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Screw-FIX Top Hat Adaptor - Ø 80 (25-80-THA)

National Flues offers the Screw-FIX Top Hat Adaptor - Ø 80, a premium accessory designed to secure MI-FLEX flue liner systems. This high-performance adaptor ensures safe, compliant, and efficient chimney installations, making it an indispensable component for wood, oil, gas, and smokeless coal heating applications.
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£32.49
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At a Glance

  • Designed for MI-FLEX 316 and 904 flexible flue liners, ensuring a secure, gas-tight transition
  • Withstands temperatures up to 600°C, suitable for wood (<20% moisture), oil, gas, and smokeless coal
  • Constructed from durable 316L stainless steel for long-lasting performance
  • Complies with Building Regulations Document J for safe chimney systems
  • Facilitates easy maintenance and cleaning when installed correctly

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Have Questions?
Phone: 01670 206999
Email: [email protected]

The Screw-FIX Top Hat Adaptor - Ø 80 is a versatile accessory meticulously crafted for seamless integration with MI-FLEX 316 and 904 flexible flue liners. This adaptor plays a critical role in ensuring a full chimney system is achieved when installed according to Building Regulations Document J. It is designed for use with a variety of appliances, including wood (less than 20% moisture), smokeless coal, gas, and oil, all of which can operate at temperatures up to 600°C (T600 designation).

The adaptor must be entirely enclosed within a masonry chimney, as non-masonry enclosures such as timber or plasterboard are not acceptable. For installation, the bottom fixing must be secured both to the connecting flue below and the flexible liner above to form a gas-tight seal, using appropriate materials like fire cement, ceramic rope, or high-temperature sealant. The unit also facilitates routine maintenance and cleaning, which should ideally be conducted by a HETAS registered professional, especially for solid fuel applications.

SKU: 25-80-THA

Technical Specifications
SKU25-80-THA
Sizeu00d8 80mm
Material316L Stainless Steel
Temperature RatingUp to 600u00b0C
SystemMI-FLEX 316 and 904 flexible flue liners
ApprovalsCE, HETAS
Fuel CompatibilityWood (<20% moisture), Oil, Gas, Smokeless Coal
Install the adaptor securely at the base of the chimney beneath the register plate. Use high-quality fire cement, ceramic rope, or a high-temperature sealant to achieve a gas-tight seal between the connecting flue and the flexible liner. It is essential that the adaptor is entirely enclosed within a masonry chimney; non-masonry enclosures such as timber or plasterboard are not acceptable. For optimal safety and regulatory compliance, routine maintenance and cleaning should be performed by a HETAS registered professional.

It is suitable for use with wood (less than 20% moisture), smokeless coal, gas, and oil appliances, operating at temperatures up to 600°C.

It should be installed at the base of the chimney beneath the register plate, fully enclosed within a masonry chimney.

Ensure a gas-tight seal using fire cement, ceramic rope, or high-temperature sealant, and secure it properly to the connecting flue and the flexible liner.

The system should be cleaned and inspected at least once a year, ideally twice for solid fuel appliances, especially at the start and end of the heating season.

No, it must be completely enclosed inside a masonry chimney as non-masonry enclosures like timber or plasterboard are not acceptable.

Maintenance should be carried out by a competent person, preferably a HETAS registered professional for solid fuel applications.

A gas-tight seal prevents potentially dangerous gases from escaping the chimney system, ensuring safe and efficient operation of the flue system.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Wednesday, April 30th. 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 Screw-FIX Top Hat Adaptor - Ø 80 buyers guide

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