Product Description

TWPro 125mm Twin Wall Insulated Connecting Pipe 1000mm Matt Black

Model: 37-125-025

Create a neat connection between a compatible heating appliance and a TWPro chimney with the TWPro 125mm Twin Wall Insulated Connecting Pipe. This 1000mm pipe includes an exposed telescopic connector at the lower male end. Therefore, it can connect directly to a suitable appliance outlet while keeping the installation clean and streamlined.

The supplied insulation and cover band fit around the exposed connecting section. In addition, the disconnecting design makes it easier to remove the appliance for servicing or replacement without taking apart the complete chimney.

Important: Always confirm that the appliance outlet, flue diameter and complete chimney design suit this component before ordering.

Key Features

• 125mm internal flue diameter
• 1000mm nominal pipe length
• Built-in telescopic appliance connector
• Designed to connect directly to a compatible heating appliance
• Supplied with insulation for the connecting section
• Includes a cover band for a neat finished appearance
• Disconnecting section helps with future appliance removal
• Creates a clean transition from the appliance to insulated twin-wall flue
• Matt-black powder-coated finish
• 316L-grade stainless-steel inner casing
• 304-grade stainless-steel outer casing
• 25mm high-density mineral-wool insulation
• Push-fit joint with locking band
• Compatible with TWPro and corresponding KW Flue components
• Product model: 37-125-025

TWPro 125mm Connecting Pipe Specification

Read: Why We Think TWPro Twin-Wall Flue Is the Best

• Download the TWPro Information Sheet
• Download the TWPro Installation Sheet
• Brand: TWPro
• Product type: insulated appliance connecting pipe
• Nominal internal diameter: 125mm
• Approximate external diameter: 175mm
• Nominal pipe length: 1000mm
• Lower connection: exposed telescopic connecting section
• Finish: matt black
• Inner casing: 0.4mm 316L-grade stainless steel
• Outer casing: 0.4mm 304-grade stainless steel
• Outer coating: heat-resistant matt-black powder coating
• Insulation: 25mm injected mineral wool
• Insulation density: approximately 190kg/m³
• System joint method: push fit with locking band
• Maximum operating-temperature class: T600
• Declared distance to combustible materials: 50mm
• Product model: 37-125-025

What Is Included?

• 1 x TWPro 125mm Twin Wall Connecting Pipe
• 1 x built-in telescopic appliance connector
• Insulation for the exposed connecting section
• 1 x matching cover band
• Matt-black finish
• Model: 37-125-025

Application

This component provides a direct transition between a compatible heating appliance and a 125mm TWPro insulated chimney. As a result, it can remove the need for a separate length of visible single-wall connecting pipe in a suitable installation.

Subject to the appliance and chimney-system instructions, suitable applications may include:

• Wood-burning stoves
• Multifuel stoves
• Other compatible solid-fuel appliances
• Compatible gas appliances
• Compatible oil-fired appliances

Always check the appliance manufacturer’s instructions. In particular, confirm the outlet size, flue direction, chimney classification and permitted connection method.

Built-In Telescopic Appliance Connection

The lower male end includes an exposed telescopic connecting section. This section fits into a compatible appliance outlet and helps installers achieve the required connection height.

Once the installer sets the connection correctly, the supplied insulation covers the exposed area. The outer cover band then fits around the joint to provide a neat and streamlined appearance.

The available movement must remain within the limits stated by the manufacturer. Therefore, do not extend the connector beyond its approved adjustment range.

Easy Appliance Removal

The disconnecting section can make future appliance removal easier. For example, an installer may need to remove the stove for servicing, repair or replacement.

The telescopic connection allows movement at the appliance outlet. As a result, the installer may not need to dismantle long sections of the twin-wall chimney above it.

However, only a suitably competent person should disconnect or refit the appliance. They must also inspect the flue connection before the appliance returns to use.

A Clean and Streamlined Installation

This connecting pipe allows the insulated TWPro chimney to continue down towards a compatible appliance. Therefore, it can create a more consistent appearance than an installation with a long section of exposed single-wall stove pipe.

The matching matt-black cover band conceals the insulated connecting area. Consequently, the finished installation looks neat while retaining the practical benefits of a removable appliance connection.

TWPro System Construction

• Inner casing: 0.4mm 316L-grade stainless steel
• Outer casing: 0.4mm 304-grade stainless steel
• Outer finish: matt-black powder coating
• Insulation: 25mm injected mineral wool
• Insulation density: approximately 190kg/m³
• Joint system: push fit with locking band
• Maximum operating-temperature class: T600

The 316L stainless-steel inner casing provides a durable route for flue gases. Meanwhile, the mineral-wool insulation helps retain heat inside the chimney. The matt-black outer casing then provides protection and a smart finish for visible installations.

Approvals and System Classification

• Forms part of a HETAS-approved chimney system
• EN 1856-1 T600 N1 W V2 L50040 G50
• EN 1856-1 T200 P1 W V2 L50040 O20
• Suitable for compatible negative-pressure applications up to T600
• Suitable for compatible positive-pressure applications up to T200

The correct classification depends on the appliance, fuel and complete chimney design. Therefore, check the rating of every component before installation.

Distance to Combustible Materials

The declared minimum distance from the TWPro insulated chimney to combustible materials is 50mm under its T600 G50 classification.

However, the appliance or another part of the installation may require a greater clearance. Always follow the largest distance stated in the complete installation instructions.

