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Screw-FIX Increaser, 1mm - Ø 175-200mm

Incorporate our high-quality Screw-FIX Increaser into your MI-FLEX flue system for a durable and compliant solution. National Flues delivers top-tier, stainless steel flue components designed to provide a seamless transition between rigid single wall systems and flexible liners. Enhance your install... More...
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At a Glance

  • - 316L stainless steel construction for enhanced durability
  • - Transitions flue diameter from 175mm to 200mm for a secure fit
  • - Compliant with Building Regulations Document J
  • - Suitable for wood (with <20% moisture), oil, gas, and smokeless coal appliances
  • - Designed for seamless integration with MI-FLEX liners and easy maintenance
Now only £66.99
Including VAT Buy with confidence. If you find this cheaper within 48 hours of checkout, we'll refund the difference.

 

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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.
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  • 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.

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

The Screw-FIX Increaser, 1mm thick and sized at Ø 175-200mm, is an essential component for flue system installations. This 316 stainless steel adapter acts as a transitional joint, seamlessly connecting single wall rigid flue systems to the highly flexible MI-FLEX 316 and 904 flue liners. Designed for versatility, it is suitable for solid fuels like wood (moisture content <20%), smokeless coal, gas, and oil, handling temperatures up to 600°C (T600 designation).Building Regulations Document J mandates its installation within masonry chimneys, prohibiting non-masonry enclosures such as timber or plasterboard boxing. The bottom fixings ensure a gas-tight seal using fire cement, ceramic rope, tape, or high-temperature sealant, preventing the flexible liner from being exposed.Easy provision for maintenance is a key feature, requiring routine cleaning and sweeping by a certified professional, preferably a HETAS registered sweep. Solid fuel systems should be swept at least twice annually to ensure safety and efficiency, removing any blockages or deposits like bird nests.

SKU: 25-175-MR1

Technical Specifications
Material316L Stainless Steel
Thickness1mm
Diameter Transition175mm to 200mm
Temperature RatingUp to 600u00b0C (T600)
Fuel CompatibilityWood (<20% moisture), Oil, Gas, Smokeless Coal
StandardsCE / HETAS compliant
System CompatibilitySingle wall flue systems to MI-FLEX 316/904 flue liners
The Screw-FIX Increaser must be installed entirely within a masonry chimney as required by Building Regulations Document J. For optimal performance and safety, secure the increaser using high-temperature materials such as fire cement, ceramic rope, tape, or a high-temperature sealant. It is essential that installation work is carried out by a certified professional, ideally a HETAS registered sweep, to ensure the highest standards of safety and compliance. Regular maintenance is crucial: solid fuel systems should be serviced at least twice a year, while other systems must receive an annual check. Under no circumstances should the flexible flue liner be exposed during the installation process.

The Screw-FIX Increaser is suitable for wood with less than 20% moisture, smokeless coal, gas, and oil appliances, handling temperatures up to 600°C.

The increaser should be installed entirely within a masonry chimney as per Building Regulations Document J. Non-masonry enclosures like timber or plasterboard are not acceptable.

A gas-tight seal can be achieved using fire cement, ceramic rope or tape, or high-temperature sealant. The connection should be made inside the confines of the existing masonry chimney.

Chimneys should be swept and inspected at least once a year by a competent person, with solid fuel systems recommended for sweeping twice a year. Only specialised tools and no chemical cleaners should be used.

No, the flexible flue liner should not be exposed. The transition should occur entirely within the masonry chimney to ensure safety and compliance.

You can find a list of HETAS registered sweeps at www.hetas.co.uk. It's important to use certified professionals for chimney maintenance.

The Screw-FIX Increaser transitions from a 175mm rigid single wall flue to a 200mm flexible flue liner.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, April 4th. 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. If you find it cheaper within 48 hours, we'll refund the difference.

Read our buyers guide for this Screw-FIX Increaser, 1mm - Ø 175-200mm

National Flues Ltd Verdict

The Screw-FIX Increaser is a top-tier product that ensures a smooth transition from single wall flue systems to MI-FLEX liners. Perfect for various fuels and compliant with Building Regulations, it's a favourite among our trade and retail customers. With reliable nationwide delivery, National Flues ensures you get the best at unbeatable prices.

The Screw-FIX Increaser is used to connect a rigid single wall flue system to a flexible MI-FLEX flue liner, ensuring a seamless and secure transition.

National Flues is a leading supplier of fireplaces and flues across the UK, catering to both retail and trade customers. Renowned for competitive pricing and reliable delivery, we provide high-quality products and top-tier customer service.

 

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