Shutdown difference of the heat pump?

Hello, I have a problem with my heat pump. Regarding the situation: My heat pump has recently been exceeding the setpoint value. That value is predefined. For example: This controller sets a target flow temperature of 30 degrees and turns the heat pump on. However, the heat pump keeps raising the temperature until the current shut-off differential of 43 degrees is reached. Then it lowers the temperature again. Why can't this heat pump deliver and maintain the setpoint requirement? Or is there no other way? Thank you very much for the advice.

Hey Seiler,
I am not an expert in this field, but usually a constant control is not possible.
An example: The house has a heating load of just 0.85 kW, which is the lower limit of the heat pump. However, this is sufficient to heat the water to 30 degrees Celsius. But the pump delivers 2 kW, so the water gets warmer than 30 degrees. If the controller were to switch off at this temperature, the water would cool down too quickly. This cycle would then repeat continuously.

BG

Hi Jonas,
Thank you very much for your explanation. If I understand correctly, it would not be good to reduce the shut-off differential. Otherwise, the heat pump will short cycle, right?
Best regards

That depends in my opinion on the heating or the heating load of the house. It can make sense to turn it down a bit. However, the heating and the house should be coordinated with each other.

In the cold winter, when higher temperatures are needed, the value can be higher. But it is already difficult to make the best setting here.

Hello, this could get really funny when it gets really cold. If the heat pump currently has to deliver 43 °C in the flow, then that is already questionable for me.

Does the heat pump also control the return flow?

Hello,
Thank you very much for the answers.

Here are some more infos.
Here are the two values that control the behavior of the heat pump:

1x the differential shutdown of the heat pump
1x the overshoot of the heat generator (i.e. heat pump) at the buffer tank. - I have now set this to 0 - meaning "setpoint buffer = setpoint heat pump" and not "setpoint buffer + overshoot = setpoint heat pump"

Let's see what this brings.

BG