Flue Adapter Vaillant Adapter 80/125 PP for Ventilation/Duct Connection

Flue Adapter Vaillant Adapter 80/125 PP for Ventilation/Duct Connection is a polypropylene transition piece designed to join round ducts of 80 mm and 125 mm diameters. Manufactured by Vaillant, this adapter enables a secure mechanical and airflow connection between pipes of different sizes used in domestic boiler flues and ventilation systems. The smooth internal surface and dimensional compatibility with standard round ductwork help maintain airflow efficiency while simplifying installation where size reduction or enlargement is necessary.

Advantages

The adapter is made from durable polypropylene (PP), offering chemical and corrosion resistance suitable for exhaust and ventilation applications. Its molded construction provides consistent dimensions for snug fits and reduced air leakage at joints. Lightweight and easy to handle, the adapter minimizes installation time compared with custom-fabricated transitions. Compatibility with commonly used round duct sizes ensures versatile use in residential HVAC and boiler flue connections.

Suitable for

• Connecting an 80 mm round duct to a 125 mm round duct in ventilation systems
• Adapting boiler flue pipes where a size transition is required
• Domestic HVAC ductwork modifications and repairs

Key specifications

• Material: polypropylene (PP)
• Connection diameters: 80 mm and 125 mm round
• Function: duct size transition / adapter for flue and ventilation
• Suitable environment: residential boiler flues and ventilation systems
• Weight: lightweight for manual handling (manufacturer standard)

How to use

Fit the larger end of the adapter onto the 125 mm duct and the smaller end onto the 80 mm duct, ensuring both ends are fully seated. Where required, apply appropriate sealing tape or silicone-approved sealant around the joints to improve airtightness and prevent condensate or exhaust leakage. Secure the connection with suitable clamps or fasteners compatible with PP material, and verify that the assembled run maintains proper slope and clearance according to the installation guidelines of the heating or ventilation equipment.

Usage recommendations

Use the adapter only in applications consistent with polypropylene material limits and local building codes. Avoid direct exposure to open flames or temperatures above the maximum operating range specified by the ventilation or boiler manufacturer. Inspect joints after installation and periodically during system maintenance to ensure seals and fastenings remain intact.