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Lid with drain - Ø 400 (3-400-037)

Discover the high-grade Lid with Drain - Ø 400 from National Flues, a premium flue component ideal for commercial and domestic settings. This robust flue cap, crafted from 316L stainless steel and incorporating a secure push-fit assembly, is an essential part of the SWPro modular single wall flue system. Perfect for applications in boilers, ovens, and ventilation, this product offers reliable drainage with its integrated BSP connection. Enhance your installation with optional accessories such as Read more...
The price you pay today £223.99
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At a Glance

    Constructed in high-grade 316L stainless steel
    Designed for SWPro modular single wall flue systems
    Engineered for both high and low-temperature applications
    Integrated drainage system with BSP stainless steel connection
    Equipped with a secure push-fit jointing system and sealing gaskets for enhanced safety
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, June 27th. This is based on current delivery times for this product. Delivery for products not in our warehouses can be delayed because of third party carriers. If you need a stove, or other bulky product, to be delivered by a specific time in the next 7 days then please 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 and you can read in our blog about they types and terms and conditions for warranties. Mi-Flex flue liner, for example, comes with a lifetime guarantee. Give us a call if you want to know about a specific warranty. Returns for damaged items are covered by insurance; non-damaged returns incur return delivery costs.

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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.

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:

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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 Lid with drain - Ø 400 is an essential component in the SWPro modular single wall flue system, crafted from high-grade 316L stainless steel. It is designed for a variety of high and low-temperature applications, including boilers, ovens, and ventilation systems. This cap end with a drain is typically positioned at the bottom of a vertical run, often under a tee, to facilitate drainage.

The product includes a BSP stainless steel connection for easy attachment to drainage pipework. Our SWPro system incorporates a high-pressure sealing gasket, making it suitable for both non-condensing and condensing applications with positive or negative pressure flue gasses. The system offers CE-marked approval under the standard EN 1856-1 and features an efficient push fit jointing system, secured with a locking band.

For P1 and H1 installations, jointing gaskets are mandatory for added safety. Ensure a 50mm clearance from any combustible materials during installation.

SKU: 3-400-037

Technical Specifications
SKU3-400-037
Material316L Stainless Steel
SystemSWPro Modular Single Wall Flue
ConnectionsBSP Stainless Steel Drain Connection
ApplicationsBoilers, Ovens, Ventilation Systems, Chimney Shaft Liners
SealingHigh-pressure sealing gasket with push-fit jointing secured by a locking band
CE ApprovalEN 1856-1 Compliant
ClearanceMinimum 50mm from combustibles
Warranty10 Years
Ensure a minimum clearance of 50mm from any combustible materials during installation. Always use the specified jointing gaskets, especially for P1 and H1 installations, to safeguard the integrity of your flue system. When installing the Lid with Drain - Ø 400, check that all connections are secure, particularly the BSP stainless steel connection for drainage. For best performance, refer to our detailed installation guides and consider pairing the lid with compatible accessories such as additional drainage pipes and enhanced sealing kits, available separately.

The Lid with Drain - Ø 400 is constructed from high-grade 316L stainless steel.

This product is suitable for a wide range of applications, including boilers, ovens, ventilation systems, and as a chimney shaft liner.

The SWPro system uses a high-pressure sealing gasket (P1/H1), making it suitable for both non-condensing and condensing applications with flue gasses in positive and negative pressure.

Yes, the Lid with Drain - Ø 400 and the SWPro flue system are CE marked and comply with EN 1856-1 standards.

During installation, ensure a 50mm distance from any combustible material like wood or plasterboard. For P1 and H1 installations, jointing gaskets must be fitted at every joint.

The push fit jointing system allows for easy assembly by pushing the components together and securing them with a locking band.

Yes, National Flues offers trade accounts, ensuring our trade customers receive competitive pricing and dedicated service.

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