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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...
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 installation with compatible accessories for a truly customised flue setup. Less...
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In Stock
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.
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.
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
Material
316L Stainless Steel
Thickness
1mm
Diameter Transition
175mm to 200mm
Temperature Rating
Up to 600u00b0C (T600)
Fuel Compatibility
Wood (<20% moisture), Oil, Gas, Smokeless Coal
Standards
CE / HETAS compliant
System Compatibility
Single 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.
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Read our buyers guide for this Screw-FIX Increaser, 1mm - Ø 175-200mm
Comprehensive Buyers Guide for the Screw-FIX Increaser
When it comes to ensuring the safety and efficiency of your flue system, choosing the right components is critical. The Screw-FIX Increaser, crafted from durable 316L stainless steel, is designed to transform the diameter of your flue from 175mm to 200mm, providing you with a secure and compliant connection between your rigid single wall system and a flexible MI-FLEX flue liner.
What is the Screw-FIX Increaser?
The Screw-FIX Increaser is a specialised adapter that plays a key role in flue system installations. It is specifically engineered to meet the needs of modern flue systems by facilitating a seamless transition between different flue types. Manufactured from high-grade 316L stainless steel, this increaser withstands high temperatures (up to 600°C) and is ideal for a variety of fuel types, including wood (with less than 20% moisture), oil, gas, and smokeless coal. With its robust design, it not only ensures a secure connection but also contributes to the overall safety and longevity of the flue system.
Why is Compliance Important?
One of the most important factors when selecting flue system components is compliance with Building Regulations Document J. This document mandates that certain products must be installed within a masonry chimney, and the Screw-FIX Increaser meets these strict requirements. By utilising this increaser, you can be confident that your installation complies with all legal standards, safeguarding your property and ensuring reliable performance. Compliance is not just about adhering to rules—it also means that your system will function efficiently and safely, reducing the risk of future issues.
Features and Benefits
- High-Quality Materials: The use of 316L stainless steel ensures that the increaser is durable, resistant to corrosion, and capable of withstanding extreme temperatures. This results in a longer lifespan and a reliable performance over years of use.
- Secure Diameter Transition: By increasing the flue diameter from 175mm to 200mm, the product guarantees a tight and secure fit between the rigid and flexible sections of the system, minimising the risk of leaks and ensuring safety.
- Versatile Fuel Compatibility: Whether your heating system uses wood, oil, gas, or smokeless coal, the Screw-FIX Increaser is engineered to maintain performance across all these fuel types.
- Easy Installation and Maintenance: Designed for smooth integration into your existing system, the increaser allows for hassle-free installation. Regular maintenance, performed by HETAS registered professionals, ensures that your system remains unclogged and operates at peak efficiency.
- Optional Accessories: To further enhance the sealing and security of your flue system, optional accessories such as fire cement, ceramic rope, tape, and high-temperature sealant can be incorporated. These additions provide extra assurance against leaks and improve the overall performance of your installation.
Installation Guidelines and Best Practices
It is crucial that the Screw-FIX Increaser is installed correctly to maximise its benefits. The entire increaser must be situated within a masonry chimney. Utilize high-temperature sealants during installation to create a gas-tight seal, thereby preventing the flexible liner from any exposure. Adhering to these guidelines will not only comply with Building Regulations Document J but also ensure that your system is as safe and efficient as possible. Maintenance should be routine; for solid fuel systems, sweeping at least twice a year is recommended, and all systems should undergo an annual inspection by a certified chimney sweep.
Addressing Common Concerns
Installation Complexity: Many customers worry that installing transition components can be complex. However, because the Screw-FIX Increaser is designed to integrate seamlessly with existing flue systems, the process is straightforward when carried out by a professional.
Long-Term Reliability: Investing in a high-quality component like the Screw-FIX Increaser ensures long-term benefits. The durable construction and robust design mean that your flue system not only complies with regulations today but will continue to perform reliably in the future.
Optional Accessories: For those looking to enhance their installation further, it is worth considering the various optional accessories available. These items are designed to work in conjunction with the Screw-FIX Increaser to provide additional security and efficiency. Research into these products or a consultation with a professional can help tailor the installation to your specific needs.
Making the Decision
Choosing the correct flue system components is a critical investment in the safety and efficiency of your home. The Screw-FIX Increaser is a top choice due to its high-grade materials, regulatory compliance, and ease of installation. With its ability to handle various fuel types and its robust, secure design, the product stands out as a reliable solution for both residential and commercial installations.
We understand that purchasing components for your flue system is a significant decision. This guide aims to provide you with thorough, transparent information to help you make an informed choice that meets your specific requirements. With National Flues, you are assured of both quality and after-sales support, ensuring that your flue system operates safely and efficiently for years to come.
If you have further questions or need personalised advice, please do not hesitate to contact our expert team. They are on hand to offer guidance on both the installation process and the selection of optional accessories to optimise your system.
Add to cart today or call 01670 206 999.
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.
Upgrade your flue system now for reliable performance and peace of mind – order today.