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Increasing MI-FLEX Adaptor - Ø 125-Ø 150 (20-125-MR)

National Flues presents the Increasing MI-FLEX Adaptor – Ø 125-Ø 150, a leading choice for those seeking durable and efficient MI-FLEX accessories. This high-quality 316L stainless steel adaptor provides a seamless and reliable transition between your single wall flue and MI-FLEX flue liner, ensuring a fully compliant installation that enhances both performance and safety.

What it’s for

The Increasing MI-FLEX Adaptor - Ø 125-Ø 150 serves as a crucial component for connecting a single wall flue system to MI-FLEX flexible flue liners, ensuring a stable and compliant transition within masonry chimneys.

Full features & benefits

  • ✓
    Constructed from 316L stainless steel ensuring longevity and resistance to corrosion, providing peace of mind over years of service
  • ✓
    0.6mm thickness offers superior structural integrity, safeguarding your chimney system against high temperatures
  • ✓
    With a T600 rating, the adaptor performs reliably in extreme heat conditions, making it ideal for various fuel appliances
  • ✓
    Seamlessly bridges the gap between single wall flues and MI-FLEX liners, ensuring optimal performance and safety
  • ✓
    Adheres to Building Regulations Document J, guaranteeing a compliant and secure installation
  • ✓
    Suitable for varied fuel types, offering flexibility and efficiency for different heating systems
Increasing MI-FLEX Adaptor - Ø 125-Ø 150
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At a Glance

  • Premium 316L stainless steel construction
  • Robust 0.6mm thickness for enhanced durability
  • Heat resistance rated up to 600°C (T600)
  • Seamless connection between single wall flue and MI-FLEX liner
  • Compliant with Building Regulations Document J
  • Versatile for wood, oil, gas, and smokeless coal appliances

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.

Have Questions?
Phone: 01670 206999
Email: sales@nationalflues.com

The Increasing MI-FLEX Adaptor - Ø 125-Ø 150 is a high-quality 0.6mm 316 stainless steel accessory designed for seamless transition and connection between a single wall connecting flue system and an MI-FLEX flexible flue liner. Constructed to withstand temperatures up to 600°C (T600 designation), it is suitable for use with wood (less than 20% moisture), smokeless coal, gas, and oil appliances. This adaptor is essential for forming a complete chimney system in compliance with Building Regulations Document J, requiring a fully enclosed masonry chimney.

Do not use non-masonry enclosures like timber or plasterboard. Ensuring a gas-tight seal at the bottom fixing, the connection should be secured within the masonry chimney, utilizing fire cement, ceramic rope or tape, or high-temperature sealant. Regular sweeping and maintenance by a competent person are vital, especially for solid fuel appliances.

Use only appropriate cleaning tools, avoiding chemical cleaners and mild steel tools. Recommended sweeping twice a year ensures the longevity and safety of your chimney system.

SKU: 20-125-MR

Delivery Information* +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, November 14th. This is based on current lead times. Bear in mind that it is a busy time of year. If you need a product delivered by a specific time in the next 7 days, then please give us a call on 01670 206 999. Visit our Shipping Information page for more information.

About National Flues Ltd +

We began over 30 years ago as a fireplace shop in the North East. We now supply hundreds of trade professionals and thousands of retail customers, all across the UK, every month. We are still a family owned business, lead by the MD Neil, and always try our best to deliver the best possible experience. We also price match, so give us a call if you find this cheaper and want to buy from us. Visit our about us page to read a bit more.

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Technical Specifications
Model20-125-MR
Material316L Stainless Steel
Thickness0.6mm
Heat RatingT600 (Up to 600°C)
FinishNatural / Stainless Steel
Compatible FuelsWood (with less than 20% moisture), Oil, Gas, Smokeless Coal
CertificationsHETAS / CE
SystemMI-FLEX Accessories MF20
Installation MethodSecured within a masonry chimney using fire cement, ceramic rope or tape, or high-temperature sealant
For a compliant and secure installation, fit the Increasing MI-FLEX Adaptor inside your masonry chimney. Secure the connection at the bottom using fire cement, ceramic rope or tape, or a high-temperature sealant to create a gas-tight seal. Ensure the adaptor is installed by a qualified professional following local building regulations. Regular chimney sweeping by a competent person is recommended—twice annually for solid fuel appliances and once a year for gas or oil—to maintain optimum performance and safety. Avoid using chemical cleaners or mild steel tools when performing maintenance on stainless steel components.

The adaptor is constructed from 0.6mm thickness 316 stainless steel, known for its durability and heat resistance.

It is suitable for use with appliances burning wood (with less than 20% moisture content), smokeless coal, gas, and oil, handling temperatures up to 600°C.

Yes, it complies with Building Regulations Document J which mandates that flexible flue liners must be enclosed within a masonry chimney.

The adaptor should be used inside a masonry chimney, secured using fire cement, ceramic rope or tape, or high-temperature sealant to create a gas-tight seal.

For chimneys serving solid fuel appliances, sweeping is recommended twice annually - post-heating season and pre-next heating season. Gas and oil lines should be inspected and cleaned at least once a year.

Avoid chemical cleaners and mild steel tools on stainless steel chimneys. Use appropriate brushes and tools to protect the integrity of the system.

For solid fuel applications, HETAS registered sweeps can be found at hetas.co.uk. Ensure sweeping and maintenance are carried out by competent persons.

 

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