Product Description

TWPro 125mm Adjustable Connecting Pipe with 45 Degree Bend Matt Black

Model: 37-125-027

Connect a compatible heating appliance to a TWPro chimney while changing the flue direction with the TWPro 125mm Adjustable Connecting Pipe with 45 Degree Bend. This 500mm insulated starter pipe combines an integrated 45° bend with an exposed telescopic connector at the lower male end.

The telescopic section allows the installer to make the final connection to a suitable appliance outlet. Meanwhile, the supplied insulation and cover band conceal the connecting area and create a clean, streamlined finish.

The disconnecting section also helps make future appliance removal easier. Therefore, an installer may be able to service or replace the appliance without dismantling large sections of the chimney.

Important: Always confirm that the appliance manufacturer permits a direct insulated twin-wall connection and that the built-in 45° bend suits the proposed chimney route.

Key Features

• 125mm internal flue diameter
• 500mm nominal connecting-pipe length
• Built-in 45-degree bend
• Exposed telescopic connector at the lower male end
• Designed to connect directly to a compatible appliance
• Supplied with insulation for the connecting section
• Includes a matching matt-black cover band
• Disconnecting section helps with appliance removal
• Combines a starter pipe and bend in one component
• Helps reduce the number of separate joints
• 316L-grade stainless-steel inner casing
• 304-grade stainless-steel outer casing
• 25mm high-density mineral-wool insulation
• Push-fit connection with supplied locking band
• Compatible with TWPro and corresponding KW Flue components
• Product model: 37-125-027

TWPro 125mm Adjustable 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
• Manufacturer: MI Flues
• Product type: adjustable insulated starter and connecting pipe
• Nominal internal diameter: 125mm
• Approximate external diameter: 175mm
• Nominal pipe length: 500mm
• Built-in bend angle: 45 degrees
• Lower connection: exposed telescopic appliance connector
• Finish: matt black
• Inner casing: 0.4mm 316L-grade stainless steel
• Outer casing: 0.4mm 304-grade stainless steel
• Outer coating: high-temperature matt-black finish
• Insulation: 25mm high-density mineral wool
• Joint method: push fit with locking band
• Maximum operating-temperature class: T600
• Declared distance to combustible materials: 50mm
• Product model: 37-125-027

What Is Included?

• 1 x TWPro 125mm Adjustable Connecting Pipe
• 1 x integrated 45-degree bend
• 1 x built-in telescopic appliance connector
• Insulation for the exposed connecting section
• 1 x matching cover band
• 1 x TWPro locking band
• Matt-black finish
• Model: 37-125-027

Application

This component provides a direct transition between a compatible heating appliance and a 125mm TWPro insulated chimney. At the same time, its integrated 45° bend changes the direction of the chimney route.

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 required flue diameter, permitted connection type and maximum number of bends within the complete chimney route.

Built-In 45 Degree Bend

The integrated 45° bend allows the chimney to change direction directly above the appliance. Therefore, the component can help align the appliance outlet with a chimney route that does not rise vertically from the same centre point.

Because the bend and connecting pipe form one component, the installation needs fewer separate fittings and joints. As a result, the finished chimney can look cleaner and more streamlined.

However, the installer must still calculate the offset correctly. Check the manufacturer’s dimensions and available installation space before ordering.

Telescopic Appliance Connection

The lower male end includes an exposed telescopic connecting pipe. This section fits into a compatible appliance outlet and allows the installer to complete the final connection.

Once the installer sets the connection, the supplied insulation fits around the exposed section. The matt-black cover band then conceals the joint and creates a neat finished appearance.

Keep the telescopic connector within the adjustment limits shown in the manufacturer’s instructions. Do not extend it beyond the permitted range.

Easy Appliance Removal

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

The telescopic section provides movement at the appliance outlet. Therefore, the installer may not need to dismantle the complete chimney above the appliance.

Only a suitably competent person should disconnect or refit the appliance. They must also inspect the chimney joint before returning the appliance to use.

A Cleaner Stove Installation

This connecting pipe allows the insulated TWPro chimney to continue down towards a suitable appliance. Therefore, it can reduce the amount of visible single-wall stove pipe within the installation.

