Hydraulic balancing air-water heat pump + efficiency circulation pump

If I am already low with the heating curve, why then limit the flow temperature further? It is already low due to the low curve. And what is meant by [Sockel]?

The base temperature is the desired room temperature, called the footpoint, which you have already set to 20 degrees.

That depends on the heating curve, which is just a calculated value for the respective outdoor temperatures.

If it should become too warm for you despite the lowest heating curve and the heat pump cannot compensate by modulating, one could try to force the heating below the heating curve by limiting the flow temperature.

As an example:
The heating curve would set a calculated flow temperature of 27 degrees at an outdoor temperature of 0 degrees and a desired room temperature of 20 degrees.
If that is already too warm for you, and you now limit the flow to 26 degrees, modern heaters usually recalculate the curve and adjust it.

Ah understood, thank you for the explanation

I have limited the flow temperature to 25 degrees with a gas heating system and set the lowest heating curve available.

The calculated flow temperature is then 22 degrees; the boiler runs until it reaches 27.5 and then turns off for several hours until the flow temperature falls below the target value.

My boiler now always operates at the lowest modulation it can (20% of the capacity) except when heating water.

This results in runtimes between 9 to 19 hours with 1 to 5 burner starts per day.

Consumption (150m2, standard energy saving regulation construction with improved wall insulation, controlled ventilation with heat recovery) ranges between 28 to 60 kWh depending on the hot water usage (bathtub or shower marathon).

Since we only moved in on 12.12, the values will probably decrease further as generally up to 25 percent more consumption is expected in the first 1-2 years.

That would basically be the compressor hysteresis for me, which I think I can set from 3k to a max of 15k; however, the compressor is then locked, and I have no influence on this lockout time.

Normally, the system regulates via the energy integral, which is fixed at -180 degree-minutes.

For every minute that the flow temperature (thanks to the compressor hysteresis) is above the flow setpoint temperature, the -180 moves towards 0. Accordingly, at 0, the compressor would switch off until the switched-on value (compressor start currently at -120) is reached. Unless the flow reaches the set max hysteresis before the energy integral is depleted; in that case, the compressor would be locked accordingly. Sounds kind of confusing, but I can't explain it any better.

So in summary

If the flow actual is above the flow setpoint, the 180-minute counter counts down to 0 (unless the compressor hysteresis intervenes earlier). If the flow actual is below the flow setpoint, it counts from 0 back up to 180, whereby the compressor switches on again at 120 and starts heating until the flow actual is above the flow setpoint again, and the cycle starts over.

I'm still struggling with my consumption data; I need to create a proper table for it. If I haven't made a mistake, compared to yesterday, I generated about 16.5 kWh less energy to maintain the temperature. However, the COP is worse (but that could be due to the hot water setting since I tried something today).