Ventilation for oil heating must be ensured...

We are getting an oil heating system in our house. The chimney sweep has now said that regular ventilation from outside to inside must be ensured. That means a hole in the outer wall or the basement window. The heating technician says this is wrong because cold air should not be supplied to the basement, as this increases the energy consumption of the heating system. He has therefore suggested a connection. That means a grille in the heating cellar door so that the adjacent room is also used. For a 22 KW heating system, that would be sufficient. The chimney sweep says this is not enough. Can someone tell me something about this, also where to find information about such guidelines. I have by now found out that this differs from region to region. We are in the Taunus (Hessen).

You won't get the better of the chimney sweep; he is all-powerful in his domain. Try to negotiate a channel as a compromise.

What do you mean by a channel? From where to where?

Outdoor air supply for heating systems either through an opening with a fly screen in the glazing of the basement window (such panes are available as standard products) or ventilation duct, i.e. breakthrough through the basement wall to the outside and duct (PVC pipe or similar) to ground level or led laterally into the window well. Closure again with fly screen.