Air-to-water heat pump - Nest Thermostat

How gracious

To give you one more thought for the night and simply reverse your own statements:

Your ever-popular solar gains - according to you, without ERR lead to overheating. That is complete nonsense, because with ERR the room is throttled, it heats up. The underfloor heating does not transport anything here, but, exaggeratedly speaking, continues to heat up.

Without ERR with the corresponding hydraulic balancing, the system dissipates the heat and distributes it to the overall system. And don’t you dare say now that the whole house overheats – no one produces that many solar gains here during the heating phase.
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But I’m just a stupid IT guy who simply has nothing to oppose a physicist. At least I know how to use quotes correctly .

I can’t help it – here is an argument that says EXACTLY the opposite of your previous one! An IT guy should see that; you have enough logic from your studies :P
On the one hand you say the underfloor heating is too sluggish to react to such short-term things, now you say the underfloor heating distributes the otherwise introduced heat in the overall system. That contradicts itself 100%.
The only thing that can react to short-term energy inputs is an EER, since the underfloor heating itself is too sluggish.
A properly adjusted heating system with EER doesn’t throttle one or more rooms, but blocks excessive short-term energy input so that overall, exactly the right amount is heated, not too much, and corrects the only disadvantage of underfloor heating, its sluggishness.

Forget it - they are just individual opinions that mean nothing. Likewise practical examples - all nonsense.

But luckily my heating engineer said exactly the same arguments - without me having to ask him. That’s how I knew I got a good one .

Saruss will surely come along soon with the meaningfulness of a 1000l buffer tank...

Very good, factual arguments.

Come on, just leave it... you simply haven't understood the principle...

Come on, just stop it... you simply don't understand the principle...

Can't you just stop? This stubborn general claiming, sweeping statements are not convincing. Personal attacks neither.

Now I’ve also become suspicious and interested. We have ERR everywhere in all rooms in the house and I’m now wondering whether we should even use them, or not?! But the arguments "against ERR" haven’t fully convinced me yet. If I take the example with the sun and WITHOUT ERR, that would mean the following: The sun heats the room air. The room air, in turn, then heats the screed and the underfloor heating? (The question would be how long does that take? People always say underfloor heating takes about 1-2 days to heat a room, it would be the other way around as well, right?) If then the water of the underfloor heating in this room is warmer and constantly circulates, also in the other rooms and eventually reaches the return flow of the heating system, then the heat pump knows that it has to use less energy? But I still ask myself how long something like that takes? It can’t provide a short-term relief from the "heat" in the room, can it? Or have I completely misunderstood this? I would appreciate some "enlightenment"

How do you regulate areas without ERR where changing temperatures are desired.

An example for me would be guest or work rooms. In normal operation (95% of the year), a slight heating to 15-16° is sufficient. If I have guests or want to use the room occasionally, it should perhaps be 20° then.

Temperature in the children's room:
Nice weather - child plays outside - low temperature
Bad weather - child plays inside - higher temperature
With the ERR I can influence this. Without it, I would heat the room to 20° every day and send the heat outside at night when ventilating.