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Pack 504 - (125mm, P/C/PS/N/CNP/20-100-MR) (20-125-P504)

The National Flues Pack 504 is a premier 125mm flue installation kit that offers a reliable, compliant, and efficient solution for chimney flue liner installations. Ideal for both professional installers and DIY enthusiasts, this top-of-the-range kit provides all necessary installation accessories, ensuring a smooth and trouble-free setup while maintaining full regulatory compliance. Read more...
Pack 504 - (125mm, P/C/PS/N/CNP/20-100-MR)
IN STOCK
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Now only £48.99
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At a Glance

  • All-inclusive installation kit for 125mm MI-FLEX flue liners
  • Meets Building Regulations Document J requirements
  • Constructed from robust 316L stainless steel
  • Compatible with multiple fuel types (wood, smokeless coal, gas, oil)
  • Includes top plate, top clamp, nose cone, increasing adaptor and chimney notice plate

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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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Price Match Guarantee: If you find the same product cheaper within 48 hours, we’ll match it and refund the difference.

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

The Pack 504 - (125mm, P/C/PS/N/CNP/20-100-MR) is an all-inclusive installation kit designed for MI-FLEX 316 and 904 flexible flue liners. Perfectly suited for creating a comprehensive chimney system, this kit allows you to replace an existing chimney pot and install a new flue liner with ease. This pack includes a 125mm Top Plate, Top Clamp, Nose Cone, and an Increasing Adaptor to Black Pipe or Single Wall Flue with dimensions from 100mm SW to 125mm Flex.

Additionally, a Chimney Notice Plate is provided. Building Regulations Document J stipulates that flexible flue liners must be fully enclosed within a masonry chimney, and this kit meets all necessary requirements. Suitable for appliances up to 600°C and compatible with wood (under 20% moisture), smokeless coal, gas, and oil, it ensures a robust and durable installation.

SKU: 20-125-P504

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
SKU20-125-P504
Product NamePack 504 - (125mm, P/C/PS/N/CNP/20-100-MR)
Material316L Stainless Steel
Dimensions125mm Top Plate; Increasing adaptor fits 100mm SW to 125mm Flex
FinishNatural / Stainless Steel
ApprovalsHETAS, CE
Compatible FuelsWood (<20% moisture), Smokeless Coal, Gas, Oil
SystemMI-FLEX Accessories MF20
Before installation, ensure that the entire chimney flue liner is fully enclosed within a masonry structure as mandated by Building Regulations Document J. The Pack 504 is designed to replace an existing chimney pot and includes all components required for a complete installation. Begin by carefully removing the old chimney pot and cleaning the working area. Install the 125mm top plate and secure it firmly using the provided top clamp. Next, position the nose cone to ensure a neat finish and effective protection against weather exposure. Attach the increasing adaptor to transition from a 100mm Single Wall Flue (SW) to a 125mm MI-FLEX flue liner, ensuring a snug and secure fit. Finally, fix the chimney notice plate in a visible location to display essential safety and maintenance information. Note: This kit is not recommended for use in timber or plasterboard enclosures. Always consult a qualified professional if unsure about any aspect of the installation. Regular maintenance and annual inspections are strongly advised to keep your chimney system functioning safely.

The kit includes a 125mm Top Plate, Top Clamp, Nose Cone, Increasing Adaptor to Black Pipe or Single Wall Flue (100mm SW to 125mm Flex), and a Chimney Notice Plate.

Yes, this kit is suitable for wood (under 20% moisture), smokeless coal, gas, and oil appliances up to 600°C.

No, Building Regulations Document J requires that a flexible flue liner must be installed completely enclosed inside a masonry chimney.

While the MI-FLEX liner itself is not included, this kit provides all necessary accessories for installation. You may also need a cowl or terminal for weather and bird protection.

Cleaning and inspection should be carried out at least once a year. For solid fuel appliances, it is recommended to sweep the chimney at least twice a year.

Avoid using chemical cleaners or mild steel tools on stainless steel chimneys. It is best to use a professional sweep listed on HETAS.

The Chimney Notice Plate provides important information about the chimney system, including its design and maintenance requirements, ensuring safety and compliance.

 

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