The 50mm clearance applies to the correctly assembled insulated TWPro chimney. Different requirements may apply around the appliance outlet and exposed connecting section.

Installation Guidance

• Confirm that the appliance accepts a direct twin-wall connection
• Check that the appliance outlet suits the 125mm connector
• Confirm the required adjustment before fitting
• Keep the telescopic section within its permitted range
• Fit the supplied insulation around the exposed connection
• Secure the outer cover band correctly
• Push the upper TWPro joint fully together
• Fit the required locking band
• Keep the chimney vertical and correctly supported
• Do not allow the appliance to carry the chimney’s full weight
• Maintain all required distances from combustible materials
• Follow the appliance and TWPro installation instructions

A suitably competent installer should design and fit the complete chimney system. For solid-fuel installations, use a HETAS-registered installer where appropriate.

Supporting the Chimney

The connecting section allows the chimney to meet the appliance, but it should not replace the required structural supports. Instead, suitable TWPro support components must carry the weight of the chimney.

Correct support also helps prevent unwanted downward or sideways pressure on the appliance outlet. Therefore, check the full chimney route and support positions before starting the installation.

Compatibility

This connecting pipe fits the 125mm TWPro and corresponding KW Flue systems only. Other twin-wall chimney brands may use different joint sizes, profiles and locking methods.

Therefore, do not connect this pipe to another manufacturer’s system unless written technical approval confirms compatibility.

The stated 125mm measurement refers to the internal flue diameter. Because TWPro has 25mm of insulation around the inner casing, the external pipe diameter is approximately 175mm.

Can the Connecting Pipe Be Cut?

Do not cut or alter this component unless the manufacturer’s instructions clearly permit it. Cutting the pipe may damage the stainless-steel casings, insulation or telescopic connection.

In addition, an unapproved alteration may affect the product classification, safety and warranty. Instead, select suitable standard or adjustable TWPro components to achieve the required chimney height.

Inspection and Maintenance

Inspect the appliance connection, insulation, cover band and adjoining locking band during routine chimney maintenance. Make sure each part remains secure and free from damage.

Arrange chimney sweeping at intervals that suit the appliance, fuel and frequency of use. Also replace any component that becomes damaged, distorted, heavily corroded or insecure.

If the appliance is removed, the installer should inspect and correctly refit the complete connection before using the appliance again.

TWPro Warranty

• 25-year system warranty, subject to the manufacturer’s conditions
• 2-year warranty on the painted finish

Correct product selection, installation, fuel use and maintenance may affect warranty cover. Therefore, follow the manufacturer’s instructions and keep your proof of purchase.

Why Choose the TWPro Twin-Wall System?

TWPro combines a 316L stainless-steel inner casing with dense mineral-wool insulation and a durable matt-black outer casing. In addition, its push-fit joints and locking bands help installers create a secure and tidy chimney route.

This connecting pipe also provides a practical link between the appliance and insulated chimney. As a result, it can help create a cleaner appearance while allowing easier appliance removal when required.

Why Buy from SNH Tradecentre?

• Specialist supplier of chimney, flue and stove products
• Wide range of matching 125mm TWPro components
• Practical product advice from an experienced team
• Close working relationship with MI Flues
• Fast nationwide UK delivery options
• Secure online ordering
• Support before and after your purchase

SNH Tradecentre works closely with MI Flues to process TWPro orders quickly. As a result, we can often arrange same-day dispatch on eligible in-stock orders placed before the relevant cut-off time.

Stock levels, order size and delivery location may affect dispatch times. Therefore, contact us before ordering if you need the component urgently.

Need help confirming whether this connecting pipe fits your appliance? Call the SNH Tradecentre team on 01843 842727.

Frequently Asked Questions

What is this TWPro connecting pipe used for?

It connects a compatible heating appliance directly to a 125mm TWPro insulated chimney. Its built-in telescopic section also helps create a neat and removable connection.

How long is the pipe?

The pipe has a nominal length of 1000mm. Check the manufacturer’s full dimensions and adjustment range when planning the installation.

What diameter is the flue?

The pipe has a nominal internal diameter of 125mm, which is approximately 5 inches. Its external diameter is approximately 175mm.

Does it connect directly to a stove?

It can connect directly to a compatible appliance outlet. However, always check that the appliance manufacturer permits this type of connection.

What is the telescopic section for?

The telescopic section helps the installer connect the pipe to the appliance and allows movement when the appliance needs to be removed.

Are the insulation and cover band included?

Yes. The component includes insulation and a cover band for the exposed connecting section.

Can it make appliance servicing easier?

Yes. The disconnecting section can help an installer remove the appliance without dismantling large parts of the chimney system.

Can it be used with a wood-burning stove?

Yes, it may connect to a compatible wood-burning or multifuel stove. Check the appliance instructions and use a suitably competent installer.

Does it fit other twin-wall chimney brands?

No. It is designed for compatible 125mm TWPro and corresponding KW Flue components. Do not mix it with another brand unless the manufacturer confirms compatibility.

How far must it remain from combustible materials?

The declared clearance for the correctly assembled insulated TWPro chimney is 50mm under its T600 G50 classification. Different requirements may apply around the appliance connection, so always follow the complete installation instructions.

Can the pipe support the weight of the chimney?

No. Use the correct TWPro support components to carry the chimney. The appliance outlet and telescopic connector should not carry the full chimney load.