Air-water heat pump current consumption and data

Does hysteresis now also apply upwards for you? So shutdown only at 58 degrees? That would be an expensive affair daily with an air-to-water heat pump.

No, that would be nonsense. After consulting with the heating engineer, I have now activated the legionella protection once a week. This heats the hot water up to 60°C.

If circulation is present, it must run regularly, afaik even mandatory due to stagnation in the pipe. The point is not to kill existing legionella (high temperature required) but to prevent them from forming in the first place.

Is this the overcurrent valve that is so criticized here? At least the hydraulics go directly from the supply line into the buffer tank in the return line.

It was set to 150mbar - I set it to 250 and already more flow reached the upper floor. Continue?

If all (or at least most) heating circuits/radiators are on and will definitely stay that way: to do.

150mbar seems very low. The air-water heat pump pump generates 640mbar after all?! Can it be completely shut off or is 300mbar the maximum? Did you actually get an additional pump?