpilot
Enjoy Our Free Flue Design Service
Delivery To Mainland UK Addresses
Call Our Experts on 01670 206999

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. Explore our range of MI-FLEX accessories to complete your system with precision and reliability.
Joiner - Ø 250
In Stock
Product Thumbnail
Great value at £129.99
including free delivery Give us a call if you find it cheaper and we'll try to price match.

 

Payment Options

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

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: [email protected]

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

Technical Specifications
SKU20-250-J
Material316L Stainless Steel
Colour FinishNatural / Stainless Steel
SystemMI-FLEX Accessories MF20
ApprovalsHETAS / CE
Temperature RatingUp to 600u00b0C (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.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Thursday, May 22nd. Delivery times of products not in our warehouses depend on product availability and shipping. If you need a definitive delivery time give us a call. If you need faster stove or fireplace delivery please also give us a call. We can sometimes 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.

×

Product added

Would you like to keep shopping or head to checkout?

Need the finishing touch? Add our 10m Flex Pack Bundle for under £299.

 

Your recently viewed products:

Joiner - Ø 250

Joiner - Ø 250

View Product
Multiple Payment Options- including Klarna, Clearpay, Mastercard, Visa and Paypal
Free Design Service Click To Call Our Experts