Vaillant 1970mm 60/100mm Flue Extension | 303905 | Push-Fit

Description

The Vaillant 1970mm flue extension is a genuine 60/100mm concentric air/flue duct designed to extend compatible Vaillant boiler flue systems. It provides installers with greater flexibility when routing a horizontal or vertical flue around building constraints, helping achieve a compliant termination position without compromising system performance.

Manufactured in durable polypropylene (PP), this 2 metre nominal extension uses Vaillant’s push-fit flue system for straightforward assembly. It is suitable for use between flue components such as elbows, vertical adaptors and terminals, and can be shortened on site where the installation requires a precise length.

1970mm

Extension length

60/100mm

Concentric duct

PP

Polypropylene construction

Push-fit

Connection system

303905

Manufacturer part number

H&V

Horizontal or vertical use

Safety and installation: Flue systems must be installed by a competent person in accordance with the boiler manufacturer’s instructions and applicable UK regulations. Always confirm the permitted flue length, support requirements and termination position for the specific boiler before installation.

Compatibility note: This extension is intended for compatible Vaillant 60/100mm concentric flue systems. Check the boiler model, flue configuration and maximum permitted duct length before ordering.

Installer tip: The duct can be shortened where required. Support each extension with a suitable pipe clamp and follow the flue manufacturer’s guidance on gradients, joints and maximum unsupported lengths.

Key Features

Extended Flue Reach

Adds up to 1970mm of duct run, giving greater freedom to position the boiler and achieve a suitable flue termination.

60/100mm Concentric Design

The 60/100mm diameter concentric duct combines the air intake and flue gas discharge within one system.

Durable Polypropylene

Constructed from PP, a robust material suited to modern condensing boiler flue applications.

Push-Fit Assembly

Designed for Vaillant’s push-fit flue system, supporting efficient installation and secure joint assembly.

Horizontal or Vertical Use

Suitable for use in compatible horizontal and vertical flue installations, including runs between elbows and vertical components.

Can Be Shortened

The extension can be cut to length on site, allowing a neater fit where a full 1970mm run is not required.

Technical Specifications

Product Identification

Brand

Vaillant

Manufacturer part number (MPN)

303905

EAN

4024074398043

Product type

Concentric air/flue duct extension

Dimensions and Construction

Nominal length

1970mm (2.0m nominal extension)

Duct diameter

60/100mm concentric

Material

Polypropylene (PP)

Colour

White

Installation and Compatibility

Connection type

Push-fit

Installation orientation

Horizontal or vertical, where compatible

Typical use

Between flue elbows, vertical adaptors and vertical terminals

Compatibility

Compatible Vaillant 60/100mm concentric flue systems

Frequently Asked Questions

What is the length of this Vaillant flue extension?

This extension provides a duct length of 1970mm. It is commonly described as a 2 metre or 2.0m flue extension.

Which flue size does it suit?

It is designed for 60/100mm concentric air/flue systems, with a 60mm inner flue duct and 100mm outer air duct.

Can the extension be cut to size?

Yes. The extension can be shortened on site where the required flue run is less than the full 1970mm length. Follow the boiler and flue installation instructions when cutting and assembling the system.

Can it be used horizontally and vertically?

Yes, it is suitable for compatible horizontal and vertical Vaillant flue installations. The final configuration must comply with the permitted flue route and maximum length for the boiler being installed.

Does it need additional support?

Yes. Flue extensions should be adequately supported with suitable pipe clamps, following the spacing and fixing requirements set out in the relevant Vaillant installation instructions.

Who should install this product?

A competent heating engineer should install the flue extension in line with the boiler manufacturer’s instructions and applicable UK building and gas safety requirements.

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