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National Flues presents the Increasing MI-FLEX Adaptor - Ø 100 to Ø 125, a premium accessory engineered for seamless integration between rigid single-wall flue systems and MI-FLEX flexible flue liners. Crafted from high-quality 316L stainless steel, this adaptor ensures a reliable, gas-tight seal required for safe operation. Ideal for use with a wide range of fuels including wood, oil, gas, and smokeless coal, our MI-FLEX Adaptor is designed to perform under rigorous conditions up to 600°C. Trust National Flues for top-tier quality, efficiency, and nationwide delivery service.
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£20.49
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At a Glance
Seamless transition from a single-wall rigid flue to a flexible MI-FLEX liner
Constructed from durable 316L stainless steel for long-lasting performance
Supports a range of fuels including wood (<20% moisture), oil, gas, and smokeless coal
Withstands high operating temperatures up to 600°C (T600 designation)
HETAS and CE approved to meet Building Regulations Document J
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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 Increasing MI-FLEX Adaptor Ø 100 to Ø 125 is a must-have accessory for your MI-FLEX 316 and 904 flexible flue liners. This robust 0.6mm 316 stainless steel adaptor is meticulously crafted to serve as a transitional joint, increasing the diameter from a single-wall connecting flue system to a flexible liner by up to 25mm. Ideal for use with appliances operating at temperatures up to 600°C (T600 designation), it supports wood with less than 20% moisture, smokeless coal, gas, and oil.
Complying with Building Regulations Document J, this adaptor must be used within a fully enclosed masonry chimney. Ensuring a secure, gas-tight seal is critical – fire cement, ceramic rope, tape, or high-temperature sealant is recommended for optimal connection integrity. Regular maintenance is essential, with HETAS registered sweeps recommended for solid fuel applications.
Sweep your chimney at least twice a year for optimal performance and longevity.
SKU: 20-100-MR
Technical Specifications
SKU
20-100-MR
Material
316L Stainless Steel
Adaptor Diameter
u00d8 100 to u00d8 125 mm
Wall Thickness
0.6 mm
Operating Temperature
Up to 600u00b0C
Fuel Compatibility
Wood (<20% moisture), Oil, Gas, Smokeless Coal
Standards
HETAS / CE Approved
System
MI-FLEX Accessories MF20
Before installing the Increasing MI-FLEX Adaptor, ensure your flue system is completely enclosed within a masonry chimney, as stipulated by Building Regulations Document J. Begin by properly preparing the surfaces for a gas-tight seal. Use high-temperature sealants such as fire cement, ceramic rope, or tape to secure joints reliably. Avoid using chemical cleaners or mild steel tools on stainless steel components. It is recommended to have the installation checked by a HETAS registered professional to ensure compliance with all safety standards. Regular maintenance, including bi-annual flue sweeps, is essential for ensuring optimal performance and longevity of the system.
This adaptor is specifically designed for use with MI-FLEX 316 and 904 flexible flue liners, ensuring seamless transitions and secure connections.
The adaptor is suitable for use with wood (<20% moisture), smokeless coal, gas, and oil, and can handle temperatures up to 600°C.
Yes, Building Regulations Document J requires that the flexible flue liner and its accessories must be installed within a fully enclosed masonry chimney.
To ensure a gas-tight seal, use fire cement, ceramic rope or tape, or high-temperature sealant during installation.
Can chemical cleaners be used for chimney maintenance?
No, chemical cleaners and mild steel tools should not be used on stainless steel chimneys. Professional chimney sweeps, preferably registered with HETAS, should be engaged for this task.
The Increasing MI-FLEX Adaptor provides a transitional increase of up to 25mm from the single wall flue to the flexible flue liner.
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.
When planning a chimney installation or upgrade, selecting the right accessories is crucial. The Increasing MI-FLEX Adaptor - Ø 100 to Ø 125 is a vital component for those seeking to connect a rigid single-wall flue with a flexible MI-FLEX liner. In this comprehensive guide, we will explore why this adaptor is a must-have for your flue system, how to install it correctly, and the maintenance required for ensuring long-term performance.
