Yes, with the autarc software, you can calculate the heating load for multifamily homes as well. There are no limitations regarding the number of residential units when it comes to room-by-room heating load calculations according to DIN 12831.
However, when it comes to the dimensioning of heat pumps based on VDI 4645, there is a limitation to a maximum of 6 residential units. This restriction is specific to the calculation method outlined in VDI 4645 and should be taken into account during the planning process.