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Reducer 2 diameters - Ø 450 (3-350-108)

National Flues presents the Reducer 2 Diameters - Ø 450, a premium flue reducer designed to optimise your commercial flue systems. As a critical component in your installation, this diameter adapter is crafted from 316L stainless steel and engineered to support a wide range of heating applications, including boilers, ovens, and ventilation systems. With robust quality assurance, CE marking, and compliance with EN 1856-1 standards, our product stands out as a reliable choice for both non-condensing and condensing conditions. Enhance your flue system with our state-of-the-art transition solution that delivers efficiency and safety for modern commercial installations.
£662.21
with free delivery Give us a call if you find it cheaper and we'll try to price match.

 

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At a Glance

    Made from high-grade 316L stainless steel for unmatched durability
    Designed for both high and low-temperature environments
    Modular push-fit jointing system with a secure Locking Band
    Equipped with a high-pressure sealing gasket (P1/H1) for safety under varying pressures
    Versatile application across boilers, ovens, ventilation systems, and chimney shaft liners
    Compliant with CE marking and EN 1856-1 standards for reliable performance

Please Note: All dimensions refer to the internal diameter of flues. If unsure, please call 01670 206999 to ensure you choose the correct products.

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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
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The Reducer 2 diameters - Ø 450 is an essential component in the SWPro modular single-wall flue system, expertly crafted from 316 grade stainless steel. This reducer is built to handle both high and low-temperature applications and is compatible with non-condensing and condensing conditions. It features a high-pressure sealing gasket (P1/H1), making it suitable for positive and negative pressure scenarios.

Applications range from boilers and ovens to ventilation systems and chimney shaft liners.Constructed with high-grade 316L Stainless Steel, the wall thickness varies with the flue diameter to ensure durability and efficiency. The SWPro system is CE marked, with credentials including EN 1856-1: T200 H1 W Vm L50040 O(50) - Ø 80 up to Ø 200 and EN 1856-1: T200 H1 W Vm L50050 O(50) - Ø 250 up to Ø 400.Installation is straightforward with its modular push-fit jointing system secured by a Locking Band. For P1 and H1 installations, jointing gaskets are required at each connection point.

Always maintain a distance of 50mm from the outside of the flue to any combustible materials such as wood or plasterboard.

SKU: 3-350-108

Technical Specifications
Model3-350-108
Material316L Stainless Steel
SystemSWPro
DimensionsReducer 2 Diameters - u00d8 450 / u00d8 350
StandardsCE marked, EN 1856-1 compliance
GasketHigh-pressure sealing gasket (P1/H1)
Warranty10 Years
Fuel CompatibilityGas, Oil
Sealing Distance50mm from combustibles
InstallationModular push-fit jointing with Locking Band
Installation Instructions: - Ensure that all components are clean and free of debris before installation. - Fit the reducer securely using the modular push-fit jointing system, and fasten with the Locking Band. - For P1 and H1 installations, install jointing gaskets at every connection point to ensure a tight, secure seal. - Maintain a minimum distance of 50mm from the flue's exterior to any combustible materials such as wood or plasterboard. - Adhere strictly to safety guidelines and local building regulations; consider professional assistance if unsure.

The reducer is made from high-grade 316L stainless steel, ensuring durability and resistance to high temperatures.

Yes, the reducer is built to handle both high and low-temperature scenarios, making it versatile for various applications.

The reducer is ideal for boilers, ovens, ventilation systems, and as a chimney shaft liner.

Yes, the SWPro system is CE marked and complies with EN 1856-1 standards.

The reducer uses a modular push-fit jointing system secured with a Locking Band. For P1 and H1 installations, jointing gaskets are required at every joint.

Ensure a distance of 50mm is maintained from the outside of the flue to any combustible materials like wood and plasterboard.

The reducer is equipped with a high-pressure sealing gasket suitable for both positive and negative pressure applications.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Monday, May 12th. Delivery times of products not in our warehouses depend on product availability and shipping. If you need a definitive delivery time give us a call. If you need faster stove or fireplace delivery please also give us a call. We can sometimes 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 Reducer 2 diameters - Ø 450 buyers guide

Secure superior performance and safety – add this Reducer to your cart now!

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