If you live in a low-energy house, a fully insulated house or just a new house, it may be necessary to supply air from the outdoors and directly into the stove. It may also be necessary if you have strong ventilation near your stove, for instance an exhaust hood. This external air supply is what we call AirSystem. All RAIS stoves are able to supply external air.
Without an external air supply, the stove uses air from the room for combustion. With AirSystem, air is taken from the outside, ensuring optimal combustion in your stove. The air supply to the system can be concealed by installing it either in the floor or in a wall behind the stove.