Experiences with brine heat pump

Hello,
a further setback is not recommended for a well-insulated house. Basically, only your heat storage - the screed - cools down, and this then has to be compensated for again. On normal nights this should not actually make much difference, only when it is very cold, it tends to be negative because after the setback there will be very long cycles, causing the brine to become somewhat colder.

The most important thing will be to optimally adjust the heating system and heating curve to the house. Especially with the thermostats, I can well imagine that the heat pump / the flow rate is often "choked." Best is – now is almost the optimal time of year (as soon as it gets a bit cooler) – to adapt the heating curve to the house (since this is a longer process, it is best to do it yourself). It was also important for me to set the hysteresis higher so that the heat pump does not cycle too often.

If the heat pump's capacity fits the house well, that is the most important thing; other settings are rather secondary (possibly lower the hot water temperature).

Otherwise, I would find it interesting what "the first error in the system" was (or was that independent of the question)?

There is also the argument the other way around, that the night setback does make sense because otherwise the heat pump heats against the low outside temperature at night. Maybe the truth lies somewhere in the middle (slight setback at night with the goal of maintaining the temperature in the house, not lowering it)?

Night setback does make sense, because otherwise the heat pump heats against the low outside temperature at night.

The argumentation has a certain logic in my opinion, but only applies to air-water heat pumps, at most also to the surface collector. The brine temperature in deep drilling should not have a daily cycle, or am I overlooking something?

There is also the argument the other way around, that the night setback does make sense because otherwise the heat pump heats against the low outside temperature at night. Perhaps the truth lies somewhere in the middle (a slight setback at night with the goal of maintaining the temperature in the house, not lowering it)?

In addition to Kekse's arguments, there is also the fact that - if you want to bridge the dark/cold night in winter - the heat pump would have to be turned off for a relatively long time, and then you would need very long operating times in one go. With air-to-water heat pumps, there is the problem of icing, with ground-source heat pumps, the brine temperature drops slightly during long operating times because the environment around the probe in the ground cools down. At least with my brine system, I do not have a daily cycle; that is precisely the advantage, that you are largely independent of air/outside temperature. For me, the difference between the start and end of winter is even less than half a degree.

The argumentation has, imo, a certain logic, but only applies to air-water heat pumps, at most also to flat collectors. The brine temperature in deep drilling shouldn't have a daily cycle, or am I overlooking something?

A gas heating system doesn't have one either, and yet people reduce the temperature. Because the heat demand of the residents is lower.

But I don't feel like arguing this point further, as it is not my own. I read this recently and the idea is quite understandable. The question remains which way is really more efficient; there are arguments for both.

Night setback is taken into account in the heat protection verification and can make it appear better, I just thought of that.

A gas heating system doesn't have that either and yet people lower the temperature. Because the residents' heat demand is lower.

I would like a factual argument. "people lower the temperature" is not an argument but an unconfirmed statement without any content. By the way, I used to not lower the temperature in my apartment with gas heating (and compared the consumption with "lowering," and there was no difference, taking the outside temperature into account)

But I don't feel like arguing this point any further

It would be nice if you start by arguing first!

Night setback is effective in old buildings that are very poorly insulated and do not have underfloor heating. Then 2-3 degrees less inside results in energy savings through a smaller temperature difference and thus lower heat flow to the outside. Reheating is then somewhat less bad because the goal is to raise the air temperature and not to heat the screed warm (overall somewhat less comfortable—if the building itself is warm, you feel comfortable at a lower air temperature than in a cold building). Moreover, gas heaters operate more efficiently when they are warmed up, so they can run longer cycles! You cannot simply transfer this completely different concept to a modern, insulated building with different technology (or rather: you can, but it is wrong).