According to § 2 MFeuV (Model Combustion Ordinance), a fireplace is considered to be dependent on indoor air if its combustion air is obtained entirely or proportionately from the location of the fireplace or from other indoor spaces. According to § 3 MFeuV, the combustion air supply for a room air-dependent fireplace is considered sufficient if the following spatial requirements for the installation site are met.
Spatial requirements for the installation site for indoor air-dependent fireplaces in accordance with § 3 MFeuV:
*Combustion air network here is the network between the location of the fireplace and adjacent rooms with a connection to the outside. The connection must be made via combustion air openings of ≥ 150 cm² between the rooms. Total volume of the rooms of the combustion air network (only rooms with connection to the outside): ≥ 4 m³ per 1 kW nominal power of the fireplace.
The requirements do not apply to open fireplaces. The sufficient supply of combustion air to a room-air-dependent fireplace can also be proven differently on an individual basis in accordance with § 3 FeuV.
Combustion air openings or ducts:
Combustion air openings or ducts that supply a fireplace with the supply air required for its operation must not be closed or blocked. Alternatively, safety devices such as sensors can also ensure that the fireplace can only be operated when there are free openings or pipes. The required cross-section must not be reduced further, e.g. by means of grids or closures.
Simultaneous operation of ambient air-dependent fireplaces and room air extraction systems:
According to § 4 MFeuVO, when room air extraction systems and a room-air-dependent fireplace are operated at the same time, it must be ensured that no flue gases from the fireplace enter the living rooms through the parallel running fan, which in the worst case can lead to poisoning of the residents. A room air extraction system can be, for example, an electric room ventilation, a warm air heating system, an extractor hood or an exhaust air tumble dryer.
For each operating status of the respective system, it must be ensured that no negative pressure can be created in the installation room of the fireplace. Measures for this can include:
Source: bauwion
