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DM36 - 360mm square x 250mm high access casing (59-130712)
National Flues proudly presents the DM36 360mm square x 250mm high access casing, a premium chimney accessory engineered for optimal flue gas heat retention and efficiency. This top-quality, double-wall access casing, crafted from natural pumice, is ideal for stoves, open fires, and cookers, offering excellent thermal performance while minimising heat loss. With HETAS approval and CE marking, our DM36 access casing represents the pinnacle of UK chimney technology and is a reliable solution for maintaining a warm, efficient home environment.
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£57.49
Give us a call if you find it cheaper and we'll try to price match.
At a Glance
Constructed from natural pumice for superior insulation
Double-wall design reduces thermal stress and prevents leaks
HETAS approved and CE marked for industry-leading safety standards
Versatile design suitable for stoves, open fires, and cookers (wood, oil, solid fuel, gas)
Features a 150mm internal diameter access hole for easy inspection and maintenance
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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.
Bulk Purchasing Power: We sell a lot, so we can negotiate better rates with suppliers, passing the savings directly to you.
Operational Efficiency: We have streamlined processes to reduce overhead.
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).
“I saved 20% on my purchase compared to other retailers. Exceptional service!” – Jane D.
The DM36 360mm square x 250mm high access casing is part of the Isokern Double Module (DM) block system, renowned for its exceptional thermal insulation and durability. Constructed from natural pumice, this casing maintains optimal flue gas temperatures while preventing heat transference to the outer casing. The unique double-wall structure allows for thermal movement, minimising the risk of cracks and leaks.
Quick and easy to install, the DM36 is suitable for a wide range of heating appliances including stoves, open fires, and cookers using wood, solid fuel, oil, or gas (excluding condensing appliances like Biomass and Pellets). Approved by HETAS and CE marked, the Isokern DM system ensures superior performance and safety, keeping your chimney warmer for longer and reducing condensation and soot build-up.
• Ensure correct clearance from combustibles (0mm on straights; 38mm on offsets with DM System)
• Follow the installation guides provided by National Flues for safe and efficient setup
• Pre-inspect the chimney structure and consult a professional installer if necessary
• Use proper tools and adhere to manufacturer recommendations for mounting and sealing
• Always observe safety warnings and maintenance guidelines to prolong the life of the casing
The DM36 is suitable for use with stoves, open fires, and cookers burning wood, solid fuel, oil, or gas. It is not suitable for condensing appliances, including Biomass and Pellets.
Pumice is a natural insulator, which helps flue gases reach their optimum temperature quickly and maintain it longer. This enhances the heating appliance’s performance and reduces the likelihood of condensation and soot build-up.
Yes, the Isokern DM36 is HETAS Approved and CE marked, ensuring it meets high safety and performance standards.
Yes, the DM36 is suitable for use with gas appliances, provided they are not condensing types like Biomass and Pellets.
The DM36’s double-wall design allows for thermal movement, which reduces the risk of cracking, a common cause of leaks in chimneys.
The DM casing is available in three sizes: DM36, DM44, and DM54.
Installation instructions for the DM36 can be found in the product guides and documentation provided by National Flues.
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 DM36 - 360mm square x 250mm high access casing buyers guide
Introduction
When it comes to maintaining a safe and efficient chimney system, the DM36 access casing from National Flues is an exceptional choice. With its robust design and innovative construction, this product ensures that flue gas temperatures remain at optimum levels, which is critical for the performance and longevity of your heating appliance. In this buyers guide, we will explore all the important features, benefits, installation tips, and frequently asked questions related to the DM36 access casing.
Product Overview
The DM36 is a 360mm square by 250mm high access casing built as part of the renowned Isokern DM block system. Its double-wall design, crafted from natural pumice, not only provides excellent insulation but also supports thermal movement, significantly reducing the risk of cracks and leaks. This design is particularly beneficial for a range of heating appliances including stoves, open fires, and cookers that run on wood, oil, solid fuel, or gas (excluding condensing appliances such as biomass and pellets).
Key Features:
• High-quality natural pumice construction that enhances thermal performance
• Double-wall structure to accommodate thermal movement and ensure longevity
• 150mm internal diameter access hole for easy checks and maintenance
• Certified safety standards with HETAS approval and CE marking
• Suitable for a wide variety of fuel types, making it incredibly versatile
Benefits of the DM36 Access Casing
One of the major advantages of the DM36 access casing is its ability to maintain optimal flue gas temperatures by minimising heat transference to the outer casing. This means that your chimney remains warmer for longer periods, reducing the chance of condensation and the build-up of soot, which in turn preserves the efficiency of your heating appliance. Moreover, its robust construction from natural pumice not only improves insulation but also adds to the overall durability of the structure.
In addition, the DM36 is designed for quick and easy installation, saving you both time and labour costs. This ease of use, combined with its proven safety certifications, makes the DM36 a preferred choice for both residential and trade customers across the UK.
Installation Guidelines
Proper installation is critical to ensuring the long-term performance of your DM36 access casing. Start by carefully reviewing the installation guidelines provided by National Flues. These instructions detail essential steps such as:
- Verifying clearance requirements (0mm on straights and 38mm on offsets when used with the DM System)
- Ensuring all fittings are securely attached and sealed to prevent any leaks or heat loss
- Consulting a professional installer if there is any uncertainty about proper installation procedures
Following these steps will not only safeguard your investment but also maximise the performance benefits of your access casing.
Frequently Asked Questions
What fuels is the DM36 access casing compatible with?
The DM36 is suitable for use with stoves, open fires, and cookers that operate on wood, oil, solid fuel, or gas. However, it is not recommended for condensing appliances such as those using biomass or pellets.
How does the double-wall design benefit my chimney setup?
The double-wall design allows for optimal thermal movement. This significantly reduces the risk of cracking and leaking, ensuring a longer lifespan for your installation and better maintenance of flue gas temperatures.
Can I install the DM36 myself?
While the DM36 is designed for quick and easy installation, we always recommend consulting the provided guidelines and considering professional assistance, especially if you are uncertain about any step in the process.
Why Choose National Flues?
At National Flues, we are dedicated to offering products that combine quality, safety, and efficiency. Our DM36 access casing is a testament to our commitment to excellence. With readily available nationwide delivery and a user-friendly online ordering system, supporting your chimney system’s performance has never been easier. We understand that investing in a high-quality component for your heating appliance is crucial, and we stand by our product with a 10-year warranty to ensure your peace of mind.
Final Considerations
Choosing the right access casing is pivotal for maintaining the performance and safety of your heating appliance. The DM36 access casing not only meets but exceeds industry standards by offering a durable, efficient, and versatile solution that keeps your chimney system operating at its best. With features that are designed to tackle common issues such as thermal stress and condensation, the DM36 represents an investment in long-term reliability and superior heating performance.
If you have any further questions or need additional insights on installation and maintenance, our customer service team is always available to help. We invite you to explore all the benefits of this premium product and see how it seamlessly integrates into your home’s heating system.
Add the DM36 access casing to your cart today, or get in touch with our experts for personalized advice. buy now or call 01670 206 999.
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