[wolvesechoes]

Well, I work for one of such corporations, doing modelling and simulation of HVAC/R systems, heat pumps included. You can believe or not, but there is not much competition there, unless you consider, for example, Carrier and Viessmann as separate manufacturers (and they are not since May 2023).

[tpm]

Nibe, Stiebel Eltron, IVT, Thermia, Vaillant, Daikin, IME, Hoval, Grubmann, Hitachi, Atlantic/Fujitsu, BDR Thermea, Mitsubishi Electric, I could probably find many more. Some are probably local to Central Europe, but that only reinforces my point.