Product Description

904 Stainless Steel Flue Liner Kit 3 – 5 Inch 125mm

Model: 904/904 Flue Liner Kit 3, 5 Inch

The 904 Stainless Steel Flue Liner Kit 3 contains the main parts needed to line a suitable masonry chimney. The kit includes your chosen continuous liner length, a terracotta anti-downdraught pot hanger cowl, a nose cone, a chimney ID plate and an equal vitreous-to-liner adaptor.

The flexible liner has a 125mm (5-inch) internal diameter. Both skins use premium 904L-grade stainless steel. Therefore, this liner provides greater resistance to the harmful deposits that suitable solid-fuel and multifuel appliances can produce.

The anti-downdraught pot hanger supports the liner from a suitable terracotta chimney pot. In addition, its fixed design helps reduce problems caused by wind blowing down the chimney.

This liner can form part of a suitable system for compatible appliances that burn dry wood, approved smokeless coal, coke, gas, oil or cured dry peat. However, your installer must confirm the correct liner diameter, steel grade and fuel before you order.

Important: Some wood-burning installations require a 150mm liner unless the appliance has approval for a 125mm flue. Always check the appliance instructions and current installation rules before choosing this 125mm liner.

Made-to-measure product: We cut the liner to the length you select. Therefore, you cannot return it after we cut or order it. Please check the diameter and required length carefully before completing your purchase.

What Is Included in Flue Liner Kit 3

• Your chosen continuous length of 125mm (5-inch) 904/904 flexible flue liner
• 1 x flue liner nose cone
• 1 x chimney identification plate
• 1 x terracotta anti-downdraught pot hanger cowl
• 1 x 125mm equal vitreous-enamel pipe-to-flue-liner adaptor

We supply the flexible liner as one continuous length. For example, if you order ten metres, you will receive one ten-metre liner. You will not receive ten separate one-metre sections.

904 Flue Liner Kit 3 Key Features

• 125mm (5-inch) internal flue diameter
• Premium 904L stainless-steel inner and outer skins
• Double-skinned flexible construction
• Suitable for relining a compatible masonry chimney
• Smooth inner skin supports the flow of flue gases
• Ribbed outer skin provides flexibility during installation
• Four-fold Quattro-lock seam
• Includes a terracotta anti-downdraught pot hanger cowl
• Helps reduce wind-driven downdraught
• Includes an equal vitreous-to-liner adaptor
• HETAS-listed flexible flue liner
• Classification: EN 1856-2 T450 N1 D V3 L50012 G
• Lifetime manufacturer’s warranty on the liner, subject to conditions
• 10-year manufacturer’s warranty on the kit components, subject to conditions

Why Choose Flue Liner Kit 3

Choose Kit 3 when the installation needs a chimney-pot hanger with added protection against downdraught. The kit brings the main parts together in one package. As a result, you do not need to choose each component separately.

The pot hanger fits onto a suitable terracotta chimney pot. It supports the flexible liner while also forming the chimney terminal. Meanwhile, the anti-downdraught design helps shield the outlet from changing wind directions.

The nose cone helps guide the liner through the chimney. In addition, the equal adaptor connects the liner to compatible 125mm vitreous-enamel stove pipe.

What Is the Difference Between Kit 2 and Kit 3

Kit 2 and Kit 3 contain similar liner and connection parts. However, they use different chimney-pot terminals.

Kit 2 includes a standard terracotta pot hanger cowl. It suits many installations where the chimney does not suffer from wind-related draught problems.

Kit 3 includes a terracotta anti-downdraught pot hanger cowl. Therefore, it may suit exposed properties or chimneys affected by strong winds.

An anti-downdraught cowl cannot correct every chimney problem. Poor draught may result from the chimney height, nearby buildings, trees, blockages or the appliance. Therefore, ask a qualified installer or chimney specialist to check the system.

Why Choose a 904L Flue Liner

A 904/904 liner uses 904L stainless steel for both its inner and outer skins. This premium grade offers greater resistance to corrosion from soot, moisture and harmful flue deposits.

As a result, many customers choose a 904L liner for frequent stove use or suitable multifuel appliances. It can also provide greater peace of mind when the appliance may burn approved smokeless fuels.

A premium liner cannot replace correct installation and care. You must still burn suitable fuel, sweep the chimney and maintain the appliance regularly.

904 Flue Liner Construction

• Inner skin material: 904L-grade stainless steel
• Outer skin material: 904L-grade stainless steel
• Inner skin thickness: 0.105mm
• Outer skin thickness: 0.105mm
• Internal diameter: 125mm
• Imperial diameter: 5 inches
• Construction: double skinned
• Seam type: four-fold Quattro-lock seal
• Classification: EN 1856-2 T450 N1 D V3 L50012 G

The smoother inner skin helps combustion gases travel upwards. Meanwhile, the ribbed outer skin gives the liner enough flexibility to pass through a suitable masonry chimney.

The manufacturer forms the liner from one continuous strip of stainless steel. It then folds the seam across four layers to create a strong Quattro-lock joint.

