Altherma 3 Modulation

I wasn’t entirely sure which unit to use actually, I was trying to get at the fact that it would require let’s say a 3.5kW heater running constantly to match the heat loss of the house at -2. I know that over a day if you multiplied that by 24 it would be 84kWh of heat required as you say. So if I understand you correctly then yes I just meant 3.5kW!