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Screw-FIX Increaser - Ø 175-200mm (25-175-MR)
National Flues proudly introduces the Screw-FIX Increaser - Ø 175-200mm, a top-tier stainless steel adaptor designed for MI-FLEX flue systems. Engineered for reliability and safety, this product is perfect for connecting a rigid single wall flue system to a flexible flue liner. Whether you are upgrading your fireplace or installing a new heating system, our premium accessory provides a seamless transition while enhancing efficiency and durability.
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£37.99
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At a Glance
High-quality 0.6mm 316L stainless steel construction
Increases the flue diameter by 25mm for a secure, seamless connection
Compliant with Building Regulations Document J and T600 temperature rating
Designed specifically for MI-FLEX 316 and 904 flexible flue liners
Suitable for use with wood (<20% moisture), gas, oil, and smokeless coal
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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:
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“I saved 20% on my purchase compared to other retailers. Exceptional service!” – Jane D.
The Screw-FIX Increaser - Ø 175-200mm is a top-quality accessory expertly designed for use with MI-FLEX 316 and 904 flexible flue liners. This 0.6mm stainless steel adaptor serves as a transitional joint, increasing the diameter by 25mm from a single wall connecting flue system to a flexible flue liner. Compliant with Building Regulations Document J, it's suitable for appliances operating at temperatures up to 600°C (T600 designation), including those using wood with less than 20% moisture, smokeless coal, gas, and oil.
The increaser must be securely fitted within a masonry chimney and is designed to ensure a gas-tight seal, using fire cement, ceramic rope, or high-temperature sealant. Regular maintenance and sweeping by a competent person are advised, particularly for solid fuel appliances.
SKU: 25-175-MR
Technical Specifications
Material
316L Stainless Steel
Diameter Increase
25mm
Size
u00d8 175-200mm
Temperature Rating
Up to 600u00b0C (T600)
Compatible Systems
MI-FLEX 316 and 904 flexible flue liners
Compliance
Building Regulations Document J
Fuel Compatibility
Wood (<20% moisture), Oil, Gas, Smokeless Coal
The Screw-FIX Increaser must be installed within a masonry chimney to meet regulatory requirements. Begin by ensuring that your flue system is thoroughly inspected and cleaned by a competent person. When fitting the increaser, secure it firmly using a recommended high-temperature sealing method such as fire cement, ceramic rope, or high-temperature sealant. Ensure all connections are gas-tight, and avoid using non-masonry enclosures such as timber or plasterboard. Follow the manufacturer’s guidelines closely and arrange for regular maintenance to sustain optimal performance.
The Screw-FIX Increaser is specifically designed for use with MI-FLEX 316 and 904 flexible flue liners.
The Screw-FIX Increaser is suitable for use with wood (less than 20% moisture), smokeless coal, gas, and oil.
Yes, it complies with the Building Regulations Document J, requiring the increaser to be installed within a masonry chimney.
The Screw-FIX Increaser can handle temperatures up to 600°C (T600 designation).
The connection should be secured using fire cement, ceramic rope, or high-temperature sealant to ensure a gas-tight seal.
No, the increaser must be enclosed within a masonry chimney. Non-masonry enclosures like timber or plasterboard are not acceptable.
The flue system should be inspected and cleaned yearly, but for solid fuel appliances, sweeping twice a year is recommended.
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.
Comprehensive Buyer’s Guide for the Screw-FIX Increaser - Ø 175-200mm
When it comes to maintaining a top-quality heating system, every component must not only perform its function but also integrate seamlessly with other parts of the flue system. The Screw-FIX Increaser - Ø 175-200mm is designed to do just that. This guide will walk you through all the details about this essential product, helping you understand its importance, benefits, and how to integrate it effectively into your flue system setup.
Understanding the Role of the Screw-FIX Increaser
The primary function of this increaser is to serve as a transitional joint between a rigid single wall flue system and a flexible flue liner. By increasing the flue diameter by 25mm, the accessory ensures that different parts of your heating system fit together securely. This is crucial for ensuring that the flue works efficiently and safely. It is specifically tailored for use with MI-FLEX 316 and 904 flexible flue liners, meaning it is engineered to meet the exacting standards required for such systems.