Suitable Fuels and Appliances

Depending on the appliance and complete chimney design, this 904L liner can suit compatible systems that use:

• Seasoned dry wood
• Approved smokeless coal
• Approved low-sulphur fuel
• Coke
• Cured dry peat
• Oil
• Gas

Do not burn ordinary house coal unless the appliance and complete flue system allow it. Always follow the appliance instructions and use only approved fuels.

Is a 125mm Flue Liner Suitable for Your Stove

A 125mm liner may suit an appliance that has approval for a 125mm flue. However, not every wood-burning or multifuel stove can use this diameter.

Do not choose the liner size from the stove outlet alone. Instead, check the appliance instructions and ask your installer to confirm the required diameter.

If the appliance does not have approval for a 125mm flue, the installation may need a 150mm liner. The fireplace opening and chimney design may also affect the required size.

About the Anti-Downdraught Pot Hanger Cowl

The included anti-downdraught pot hanger fits onto a suitable terracotta chimney pot. It supports the flexible liner and forms the chimney terminal.

Its fixed shape helps shield the outlet from changing wind directions. It also includes a guard that helps stop birds and larger debris from entering the flue.

Your installer must inspect the chimney pot before fitting the hanger. The pot must remain sound, secure and suitable for the fixing method. A cracked, loose or damaged pot may need repair or replacement.

Approval and Classification

• HETAS-listed flexible flue liner
• Classification: EN 1856-2 T450 N1 D V3 L50012 G
• Suitable for installation inside a compatible masonry chimney
• 125mm nominal internal diameter
• 904L stainless-steel inner and outer skins

The classification above covers the flexible liner. Other kit parts may have different ratings or fitting rules. Therefore, your installer must check the complete chimney system before starting work.

Installation Checklist

• Confirm that the appliance can use a 125mm liner
• Confirm that 904L steel suits the appliance and fuel
• Measure the full chimney route carefully
• Allow enough liner for the top and bottom connections
• Check that the liner can pass through the chimney
• Sweep the chimney before installation
• Check the chimney for damage or blockages
• Make sure the terracotta chimney pot remains sound and secure
• Check that the anti-downdraught cowl suits the property
• Read the appliance and liner instructions
• Use a suitably qualified installer

How to Install the Flexible Flue Liner

The installer will normally feed the liner down from the top of the chimney. The arrows printed on the liner must point upwards. These arrows show the direction of the flue gases.

First, attach the supplied nose cone to the leading end of the liner. Next, connect a suitable pulling rope to the nose cone. One person can then guide the liner from above while another person gently pulls it down the chimney.

Never force the liner through a blockage. Also, do not crush, twist or sharply fold it because this may damage its inner seam.

After positioning the liner, the installer can fit the pot hanger, ID plate and lower adaptor. A qualified installer should complete the work. Where required, use a HETAS-registered installer.

Manufacturer’s Warranty

The 904/904 flexible liner includes a manufacturer’s lifetime warranty. The supplied kit components include a 1-year manufacturer’s warranty. Warranty terms and conditions apply.

Correct installation, approved fuel use and regular maintenance may affect the warranty. You must also register the liner with the manufacturer. Failure to register may reduce the available liner warranty to one year.

Register your MI Flues liner warranty online

Keep your proof of purchase after registration. You may also need the installer’s details, installation date, appliance type, fuel, liner diameter and liner length.

Cleaning and Maintenance

Regular sweeping removes soot and other deposits from the chimney. It also allows the chimney sweep to check the liner and terminal for possible problems.

Sweep the chimney as often as the appliance and fuel require. A chimney serving a solid-fuel appliance normally needs sweeping at least once each year. However, frequent use may require more regular cleaning.

Only burn clean, dry and approved fuel. Wet wood and unsuitable fuel can create more deposits. They may also reduce performance and shorten the working life of the flue system.

Why Buy Your Flue Liner Kit from SNH Tradecentre

SNH Tradecentre works closely with MI Flues. Therefore, our team can help you choose a suitable liner diameter, stainless-steel grade and kit type.

We understand that installers often work to a fixed schedule. For this reason, we work closely with MI Flues to process orders quickly. When stock and ordering times allow, we aim to cut, check and dispatch liner kits on the same working day.

Same-day dispatch depends on stock, order checks and our daily cut-off time. We must also cut each liner to the selected length. Therefore, please order early if you need fast delivery.

• Genuine MI Flues liner and compatible parts
• Premium 904L stainless-steel construction
• Liner cut as one continuous length
• Matching 125mm kit components
• Close working relationship with MI Flues
• Same-day dispatch available on qualifying orders
• Helpful advice before ordering
• Established UK plumbing and heating merchant
• Trade counter in Birchington, Kent

Important Information Before Ordering

Please check the liner grade, diameter and length before completing your order.

We cut the flexible liner to the length you select. Therefore, you cannot return it after we cut or order it. This does not affect your rights if the product arrives faulty or does not match your order.

Your installer must confirm that the liner, anti-downdraught pot hanger, adaptor and all other parts suit the appliance and complete chimney design.