Brötje BWL Neo 8 - Problems with the setting

At temperatures around 10⁰C, the pump cycles like crazy instead of reducing its power.

Yes, I can believe that. The heat pump is too big and can’t modulate down far enough. The lowest output is already way too high for your house.

The heating engineer says, "That’s normal."

Yes, because he installed a heat pump that is too large. A smaller one would still cycle a bit. But at 10 degrees, maybe only 3-5 cycles a day, if at all.

Have you had a room-by-room heating load calculation done with your desired temperatures? Otherwise, the heat pump can’t be properly sized.

But I fear the heating engineer installs according to the motto "I’ve always done it this way" and "My goal is achieved as soon as the place is warm—no matter how."

Currently, it should look more like this:

Those are two cycles at currently 8 degrees. Cycle 1 from 1:00 to 6:30 am (the peaks are defrosting; the Panasonic necessarily uses the electric heating rod then), cycle 2 is from 11 to 13:30.
Between 7 and 8 am hot water, the remaining peaks come from the electric car and after 11:30 am from the washing machine.

The system was also put into operation by a Brötje technician.

Then take him along as well. Even if it might cost a little money. But what the heating engineer says is nonsense.

Then include him as well. Even if it might cost a little money. But what the heating engineer says is nonsense.

Yes, that is what I intend to do now. I already know that the heating engineer is talking nonsense. We do not have a room-by-room heating load calculation, only one from the energy consultant. The energy certificate states that the maximum heating load (with hot water) is 5.8 kW. Just now I found out that the Brötje can modulate down to about 2.5 kW. If mine were to do that, the cycling would definitely lengthen. But mine ALWAYS runs at almost 7 kW and does not want to go down. Is there something to consider in the settings? Here is a diagram from today.

The heating engineer says that because of the warranty, he has to adhere to the manufacturer's specifications...

Yes, but Brötje also allows operation without a buffer tank, provided, for example, that ERR is omitted. And honestly? If the heat pump keeps running like this and breaks down in two years, no one will take the warranty anyway, because then they will probably say: oversized, operated incorrectly. At least that is what I would expect in case of doubt.

We don’t have a room-by-room heating load calculation, only one from the energy consultant. The energy certificate states that the maximum heating load (with DHW) is 5.8 kW.

Then a heat pump with a maximum of 5 kW should be chosen and not such a large heat pump as you have. But as said, a proper room-by-room heating load calculation should be performed (MUST, if the heating engineer does his job properly). With the calculation (including the room temperature you want) the underfloor heating is designed (installation spacing, pipe dimensions, length of circuits) and the hydraulic balancing is calculated. Just ask the heating engineer for the calculations for fun.

Is there anything to consider in the settings here?

Sorry, I have no experience with the device so far. Therefore, I cannot advise on the settings. Sorry

HAAAALLLLOOOO :-)

your heat pump is certainly oversized and there are better ones nowadays. Nevertheless, you have a good one here ;-)
It modulates both the flow rate and the power!

Which mixer is installed? Please provide a photo if possible.
A pretty big energy consumer, which also repeatedly interrupts the heating cycle, is the hot water preparation. I do it once a day directly after the utility company lockout and only up to a maximum of 45°C. That way, the heating cycles can run through from start to finish.
Important to know: The Brötje "buffer tank 100L" is actually a hydraulic separator!

Here are the first measures:

1. Set all ERR (thermostats) on the walls to the highest level.
2. Main menu --> User level --> Code 0112
3. Heating circuit --> Parameters --> Mixer setpoint to "No"
4. Heating circuit --> Heating curve (which heating limit is set?) to 20/25/27
5. Hot water preparation --> Set to once a day, if possible directly after the utility company lockout
6. Deactivate the night setback

Good thing you got in touch.
We're going on vacation for 2 weeks tomorrow. I think I'll only start with the adjustments in January. I hope you'll help me with that. Unfortunately, my heating guy is totally unreliable.

I know the pump is oversized. But I can't change that now and have to make the best of it.
Please write to me for now, to what extent your pump modulates the power? For example, today, with the warmer temperatures. At how many kW is it running for you? How often does it switch off? Mine cycles like crazy and always runs at about 7kW.
We have the domestic hot water preparation under control. It switches on once a day, heats up to 47⁰C and that's fine. That is enough for us too. Domestic hot water consumption about 37kWh electricity

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Here is a screenshot from today