Round Multi-Stage Duct Reducer AWENTA Fi 100/110/120/125/150 Rko 0004-00010-66759

Awenta round multi-stage duct reducer Fi 100/110/120/125/150 Rko 0004-00010-66759 is a stepped circular adapter designed to join ventilation ducts of different diameters. The component enables a single transition element to accommodate duct sizes 100, 110, 120, 125 and 150 mm, simplifying modifications and retrofits in HVAC installations. Constructed for compatibility with standard round ductwork, it supports routing and reconfiguration of airflow paths in residential and light-commercial ventilation systems.

Advantages

The multi-stage design removes the need for multiple separate reducers by integrating several stepped diameters into one compact unit. Its circular profile ensures secure, concentric connections that maintain duct alignment and reduce turbulence at transitions. The reducer is suitable for tight installation spaces and for projects where several possible connection diameters may be required during planning or maintenance.

Suitable for

• Connecting and adapting round ventilation ducts of 100–150 mm diameters
• Retrofitting existing HVAC runs where outlet or inlet sizes vary
• Temporary or permanent transitions during system testing and balancing
• Residential and small commercial ventilation systems

Key specifications

• Supported diameters: 100 mm, 110 mm, 120 mm, 125 mm, 150 mm
• Shape: circular / round stepped reducer
• Function: multi-stage stepped transition between duct sizes
• Application: air distribution and ventilation ductwork
• Compatibility: standard round ventilation duct connections

How to use

Select the stepped outlet matching the target duct diameter and slide the corresponding section into the mating duct. Ensure ends are fully engaged for a concentric fit and secure the connection with appropriate clamps, pop rivets, or duct tape according to site practice and material compatibility. Check for alignment and sealing at each transition to minimise air leakage and pressure loss. If necessary, use sealing compound or gasket material on joints to meet system performance requirements.

Usage recommendations

Use the reducer in applications where a single flexible solution for multiple diameters reduces inventory and installation time. Verify that the selected transition does not create excessive pressure drop for the system; when reducing diameter significantly, assess fan capacity and airflow to maintain required ventilation rates. Regularly inspect joints and seals during commissioning and maintenance to ensure continued air-tight performance.