Product Description

904/904 Solid Fuel Stainless Steel Flue Liner 5 Inch 125mm

Model: 904/904 Liner

Re-line a suitable masonry chimney with this 125mm 904/904 stainless-steel flexible flue liner. Both skins use durable 904L-grade stainless steel. Therefore, this premium liner suits demanding wood-burning and multifuel installations.

The double-skinned construction creates a strong and continuous flue route inside an existing chimney. It also has a smooth inner surface to help flue gases travel upwards efficiently.

The liner is suitable for compatible appliances burning wood, approved smokeless coal, coke, gas, oil or dry peat. However, you must check the appliance instructions and installation requirements before choosing the diameter.

904/904 Flue Liner Key Features

• 125mm internal diameter
• Also known as a 5-inch flexible flue liner
• 904L stainless-steel inner skin
• 904L stainless-steel outer skin
• Double-skinned flexible construction
• Designed for relining suitable masonry chimneys
• Suitable for compatible wood-burning and multifuel appliances
• Suitable for approved gas and oil applications
• Smooth inner skin supports an efficient flue-gas path
• Convoluted outer skin adds flexibility and strength
• Quattrolock folded seam construction
• HETAS-listed liner
• Manufacturer’s lifetime warranty, subject to registration and conditions
• Supplied in the selected made-to-measure length

125mm 904 Flue Liner Specification

• Product type: flexible chimney flue liner
• Nominal internal diameter: 125mm
• Imperial size: 5 inches
• Inner skin material: 904L-grade stainless steel
• Outer skin material: 904L-grade stainless steel
• Inner skin thickness: 0.105mm
• Outer skin thickness: 0.105mm
• Construction: double skinned
• Seam design: four-plane Quattrolock seal
• Application: relining an existing masonry chimney
• Pressure class: N1
• Temperature class: T450
• Declared classification: EN 1856-2 T450 N1 D V3 L50012 G
• Model: 904/904 liner

Suitable Fuels

• Cured dry logs
• Approved smokeless coal
• Coke
• Dry peat
• Gas
• Oil

Do not burn ordinary house coal unless the appliance and complete flue system specifically permit it. Always follow the appliance manufacturer’s fuel instructions.

Is a 125mm Flue Liner Suitable for My Stove?

A 125mm liner may suit appliances that have been tested and approved for a 125mm flue. However, many wood-burning appliances and installations require a 150mm liner.

Therefore, always check the appliance instructions, current Building Regulations and HETAS guidance before ordering. A competent installer should also confirm that the chosen liner will pass through the existing chimney.

If the appliance is not suitable for a 125mm flue, you may need a 150mm flexible flue liner. Never reduce the flue diameter below the size permitted by the appliance manufacturer or current regulations.

Flue Liner Construction

The smooth inner skin uses 0.105mm 904L-grade stainless steel. Meanwhile, the convoluted outer skin also uses 0.105mm 904L stainless steel.

The manufacturer forms the liner from a single strip of stainless steel. It bends the material through 180 degrees and folds the seam across four planes. As a result, the Quattrolock construction creates a strong and flexible liner for chimney installations.

Before Installation

• Confirm that 125mm is the correct diameter for the appliance
• Measure the complete chimney route before ordering
• Allow enough length for the required top and bottom connections
• Check that the liner can pass through the chimney
• Consider testing the route with a short section of the correct diameter
• Have the chimney swept and inspected
• Check that the chimney pot and stack remain in sound condition
• Select compatible adaptors, terminals and support components
• Check the direction arrows printed on the liner
• Use a suitable nose cone to help guide the liner

Flue Liner Installation Guidance

A suitably competent installer should fit the liner from the top of the chimney. The directional arrows on the liner must point upwards in the direction of the flue gases.

1. First, sweep and inspect the existing masonry chimney.
2. Next, confirm that the liner diameter will pass through the complete chimney route.
3. Secure a suitable rope to a compatible liner nose cone.
4. Attach the nose cone securely to the bottom end of the liner.
5. Check that the arrows point away from the nose cone and towards the chimney top.
6. Carefully feed the liner down from the top of the chimney.
7. At the same time, a second person should guide the rope from below.
8. Avoid sharp pulling, crushing or twisting the liner.
9. Once the liner reaches the required position, remove the nose cone.
10. Finally, connect and support the liner with approved, compatible components.

Always follow the manufacturer’s installation instructions and current Building Regulations. Where appropriate, use a HETAS-registered installer for the work.

What Is Included?

• 1 x selected length of 125mm 904/904 flexible flue liner

Please note: Adaptors, clamps, plates, cowls, nose cones and other installation components are not included unless the selected product option states otherwise.

Manufacturer’s Lifetime Warranty

This 904/904 flue liner carries a manufacturer’s lifetime warranty, subject to the manufacturer’s terms, correct installation, permitted fuel use and regular maintenance.

You must register the liner to activate the full warranty. Complete the MI Flues lifetime warranty registration form after installation.

Failure to register the product may reduce the manufacturer’s warranty to one year. Keep your purchase invoice and installation records, as the manufacturer may request them when handling a claim.

The registration may require:

• Customer’s name and installation address
• Installer’s name and HETAS registration details
• Installation date
• Appliance make and model
• Fuel type
• Liner diameter and installed length

Cleaning and Maintenance

Arrange regular chimney sweeping and inspection after installation. Chimneys serving solid-fuel appliances should be swept as often as the appliance, fuel and level of use require.

However, the chimney should normally be swept at least once each year. Some installations may need more frequent sweeping. Always follow the appliance manufacturer’s instructions and the advice of a qualified chimney professional.

Why Buy from SNH Tradecentre?

SNH Tradecentre is an independent plumbing and heating merchant based in Birchington, Kent. We supply flue products to homeowners, stove installers and trade customers across the UK.

In addition, we work closely with MI Flues to provide product support and process flue orders quickly. This close working relationship helps us dispatch many available orders on the same working day when they arrive before the relevant cut-off time.

• Experienced UK plumbing and heating merchant
• Close working relationship with MI Flues
• Fast processing of made-to-measure liner orders
• Same-day dispatch available on many orders, subject to stock and cut-off times
• Help selecting compatible liner components
• Support for homeowners and professional installers
• Secure online ordering

If you need help selecting the correct liner or installation components, call SNH Tradecentre on 01843 842727.

Important Information Before Ordering