new heat pump as a replacement for oil heating with existing radiators

Think about it: what experiences do you expect from a company that has only existed for about a year?

Thank you, you are of course right, but it was worth a try

@ Thank you, I find your contribution highly efficient. And if we could deepen this a bit, it would really help me a lot. Therefore, here are some further details: We do not have underfloor heating. In each room, there are 1-2 wall radiators; with oil and the mentioned annual consumption, we and the tenant (medical practice) had it cozy and warm. It is a Bien-Zenker house (prefabricated house), which we built in 1990. At that time, the insulation was state of the art. A heat load calculation was made by the DWW representative for each room.
COP 4.9, living area 316 sqm
Estimated heat demand 58,860 kWh
Heat load according to DIN EN 12831 115.2 kW
Required electricity 13,213.47 kWh
Pump rated power 12.3 kW
Refrigerant R32

For the building survey, each room is specified with many properties in the offer:
Floor area, exposed perimeter, room height, room area, room volume, room envelope area, exposed perimeter, minimum outdoor air exchange, minimum outdoor air exchange, infiltration, ALD, adjacent temperature, U-value, heat loss, thermal bridge surcharge, and much more.
In 5 of 10 rooms, an indoor unit with air-to-air heat pump for heating and cooling is planned (AERO duo comfort).
I have gathered other offers, but all are far above the price from DWW (after KfW €21,000); the highest (operation nearby) was €60,000 (which I unfortunately cannot afford).

What is your gut feeling?
Best regards
Norbert

That then makes 48 W/m², but 4200 full operating hours. So the pump runs at full power for half a year. Or the oil burner heated the surroundings more than the rooms.

estimated heating demand 58,860 kWh

That matches the oil consumption, but not the 49 W/m². What heating demand and heating load have the competitors assumed? Why actually additional air indoor units, if it was nicely warm with the radiators?

Because the heat pump is too small