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Increaser 3 diameters - Ø 250 (3-250-202)

The Increaser 3 Diameters Ø 250 by National Flues is the ultimate flue adapter designed for modern heating and ventilation applications. Made from premium 316L stainless steel, this increaser is ideal for both condensing and non-condensing systems. With its CE marking and compliance with EN 1856-1, customers can trust its safety and performance. Whether you are upgrading your boiler or enhancing your chimney shaft liner, this product integrates seamlessly into your flue system, offering flexibility and durability. Explore our optional accessories for a tailored installation experience.
£335.99
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

    Constructed from high-grade 316L stainless steel for durability and corrosion resistance
    CE marked and compliant with EN 1856-1 for trusted safety performance
    Versatile design suitable for both condensing and non-condensing applications
    Simple push-fit jointing system secured with a locking band for quick and secure installation
    Designed for flue systems including boilers, ovens, ventilation systems and chimney shaft liners
    Requires 50mm clearance from combustibles to ensure safe operation

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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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.
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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.

Free Delivery Over £100: Orders over £100 are free delivery (call us if delivery is required outside the mainland UK).

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Have Questions?
Phone: 01670 206999
Email: [email protected]

The Increaser 3 Diameters Ø 250 from the SWPro range is a versatile solution for your flue system needs. Whether you're dealing with high or low temperatures, this increaser is suitable for both condensing and non-condensing applications. Made of durable 316L grade stainless steel, it ensures longevity and reliability.

The SWPro system includes a high-pressure sealing gasket P1/H1, which guarantees a secure and tight fit. It's perfect for a wide range of applications, including boilers, ovens, ventilation systems, and chimney shaft liners. The product has been tested and certified with CE marking under EN 1856-1, assuring its quality and compliance.

Modular in design, the SWPro system features a simple push-fit jointing mechanism secured by a locking band, ensuring ease of installation. For added safety, a 50mm gap from combustible materials such as wood or plasterboard is required.

SKU: 3-250-202

Technical Specifications
SKU3-250-202
Material316L Stainless Steel
CertificationCE Marked (EN 1856-1)
SystemSWPro
Fuel CompatibilityGas, Oil
Warranty10 Years
Safety Clearance50mm from combustible materials
Before installing the Increaser 3 Diameters Ø 250, ensure that all push-fit joints are securely fitted with the designated high-pressure sealing gasket (P1/H1). This product requires careful handling to maintain the integrity of the flue system. Always observe the minimum safety clearance of 50mm from any combustible surfaces such as wood or plasterboard. It is advisable to check compatibility with your existing system and, if needed, consult with a certified professional to ensure compliance with all safety standards. Additionally, consider exploring compatible accessories like locking bands and optional sealing kits to enhance the overall installation process.

The Increaser 3 Diameters Ø 250 is constructed from high-grade 316L stainless steel, ensuring superior durability and resistance to corrosion.

Yes, the Increaser 3 Diameters Ø 250 is designed for both positive and negative pressure flue gas applications.

It is suitable for a wide range of applications including boilers, ovens, ventilation systems, and chimney shaft liners.

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

The increaser features a push-fit jointing system secured with a locking band. Jointing gaskets must be fitted on every joint in P1 and H1 installations.

Ensure a safety distance of 50mm from the outside of the flue to any combustible material like wood or plasterboard.

Yes, it is suitable for both condensing and non-condensing applications.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Tuesday, May 20th. 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 Increaser 3 diameters - Ø 250 buyers guide

Order your Increaser 3 Diameters Ø 250 today to secure a reliable, efficient flue solution for your project.

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