The right mode for every space configuration

Extraction mode: highly efficient
Extraction mode rangehoods draw the cooking vapours in and remove grease particles with the help of the grease filter. The filtered air is then transported out of the kitchen via vent ducting. Along with the filtered air, any excess moisture and odours are removed from the kitchen. In order to channel the extracted air outside, extraction mode rangehoods need ducting and a wall or roof vent. At the same time, a flow of fresh air must be provided, for instance through an open window. Extraction rangehoods are particularly recommended above gas cooktops as well as for frequent deep-fat frying, grilling or use of the wok. This type of cooking generates a lot of heat, grease and steam which these rangehoods remove most efficiently. At the same time gas cooktops are provided with an adequate supply of fresh air for combustion.
Extraction mode with external fan: effective, quiet
Extraction mode rangehoods can be fitted with an external motor located on an outside wall or on the roof, for example. Installing the motor externally means that it can be located where the noise will cause less disturbance. This reduces the noise level to a minimum. For a significant reduction in noise levels, the ducting system should be at least 5-7 m long. Whether you are able to use an external motor will depend on the layout of the kitchen, the type of ducting and how it is installed and the rangehood itself. 
Recirculation mode: simple and energy-efficient
Recirculation cooker hoods draw in steam and vapours and remove grease and odours by using grease and charcoal filters. The cleaned air is then redirected back into the kitchen. This air circulation takes place within the room. Recirculation rangehoods do not require ducting systems, or holes to be drilled in walls or ceilings. Recirculation mode rangehoods are very easy to install and are very often the only option available because of building constraints (for example, in blocks of flats). A recirculation rangehood is suitable for installation above a HiLight or induction cooktop. Over a gas cooktop, however, where lots of heat is created, an extraction hood should be installed if possible.
Images serve as examples to illustrate the product benefit. Actual feature may vary per model.