Overview
The Increasing MI-FLEX Adaptor is engineered from durable 316L stainless steel, ensuring resilience against corrosion and high temperatures. It is specifically designed to bridge the gap between a rigid flue system and a flexible liner, accommodating an increase in diameter of up to 25mm. This is essential for achieving a safe, efficient, and compliant chimney system. With industry approvals (HETAS and CE) and compliance with Building Regulations Document J, this adaptor delivers both performance and peace of mind.
Key Benefits
Seamless Integration:
- The design of this adaptor ensures a smooth transition between different sections of your flue, eliminating potential weak points that could compromise the integrity of the system.
Enhanced Durability:
- Constructed from high-grade 316L stainless steel, it is resistant to harsh environmental conditions, meaning you can expect it to stand the test of time even with high operating temperatures up to 600°C.
Versatile Fuel Compatibility:
- Whether you are using wood (with less than 20% moisture), smokeless coal, oil, or gas, this adaptor performs reliably under various fuel conditions, making it a versatile choice for different heating requirements.
Safety and Compliance:
- With HETAS and CE approvals, the adaptor meets stringent safety standards. Its use within a fully enclosed masonry chimney adheres to Building Regulations, ensuring your installation is not only efficient but also legally compliant.
Installation Guidelines
Proper installation is key to maximising the benefits of your Increasing MI-FLEX Adaptor. Always remember that the adaptor must be installed within a fully enclosed masonry chimney to comply with regulatory standards. Follow these critical installation steps:
- Preparation: Clean and inspect all flue components before beginning the installation. Ensure that the surfaces are free from debris to help establish a strong seal.
- Applying Sealant: For a gas-tight seal, apply suitable fire cement, ceramic rope, or high-temperature sealant to all joints where the rigid flue meets the flexible liner.
- Professional Help: Even if you are experienced, it’s advisable to have a professional, preferably a HETAS registered sweeper, inspect the installation post-setup. This guarantees that your new system is safe and efficient.
- Regular Maintenance: Besides installation, regular maintenance is essential. A bi-annual inspection and sweep (especially for solid fuel applications) will help maintain optimum performance and extend the lifespan of your flue system.
Maintenance and Safety
Continued safety and performance of your chimney system depend on regular maintenance. Avoid the use of chemical cleaners or inappropriate tools such as mild steel brushes that may damage stainless steel surfaces. Schedule regular sweeps and inspections to keep your flue system operating safely. If you’re ever in doubt about the condition of your system, consult with a HETAS registered professional to avoid any safety risks.
Solving Common Customer Objections
Some customers often worry about the complexity of installation or potential compatibility issues. However, the Increasing MI-FLEX Adaptor has been engineered with ease of use in mind. Its design simplifies the connection process between rigid and flexible flue systems, reducing both installation time and potential errors.
Objection: Is it Difficult to Install?
- Not at all. With clear installation instructions and the option to consult professionals, the process is straightforward and accessible to experienced DIY enthusiasts as well as professional installers.
Objection: What About Long-Term Durability?
- Made from robust 316L stainless steel, this adaptor is built to last and perform under harsh conditions, ensuring safety and efficiency for many years.
Final Considerations
Before deciding on your chimney accessories, consider the overall performance, longevity, and safety of your flue system. The Increasing MI-FLEX Adaptor offers exceptional quality and meets all necessary regulations and industry standards. Whether you are installing a new chimney system or upgrading an existing one, this adaptor plays a crucial role in ensuring a seamless and efficient connection.
National Flues stands by the quality and performance of our products, ensuring that each component is designed with your safety and operational efficiency in mind. With clear specifications, dependable performance, and comprehensive installation guidelines, this adaptor is a worthy investment for any homeowner or trade professional looking to optimise their chimney system.
Investing in the right accessories not only enhances the performance of your flue but also contributes significantly to the overall safety of your home. For anyone keen on ensuring that their heating system operates at peak efficiency, the Increasing MI-FLEX Adaptor is an indispensable component. It is built to meet the demanding requirements of modern heating systems, combining ease of installation, lasting durability, and regulatory compliance.
Enhance your installation today by choosing a product that guarantees quality, safety, and efficiency. Buy now or call 01670 206 999.
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