Extraction device and method for operating the same

An extraction device for removing heated air from an area above a cooking hob, the extraction device configured to be installed within a cabinet beneath the hob and to draw a downdraft air flow from the area above the cooking hob, the extraction device comprising an inlet communicating with an opening in a worktop surface of the hob, an outlet communicating with a space within said cabinet when the extraction device is installed therein, and each of the following along an air channel from said inlet to said outlet for the air drawn into the inlet from the area above the cooking hob:

• a grease filter disposed at or downstream of the inlet,
• a heat pump unit downstream of the grease filter,
• a fan downstream of the heat pump unit,
• a carbon odor filter downstream of the fan, and
• a drip tray;
• the heat pump unit comprising a cold area heat exchanger compartment located upstream of a hot area heat exchanger compartment, a border therebetween, and a common closed-loop cooling circuit adapted to circulate a coolant through both the cold-area and hot-area heat exchange compartments, the cooling circuit comprising:
• a compressor adapted to compress and thereby heat the coolant in connection with transitioning said border into the hot area heat exchanger compartment through the cooling circuit,
• an evaporator adapted to expand and thereby cool the coolant in connection with transitioning said border into the cold area heat exchanger compartment through the cooling circuit,
• a cold area heat exchanger in the cold area heat exchanger compartment, and
• a hot area heat exchanger in the hot area heat exchanger compartment;
• wherein the cold area heat exchanger compartment is configured to cool the heated air drawn from the area above the hob via heat-exchange with the coolant in the cold area heat exchanger to thereby induce condensation and separation of at least a portion of water and/or grease in the air;
• and the hot area heat exchanger compartment is configured to reheat the air from the cold area heat exchanger to raise its capacity for carrying fluid and thus reduce a relative humidity thereof prior to the air being exhausted into the space within the cabinet via said outlet;
• said drip tray being configured to collect said condensate.