ᐅ Thermal Curtains – Do They Really Work? – Who Has Experience?

Knallkörper schrieb:
Please do not try to deliberately misunderstand my posts. When I say "the circuit is closed," I am fully aware that the screed continues to release its residual heat for a long time.

My point is that with ERR, I can "turn off" a room for an extended period. At that point, the heating curve and balancing no longer matter.

You can also simply close the heating circuit without ERR. However, the hydraulic balancing will still be disrupted... If you change something in a system with, for example, 20 heating circuits at 3, the system will logically no longer be in an optimal state afterward.

In your example: the upper rooms are still being heated, even though there is less heating surface available. This means you need a higher flow temperature than if all heating circuits were open → loss of efficiency.

Who says that ERR actually helps achieve a greater or smaller temperature difference between rooms? I don’t have ERR, but of course, my bathroom is warmer than my bedroom (within limits, of course). That’s how my system is set up... ERR only makes sense if you have a heating system that can change temperatures quickly, meaning a system with radiators and a high flow temperature.

Tego12 schrieb:
Who actually says that using ERR results in more or less temperature difference between rooms?

I am a proponent of this because there is still a noticeable difference between “heating a little” (through hydraulic balancing) and “not heating at all” (with ERR off). In the short term, meaning hours, it doesn’t really make much difference, but over days it certainly does.

Let me elaborate further. As you know, the difference between a control system and a regulation system is that regulation responds to external disturbances. In this sense, the essentially fixed setting that you adjust hydraulically is a control, but ERR is a regulation. That’s the theory; now to my practical issue:

At first, I also deactivated my ERR and adjusted temperature differences between rooms via hydraulic balancing. However, I have a 15-meter (49-foot) long facade facing directly south, and correspondingly one that faces directly north. In winter, solar gains on the south side provide enough heating energy to exceed the desired room temperature. This is the external disturbance that ERR can respond to. If I rely only on hydraulic balancing, heating will still continue because the outdoor temperature sets a corresponding supply temperature, which may be necessary for the north side. When I also use ERR, in my case about 7 to 8 heating circuits switch off, even for days during sunny winter weather. That brings us back to the purpose and function of a regulation system.

Tego12 schrieb:
If you change 3 out of, for example, 20 heating circuits in a system, then the system logically is no longer in an optimal state.

That is not quite correct if by “system” you mean the hydraulics. Hydraulic balancing is not disturbed when using a delta-P circulation pump. I believe all modern circulation pumps now use delta-P control.

Of course, I have also performed hydraulic balancing and optimized my supply temperature; only my settings may run a bit “fatter.” I have about 3 Kelvin (5°F) higher supply temperature than necessary so that my bathroom floor stays comfortably warm even when the window is open. If energy prices are no longer as low as they are today, I will reduce this by 3 Kelvin (5°F) — but I will still need ERR on the south side during sunlight.

Knallkörper schrieb:

However, I have a 15-meter (49 feet) long facade that faces directly south, and correspondingly one that faces exactly north. In winter, I get enough heating output from solar gains on the south side to exceed the desired room temperature. This is the external disturbance that the ERR can respond to. If I rely solely on the hydraulic balancing, heating will still continue because the outdoor temperature dictates the supply temperature, which may still be necessary for the north side. When I additionally use ERR, a total of 7 to 8 heating circuits are switched off, sometimes for several days during sunny winter weather. This brings us back to the purpose and function of the control system.

I have a similar "issue." I don’t have individual room control, but I do have a control unit in the living room (similar to your setup, with very high solar gains due to large windows). The heating control is therefore not based solely on outdoor temperature but is a combination of outdoor and indoor temperatures. What this does not affect, however, is the hydraulics of the underfloor heating, since individual heating circuits are not adjusted; instead, the heat pump generally supplies less or even no energy to the house. The solar gains distribute more or less throughout the entire house anyway, at least in well-insulated buildings.

Another important point: I use passive cooling through the geothermal heat pump, which activates automatically once a certain temperature threshold is reached. It must be ensured that enough heating circuits remain open... without ERR, no special control is needed for this and nothing can go wrong. Especially in rooms with strong solar gains, a little heat is continuously removed here, and the temperature settles slightly lower without significant cost.

Knallkörper schrieb:

Of course, I also performed hydraulic balancing and optimized my supply temperature; only my settings might be "a bit stronger." I have a supply temperature about 3 Kelvin (5.4°F) higher than "necessary" so that I always have warm feet in the bathroom, even when the window is open. If energy prices are no longer as low as today, I will reduce that by 3 Kelvin—but I will still need the ERR on the south side when there is sunshine.

If efficiency is not a priority and someone has no interest in sustainability (without any judgment), then there is no need to optimize the heating system, let alone use thermal curtains. Of course, everyone can handle this as they wish. From a purely financial standpoint, we are not talking about figures that would significantly impact anyone who can afford a house. The time some people (including myself) spend optimizing their heating could certainly be used more effectively elsewhere... Let’s just call it a hobby.

Okay, so in the end, you also have a system that prevents continued heating when there is sunlight – with the added comfort benefit of possible cooling, which I almost envy. Your system in my house would have the disadvantage for me that the bathroom heating (north side) switches off when the living room (south side) gets too warm. For me, the bathroom never gets "too warm."

"My" system is also efficient to some extent – simply turning off under certain conditions is still better than when energy input continues solely controlled by the hydraulic balancing. Still, I am purely focused on comfort here, that’s true, but with my energy source (gas combined heat and power unit) I don’t benefit from having the lowest possible supply temperature.

Conclusion: The design or evaluation of heating control often does not work according to a fixed formula.