The integrated bend also removes the need to combine a separate starter pipe and 45° bend. Consequently, the installation can have fewer visible joints and a more consistent matt-black finish.

Planning the Offset

Before ordering, measure the horizontal and vertical distance between the appliance outlet and the planned chimney centre line. In addition, allow enough space for the outside diameter of the insulated pipe.

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

Also check that the pipe, cover band and bend will remain clear of the appliance body, nearby walls and combustible materials.

TWPro System Construction

• Inner casing: 0.4mm 316L-grade stainless steel
• Outer casing: 0.4mm 304-grade stainless steel
• Outer finish: high-temperature matt-black coating
• Insulation: 25mm high-density mineral wool
• 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 correctly assembled TWPro insulated chimney to combustible materials is 50mm under its T600 G50 classification.

However, different requirements may apply around the appliance outlet and exposed telescopic connection. The appliance or another part of the installation may also require a greater clearance.

Always follow the largest distance stated in the appliance and chimney instructions.

Installation Guidance

• Confirm that the appliance permits a direct twin-wall connection
• Check that the appliance outlet suits a 125mm connector
• Confirm that the 45-degree bend suits the chimney route
• Measure the required offset before installation
• Keep the telescopic section within its approved adjustment range
• Fit the supplied insulation around the exposed connection
• Secure the cover band correctly
• Push the upper TWPro joint fully together
• Fit the supplied locking band
• Support the chimney independently from the appliance
• 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 telescopic connector joins the chimney to the appliance, but it should not carry the full weight of the chimney.

Instead, use the correct TWPro base support, wall supports, ceiling supports or other approved load-bearing components. Correct support helps prevent unwanted weight and sideways force from reaching the appliance outlet.

The change in direction may also require support above the bend. Follow the current TWPro installation instructions when planning the support positions.

Compatibility

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

Therefore, do not connect it to another chimney brand unless the manufacturer confirms compatibility in writing.

Also check the appliance outlet carefully. A 125mm chimney component will not automatically fit every nominal 125mm appliance outlet without the correct approved connection.

Can the Pipe Be Cut?

Do not cut or alter this component unless the manufacturer’s instructions clearly permit it. Cutting may damage the inner casing, outer casing, insulation or telescopic connection.

An unapproved change may also affect the product classification, safety and warranty. Instead, select suitable standard or adjustable TWPro components to complete the chimney route.

Inspection and Maintenance

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

Arrange chimney sweeping at intervals that suit the appliance, fuel and frequency of use. The installer must also ensure that the complete chimney provides suitable cleaning and inspection access.

If the appliance is removed, inspect and correctly refit the connection before returning it to use.

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 neat and secure chimney route.

This specialist connecting pipe combines adjustment, a 45° bend and an appliance connection within one component. As a result, it can reduce the number of separate fittings needed near the stove.

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 this component urgently.

Need help checking whether the bend and connector suit your stove? 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 while also changing the chimney direction through 45 degrees.

How long is the connecting pipe?

It has a nominal length of 500mm. Check the manufacturer’s dimensional drawing when calculating the final height and offset.

Is the 45-degree bend built into the pipe?

Yes. The component combines the connecting pipe and 45° bend within one unit.

What does the telescopic section do?

It allows an installer to make the final connection to a compatible appliance outlet. It can also provide movement when the appliance needs to be removed.

Are the insulation and cover band included?

Yes. Insulation and a matching cover band are supplied for the exposed telescopic connecting section.

Is a locking band included?

Yes. A compatible TWPro locking band is supplied for the push-fit chimney connection.

Can this pipe connect directly to a wood-burning stove?

It can connect directly to a compatible stove when the appliance manufacturer permits this type of connection. Always check the appliance instructions first.

Does the connector support the chimney?

No. The chimney needs suitable load-bearing and lateral supports. Do not allow the appliance outlet or telescopic connector to carry the complete chimney weight.

What diameter is the pipe?

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

Does it fit other twin-wall chimney brands?

No. It is designed for compatible TWPro and corresponding KW Flue components. Do not mix chimney brands unless the manufacturer confirms compatibility.

How far must the pipe remain from combustible materials?

The declared clearance for the correctly assembled insulated chimney is 50mm under its T600 G50 classification. Different requirements may apply around the appliance connection.