ᐅ Temperature in the Boiler Room (Air Source Heat Pump)

Hello,
down to what temperatures can it get in the heating room during winter?
I haven’t found any information about the ambient temperature range in which the indoor unit of my future air source heat pump (16 kW) can operate.
The building is a half-timbered house with 60 cm (24 inches) sandstone walls on the ground floor. Due to the slope of the site, the floor level of the heating room is about 30 cm (12 inches) below ground level. The house is currently undergoing a full renovation. The question is whether I should leave the heating room completely uninsulated (apart from the walls and ceiling adjoining the heated rooms), apply insulating plaster in the heating room (the heated rooms on the ground floor will get 8 cm (3 inches) insulating plaster), or even plan a heating circuit for the heating room. The room is about 25 m² (270 ft²) in size.
Are there any experiences with the temperature in the heating room when operating an air source heat pump?

Thank you very much for your input!
Egon der 3

My entire heat pump is actually installed outdoors, so it is a monoblock system. The indoor unit in a split system does not have any specific temperature requirements. Whether it is efficient to operate the hot water tank there at 5°C (41°F) is another question.

However, I would try to keep the room as warm as possible, as long as it can be done with reasonable effort.

I will also have a 200-liter (53-gallon) domestic hot water tank. The heat output of the indoor unit is therefore negligible, so without a heating circuit it could become uncomfortably cold. The washing machine will also be located in the room.

The washing machine is not affected if the room temperature is only 10°C (50°F). It just needs to be frost-free; anything beyond that is a bonus.