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Screw-FIX Long Tail Increaser - Ø 175-200mm (25-175-MRLT)
National Flues presents the Screw-FIX Long Tail Increaser - Ø 175-200mm, a high-quality stainless steel accessory designed to ensure a seamless transition between rigid and flexible flue systems. Perfect for MI-FLEX installations, our increaser offers durability, efficiency, and compliance with strict building regulations. Whether you are upgrading your chimney system for wood, gas, oil, or smokeless coal appliances, this premium accessory guarantees reliable performance and safety.
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£59.49
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At a Glance
Premium 0.6mm 316-grade stainless steel construction
Designed for MI-FLEX 316 and 904 flexible flue liners
Provides a seamless 25mm transition between rigid and flexible flue systems
Complies with Building Regulations Document J for masonry chimney installations
Suitable for wood (moisture <20%), smokeless coal, gas and oil appliances
Withstands temperatures up to 600°C (T600 designation)
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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:
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 Long Tail Increaser - Ø 175-200mm is a premium accessory in our MI-FLEX range, expertly designed for seamless integration with both MI-FLEX 316 and 904 flexible flue liners. Crafted from 0.6mm 316-grade stainless steel, this durable adaptor ensures a smooth transition from rigid single-wall connecting flue systems to flexible flue liners, offering a 25mm increase. Compliant with Building Regulations Document J, this increaser must be installed within a masonry chimney.
Suitable for use with wood (moisture <20%), smokeless coal, gas, and oil appliances, it withstands temperatures up to 600°C (T600 designation). For a secure and gas-tight installation, it is advisable to use fire cement, ceramic rope or tape, or high-temperature sealant. Regular maintenance, including annual sweeping by a competent person, is essential to ensure optimal performance and safety.
Avoid using chemical cleaners or mild steel tools to prevent damage.
SKU: 25-175-MRLT
Technical Specifications
Product Name
Screw-FIX Long Tail Increaser - u00d8 175-200mm
Material
0.6mm 316-grade stainless steel
Compatible Systems
MI-FLEX 316 and 904 flexible flue liners
Transition Increase
25mm
Operating Temperature
Up to 600u00b0C (T600 designation)
Compliance
Building Regulations Document J, CE / HETAS
Fuel Compatibility
Wood (<20% moisture), smokeless coal, gas, oil
Installation Requirement
Must be installed within a masonry chimney
Recommended Sealants
Fire cement, ceramic rope or tape, high-temperature sealant
Before installation, ensure that your masonry chimney is fully compliant with Building Regulations Document J. The Screw-FIX Long Tail Increaser should be installed as a transitional joint between the rigid single-wall flue system and the flexible MI-FLEX liner. Use approved sealants such as fire cement, ceramic rope or tape, or high-temperature sealant to achieve a gas-tight connection. Regular maintenance—including annual sweeping by a competent person—is essential to ensure the longevity of your flue system. Avoid using chemical cleaners or mild steel tools to prevent damage to the stainless steel.
The increaser is made from high-quality 0.6mm 316 stainless steel, ensuring durability and reliable performance.
Yes, it complies with Building Regulations Document J, which mandates that flexible flue liners be installed entirely within a masonry chimney.
The Screw-FIX Long Tail Increaser is suitable for use with wood (moisture content <20%), smokeless coal, gas, and oil appliances.
The increaser can withstand temperatures up to 600°C (T600 designation).
To ensure a gas-tight seal, use fire cement, ceramic rope or tape, or high-temperature sealant where the increaser connects to both the flexible and rigid flue systems.
The chimney system should be inspected and maintained at least once a year. For solid fuel appliances, sweeping twice a year is recommended.
No, chemical cleaners or mild steel tools should not be used as they can damage the stainless steel components. Instead, use appropriate sweeping tools and methods.
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 Long Tail Increaser - Ø 175-200mm buyers guide
Comprehensive Buyers Guide for the Screw-FIX Long Tail Increaser - Ø 175-200mm
When planning an upgrade or repair for your chimney system, choosing the right transitional accessory is critical. The Screw-FIX Long Tail Increaser from National Flues has been engineered for precision, durability, and ease of use, ensuring that your flue installation is as safe as it is efficient.
