An asko hood ducted vs recirculating decision affects real day-to-day cooking performance far more than most kitchen designers give it credit for, and it is worth understanding clearly before choosing between Asko’s concealed hoods, like CBB861S and CBB862W, or its wall-mounted CW4934S, since the same hood body can sometimes support either configuration depending on how it is installed.
How a ducted hood works
A ducted hood pulls air, along with the grease, moisture, and odors carried in it, through a filter and then expels that air entirely outside the home through ductwork terminating at an exterior wall or roof vent. This is the more effective configuration for clearing steam and odor, since the air itself leaves the building rather than being filtered and returned. It does require a genuine duct path from the hood’s location to an exterior point, which is a real constraint on some kitchen layouts, particularly for an island installation far from an exterior wall.
How a recirculating hood works
A recirculating hood, sometimes described as ductless, pulls air through a grease filter and then through a secondary carbon or charcoal filter that adsorbs odor, before returning the filtered air back into the kitchen rather than venting it outside. This setup does not require any exterior duct run at all, which makes it far easier to install in a kitchen where ducting to an exterior wall is impractical or prohibitively expensive. The tradeoff is real: a carbon filter can reduce odor to a degree, but it does nothing to remove the moisture in steam, so a recirculating hood will never clear visible steam from a kitchen the way a properly ducted hood can.
Which Asko hoods support which configuration
Asko’s concealed hoods, built under cabinetry, and its wall-mounted models are both generally designed with ducted operation as the primary intended configuration, reflecting the airflow capacity figures published for them, such as the CC4525SAU’s maximum capacity of 670 cubic meters per hour and the CW4934S’s 700 cubic meters per hour rating. Confirming with your specific model’s installation manual whether a recirculating conversion kit is available is worth doing before assuming any hood can be run either way interchangeably.
Making the decision for your kitchen
If your kitchen layout allows a reasonably direct duct run to an exterior wall or roof, a ducted installation will consistently outperform a recirculating one at clearing both steam and odor, and it is worth the extra installation complexity for anyone who cooks with significant steam or oil regularly. If ducting genuinely is not feasible, a recirculating setup with a fresh carbon filter, replaced on schedule, is a reasonable second choice, with the clear understanding that steam clearing will be noticeably weaker than a ducted hood provides.
Browse our full Asko range hood model library to compare capacity ratings, or book an installation consultation at /schedule/. Extraction ratings for each hood are documented at global.asko.com.