Key Benefits and Features
Durability and Safety: Constructed from 0.6mm 316L stainless steel, this increaser can withstand high temperatures of up to 600°C (T600 designation) and heavy usage over time. The robust material contributes to long-lasting performance, assuring you that the product will endure the demands of regular use.
Compliance with Regulations: This product meets the Building Regulations Document J, which is essential for any installation in a masonry chimney. This compliance guarantees that your installation adheres to all required safety and performance standards.
Versatility in Fuel Types: Whether your heating system uses wood (with a moisture content less than 20%), oil, gas, or smokeless coal, the Screw-FIX Increaser is the ideal accessory. Its design accommodates various fuel sources without compromising on efficiency or safety.
Enhanced System Efficiency: The 25mm diameter increase facilitates a smooth transition between system components, ensuring a gas-tight connection and reducing the risk of sealant or cement failures. This also improves the overall thermal efficiency of the flue system, maintaining optimal heat retention and preventing energy losses.
Installation and Maintenance Guidance
Proper installation is paramount. The increaser must be fitted within a masonry chimney, and it is essential that the joint is sealed properly using fire cement, ceramic rope, or high-temperature sealant. Improper installation may compromise the safety and effectiveness of your heating installation. Regular maintenance is advised, with annual inspections by a competent person, and for solid fuel appliances, sweeping twice a year is recommended to ensure that the system remains in top condition.
Addressing Common Objections
Concern: 'Is it compatible with my existing system?'
Absolutely. The Screw-FIX Increaser is engineered specifically for use with MI-FLEX 316 and 904 flexible flue liners. If your system includes these components, this increaser is guaranteed to provide the perfect fit and function.
Concern: 'What about safety and longevity?'
Constructed from high-quality 316L stainless steel, the increaser not only resists corrosion but is designed to handle substantial temperatures and prolonged use. Its compliance with Building Regulations Document J further underscores its safety credentials.
Concern: 'Will it work with different fuel types?'
Yes, this product is versatile enough to handle a range of fuels, including wood with less than 20% moisture, gas, oil, and smokeless coal, making it a flexible choice for various heating solutions.
Concern: 'How do I ensure a proper seal?'
The key to long-term efficient performance is a gas-tight seal. Make sure you use suitable sealing agents like fire cement, ceramic rope, or high-temperature sealant and follow all installation instructions meticulously.
Making the Right Purchase Decision
When selecting accessories for your flue system, it is essential to consider both the immediate and long-term benefits. The Screw-FIX Increaser - Ø 175-200mm provides peace of mind with its durability, safety compliance, and ease of integration with your MI-FLEX system. It may also serve as a foundation for further enhancements; explore complementary accessories (such as sealing kits, additional support brackets, and maintenance tools) that can bolster your overall setup. Investing in quality components now can lead to fewer maintenance issues and better performance over time.
Final Thoughts
Upgrading or maintaining a flue system is a decision that impacts the safety, efficiency, and overall performance of your heating environment. With the Screw-FIX Increaser, you acquire a product that not only meets industry standards but also offers enhanced reliability through its robust construction and precision engineering. Its compatibility with multiple fuel types and compliance with strict safety regulations ensures that you are making a sound investment. Moreover, by pairing this component with the correct accessories, you can achieve an optimised, efficient flue system that stands the test of time.
When all factors, including durability, safety, and ease of installation, come together, the Screw-FIX Increaser proves itself to be a critical asset in your flue system setup. It offers a clear solution to the transitional challenges faced by installers and homeowners alike. With its proven track record and adherence to the highest standards, you are not just buying a product but investing in long-term performance and safety.
Enhance your heating system today with the reliability and precision of the Screw-FIX Increaser - a product that epitomises quality and efficiency. Buy now or call 01670 206 999.
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