Is optimization of the heating system possible after hydraulic balancing?

Hi everyone!

I'm coming across topics in which I have built very little knowledge so far but now have to deal with.
Basically: we have an air-to-water heat pump (Tecalor THZ 504) and underfloor heating.
Our heating installer performed a "hydraulic balancing" before handing over the house, there are documents about it and it was apparently relevant for the KFW.
Therefore, the sanitary advisor once told us that we should actually not / may not change anything on the heating system ourselves (?), because that was the basis for the KFW subsidy.

Now we do live in this house, however, and in practice we have a few minor issues with the heating.
Overall, during the cold months, the temperature in the house was pleasant. Since spring is coming, it's slightly too warm for me inside. As far as I know, you have to adjust the "curve" a bit here. Simply lowering the temperature would probably not make sense because the heat pump controls the room temperature based on the outdoor temperature, and since it was okay in winter, I assume something in that relation is not right. If I lower the temperature myself now, then I would have to turn it up again when it gets colder, which somehow doesn’t seem sensible to me.

Furthermore, the bathroom upstairs is constantly too cold (significantly), and the bedroom is too warm (a bit).
This is related to the fact that we always turn the room thermostats fully on according to agreement with the heating installer (anything else would be a waste of energy, we were also told here in the forum), plus the things would keep clicking otherwise, which is annoying (especially at night). In the bathroom, even fully turned up, simply not enough heat arrives for my feeling. In the bedroom, it quickly gets too warm, we prefer to sleep rather cool anyway.

Is there a way to adjust this so that the bathroom gets warmer and the bedroom no longer gets so warm, without turning down the thermostats? Like changing the distribution?
And are we allowed to do that even though the hydraulic balancing was carried out? (I don't really know what that means).
I also found in the documentation I received recently a planning note from the executing company for the underfloor heating stating "reduced output" for the bathroom of 49W, requiring additional heating surfaces. :/ However, we do not have those. During the selection process, we sorted out the towel radiator, with the reasoning that it wouldn't get really warm anyway with often below 30°C supply temperature.
What we didn’t consider and know at the time was that it probably would have helped us to heat the bathroom overall higher.

Quick note:
Thermal balancing, Google it.
More tomorrow

If it is getting too warm for you at the moment, you need to check whether your heating system offers a parallel shift, which simply means that all values are shifted up or down by, for example, 1 degree.

Is the heating still running at the current temperatures?

For the bathroom, one would have to see what the flow rate is and with what flow temperature is being worked, the same applies to the bedroom.

It may be possible to make adjustments there by regulating the heating circuit distributors.

Here, ALL facets of the thermal balancing are examined from all sides.

https://www.hausbau-forum.de/threads/broetje-blw-neo-8-heizkurve-einstellungen.36659/

The underperformance of 49W already suggests to me that a room-specific heating load was calculated. Can you scan and upload the data? If everything was calculated at 21°C and you then have an undercoverage, that would be a challenge. But it could also simply be that other heating circuits, e.g. sleeping, can be throttled and then more performance could fall to the bathroom.

Next winter thermal balancing. Now it’s no use anymore. I would also set the thermostat in the sleeping area to the desired temperature if it’s too warm.

If the heating curve is now lowered by parallel shifting, there is a risk that it will become too cold in the rooms during winter. If it is comfortable in winter but too warm during the transitional period, the heating curve will likely be too flat and you will need to make it slightly steeper. How that works with your [THZ]? It should be in the manual. Possibly, the bathroom could get a bit more flow and the bedroom less. However, more information is needed for that. Heating circuit lengths and current flow. Also, the question of which rooms border the bathroom and whether they are also heated.

If it’s getting too warm for you at the moment, you should check if your heating system offers a parallel shift, which only means that all values are shifted up or down by, for example, 1 degree.

Is the heating still running at the current temperatures at all?

For the bathroom, you would have to see what the flow rate is and which supply temperature is being used, same for the bedroom.

It might be possible to make adjustments there by regulating the heating circuit distributors.

Shifting the entire temperature would not be a problem; the problem is rather that it would then be too cold in winter. It’s only the transitional period that is too warm.
The heating still runs occasionally. It was on summer mode not long ago, but it’s a bit cooler here right now, so it’s on again.
Here is a screenshot of the current supply temperature/settings. We only have one heating circuit; the values of the second one can be ignored.

We recently received a huge package of planning and execution documents for storage, which also includes many documentation sheets from the company that installed the underfloor heating.
For the bathroom, there are two such distribution devices (the only room like this on the upper floor). For the bathroom, it states 1.8 and 1.7 L/min. For the bedroom, 0.8 L/min. I think the supply temperature should be the one from the screenshot (?). If I understand it correctly, since there is only one heating circuit.

The reduced output of 49W already suggests to me that a room-by-room heating load was calculated. Can you scan and upload the data? If everything was calculated for 21°C and you then have an undercoverage, that would be a challenge. But it might also just be that other heating circuits like the bedroom can be throttled, and then more output could go to the bathroom.

Thermal balancing next winter. It’s no use now. I would also set the thermostat in the bedroom to the desired temperature if it’s too warm.

Thank you very much for the link, I will study it.
Yes, the heating load was calculated room by room. In the doc, the bathroom was calculated at 24°C, the utility room at 18°C, all else at 20°C.
But I don’t know how that is supposed to be achieved, since we set only one temperature at the heat pump (currently set to 20°C).
Turning the thermostat down is not my preferred choice. Several people have told me that it’s a waste of energy, but more importantly: The constant clicking at night annoys me.
I was also hoping that maybe we could redirect some heat from the bedroom to the bathroom – if that’s even possible. I’m a layperson and the system is quite complex.

If the heating curve is lowered by a parallel shift now, there is a risk that it will then be too cold in the rooms in winter. If it’s comfortable in winter but too warm in the transition period, the heating curve will probably be too flat and you have to make it a bit steeper. How to do that with your THZ? It should be in the manual.
Possibly the bathroom can get a bit more flow and the bedroom less. But for that, more info is needed now. Lengths of heating circuits and current flow rates. Also the question which rooms border on the bathroom and whether they are also heated.

I found how to adjust the heating curve. However, I wouldn’t know what to set there. There are quite a few individual values that don’t mean anything to me yet.
Only the guest room borders the bathroom, and it is also heated like all rooms. Apart from the utility room and bathroom, all are set to 20°C – what the heat pump maintains as the set temperature for 20°C is in reality closer to 23°C according to the thermometer – but that’s totally fine for us; we like it a bit warmer.
Heating circuit length in the bathroom 83.7m and 75.3m. In the bedroom 107.1m.

I can scan a few pages of the doc for you if you tell me which ones, there are quite a lot. :D