Heat pumps come with a lot of restrictions. What about constant noise? Plus stating that they are cheap ain't correct. Our housing unit in Switzerland recently needed to replace older oil heater and one of the options was heat pump... which was by far the worst choice based on various criteria and we at the end voted for the oil again.
Sorry don't remember exactly, it was for 17 rather large apartments/semi houses (120-190m2), IIRC to the tune of 200k. Heat pumps would also require additional space to be put in, something we didn't have easily (not without some remodeling of whole area). They would be in the face of everybody's windows, another drawback combined with noise that was unavoidable as per proposition from vendor.
Another issue was that they were not available for a long time (around 6 months delivery time with no guarantee), something not relevant here but it also affected decision of owners.
Thanks for the info! Now it is much easier to understand your concerns. It is a rather big installation that you have here, in the range around 100kW (if both space heating and DHW are considered). Such systems (aka chillers) are usually installed away from buildings or on the rooftop if local regulations allow it.