What is the Screw-FIX Long Tail Increaser?
The Screw-FIX Long Tail Increaser is a sophisticated adapter designed to seamlessly bridge the gap between your rigid single-wall flue system and MI-FLEX flexible flue liners. Manufactured from 0.6mm 316-grade stainless steel, this long tail adaptor offers a 25mm increase, ensuring a secure, gas-tight transition. Its robust construction is ideal for high-temperature environments, making it suitable for a range of fuels including wood (with less than 20% moisture), smokeless coal, gas and oil appliances.
Key Features and Benefits
Durability and Resilience:
- Crafted from high-quality 316-grade stainless steel, the increaser withstands the rigour of extreme operating temperatures (up to 600°C) and adverse weather conditions, ensuring long-term reliability.
Safety and Compliance:
- Fully compliant with Building Regulations Document J and approved under CE / HETAS, this product meets stringent safety standards, giving you peace of mind that your installation is both safe and legally compliant.
Effortless Integration:
- Specially designed for use with MI-FLEX systems, the increaser offers a straightforward installation process, reducing the chance of installation errors and ensuring that your flue system operates at peak efficiency.
Installation Guidelines and Tips
Proper installation is key to the performance of your flue system. The Screw-FIX Long Tail Increaser should be installed within a masonry chimney. For optimum safety and efficiency, use only approved sealing methods such as fire cement, ceramic rope or tape, or a high-temperature sealant. These products help achieve a gas-tight seal between the solid rigid flue and the flexible liner, preventing any lateral movement or leakage. It is also strongly recommended that your chimney be inspected and swept at least once a year by a competent person.
Addressing Common Objections
**Objection: 'Is it compatible with my current setup?'
- The Screw-FIX Long Tail Increaser is specifically engineered for MI-FLEX systems and works seamlessly with both MI-FLEX 316 and 904 flexible flue liners, ensuring compatibility with a wide range of heating appliances.
**Objection: 'Will it handle extreme temperatures?'
- Absolutely. With a temperature tolerance of up to 600°C, this increaser is designed to perform reliably under the highest operating conditions, making it suitable for both residential and commercial applications.
**Objection: 'I’m concerned about long-term maintenance and safety.'
- The product’s compliance with Building Regulations Document J and its robust construction ensure that it remains safe and efficient with minimal maintenance. Regular inspections and professional sweeping—ideally annually—will keep your flue system in optimal condition.
Why Choose National Flues?
National Flues has long been a trusted name in the chimney and flue market. With our focus on quality, safety, and customer satisfaction, we offer products that not only meet but exceed industry standards. Our Screw-FIX Long Tail Increaser is a testament to our commitment to innovation and performance, providing you with a product that is both technically advanced and easy to install. Our extensive range of MI-FLEX accessories means you can source everything you need from a single, reliable supplier.
Additional Tips for a Successful Installation
- Always verify that all components are compatible before beginning any installation work.
- Ensure that the masonry chimney is structurally sound and compliant with current building regulations.
- Use recommended sealants and follow the manufacturer’s guidelines to guarantee a secure, gas-tight connection.
- Consider professional installation if you are unsure about any aspect of the process. This not only ensures safety but also maximises the efficiency of your flue system.
Final Thoughts
Upgrading your flue system is an investment in safety, efficiency, and comfort. The Screw-FIX Long Tail Increaser - Ø 175-200mm provides a robust solution for bridging the gap between rigid and flexible flue systems. With its high-grade construction, adherence to building regulations, and ease of installation, it represents a top choice for both homeowners and trade professionals alike. National Flues is dedicated to providing products that streamline your installation process and enhance the overall performance of your chimney system. For an installation that is safe, compliant, and built to last, this increaser is an essential component.
Explore our range of MI-FLEX accessories to complement your purchase and ensure every aspect of your flue system is optimised for performance and longevity. Choose confidence, safety, and efficiency with National Flues. Buy now or call 01670 206 999.
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