Ceiling diffuser VIREO and plenum box ALX from Swegon make ceiling ventilation systems easy to design and install. High airflow capacity means you need fewer diffusers, reducing cost and complexity, improving visual appearance and saving valuable installation time.

Easy to design

The high airflow capacity of VIREO (up to 700 m³/h) allows you to design a system with fewer air diffusers than usual and still secure a good indoor climate. You save valuable working hours and reduce costs for your clients while at the same time providing visually pleasing ceiling ventilation that appeals to architects, property managers and users. Flush design further improves the visual appearance by giving a perfect alignment between VIREO and the ceiling. Adjustable slot nozzles, available in white or black, allow the air to swirl out along the ceiling, improving comfort and reducing energy consumption.

As always with Swegon, you get access to everything you need to do a good job such as CAD/DWG files, dimensioning tools, selection software, catalogues and HVAC expertise.

Easy to install

Less stress and more work done: That is what you get with VIREO and ALX. Fewer diffusers speed up installation time, and the wide airflow range makes it possible to use the same product type for many different applications. Purchasing becomes easier and you reduce the risk of mixing up units on the building site.

The ALX 360° rotatable plenum box means you can avoid unnecessary bends and pressure drops, saving time and securing a good installation. Quick Access functionality makes it easy to open and close the flush design front plate during installation, commissioning and maintenance. The plate will always be correctly aligned with no need for adjustment.

Explore the benefits

System Design



High airflow capacity 
Wide airflow range 
Flush design 
Dust protection covers 
Adjustable slot nozzles 
High airflow capacity 
Wide airflow range 
Rotatable plenum box 
Dust protection covers 
Quick access function 

Selection guide

VIREO and ALX is a combination that is easy to design and easy to install, and will do the job in most ordinary projects. For more demanding projects, you can consider exchanging the ALX plenum box for an ALS commissioning box, and/or using an EAGLE diffuser instead of VIREO for even more quiet and accurate ventilation. Look in the guide and choose the most suitable solution. Swegon’s high level of product quality, knowledge and support is always included.

      VIREO air diffuser with ALX plenum box    EAGLE Ceiling air diffuser with ALS commissioning box
Airflow capacity  
Airflow range    
Cooling and heating capacity    
Flexible air spread pattern    
Low noise level    
    ALX   ALS
Removable damper   No   Yes
Airflow measurement   No   Yes
Integrated insulation   No   Yes
Circular nozzle discs   No   Yes