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IL - Tee Cap - Ø 100 (24-100-32)

Discover the reliability and superior performance of the IL Tee Cap Ø 100, a high-quality chimney flue cap designed for naturally aspirated domestic gas appliances. Engineered in the UK, this indispensable component from the renowned IL gas vent systems offers robust sealing and excellent thermal insulation. Whether you’re upgrading an existing chimney system or installing a new one, this tee cap delivers the quality and safety standards you need. Explore a product that perfectly complements your flue system while ensuring optimal performance and durability.
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£7.99
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At a Glance

  • Premium aluminium liner combined with a durable zalutite outer casing
  • Twin wall insulation with an effective 6mm air gap
  • Specifically designed to cap a 90-degree tee in chimney flue systems
  • Handles flue gas temperatures up to 250°C for reliable performance
  • Suitable for naturally aspirated domestic gas appliances
  • Available in 100mm, 125mm, and 150mm diameters to suit your system
  • Secure push fit and twist lock joint method for easy installation
  • Meets CE and BS EN 9001:2008 standards
  • Backed by a 5 year conditional warranty
  • Trusted performance with over 25 years of UK market experience

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

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.
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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 IL Tee Cap Ø 100 is an essential component of your chimney flue system, designed specifically for naturally aspirated domestic gas-fired appliances fitted with a draught hood or diverter. Built with over 25 years of trusted performance in the UK, this twin wall insulated, pre-fabricated gas vent maintains optimal function under negative pressure and dry conditions, withstanding flue gas temperatures up to 250°C. Available in three diameters (100mm, 125mm, and 150mm), the IL Tee Cap features an aluminium liner paired with a durable zalutite outer casing, separated by a 6mm air gap for enhanced insulation.

While suitable for both internal and external applications, it is not designed for condensing or positive pressure systems.

SKU: 24-100-32

Technical Specifications
Diameter100mm (also available in 125mm and 150mm)
Inner MaterialAluminium
Outer MaterialZalutite (zinc-aluminium coated steel)
Insulation6mm air gap
Max Flue Gas Temperature250u00b0C
Distance To Combustibles50mm (2 inches)
ApprovalsCE, BS EN 9001:2008
Joint MethodPush fit and twist lock
Warranty5 year conditional warranty
Fuel CompatibilityDomestic gas appliances
ApplicationInternal and external (not for condensing or positive pressure systems)
Before installation, ensure your chimney flue system is completely dry and in good condition. The IL Tee Cap Ø 100 is designed to cap a 90-degree tee securely. Begin by measuring your flue system to confirm a 100mm fit, noting that larger diameters (125mm and 150mm) are also available. Follow these steps: 1. Inspect all flue components for any damages. 2. Fit the tee cap onto the 90-degree connection ensuring a snug fit. 3. Secure the cap using the twist lock mechanism to prevent any dislodgement. 4. Verify that a clearance of at least 50mm from any combustible material is maintained. Always adhere to local regulations and, if uncertain, consult a qualified professional to ensure a safe installation. Note: This product is not suitable for condensing or positive pressure systems.

The IL Tee Cap Ø 100 is used to cap a 90-degree tee in chimney flue systems, ensuring proper sealing and functioning for naturally aspirated domestic gas appliances.

Yes, the IL Tee Cap Ø 100 is suitable for both internal and external applications.

No, this product is not suitable for condensing and positive pressure applications.

It features an aluminium liner and a zalutite outer casing separated by a 6mm air gap.

Besides the 100mm diameter, the IL Tee Cap is also available in 125mm and 150mm sizes.

The IL Tee Cap Ø 100 can handle flue gas temperatures up to 250°C.

The IL gas vent system has been trusted and used in the UK for over 25 years.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Wednesday, April 30th. If you need faster stove or fireplace delivery please give us a call. We can often 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 IL - Tee Cap - Ø 100 buyers guide

Don’t wait – upgrade your chimney flue system today with the IL Tee Cap Ø 100.

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