Hello Michi,
in these ceiling elements, the pipe system is located behind a brick shell in the concrete core.
Whether the system is suitable for the respective construction project or not can be determined based on the test values and the required heating load per room (DIN EN 12831; despite all criticism) as well as the design (VDI 6030). By the way, VDI 6030 represents the state of the art and thus the required performance, making the determination of heating values per sqm of room according to DIN EN 12831 mandatory. In fact, no house should have been built without these proofs for a long time.
The specified system achieved a heating output of max. 49 W/sqm in the test with a pipe grid of 18.5/9.5/9.5. The conventionally offered system has a tested output of 45 W/sqm (r=250mm). The response time ranges from 120 min to 650 min (turn-on/turn-off depending on the chosen system), which is slower than a modern underfloor heating system.
ATTENTION THIS IS NOT THE ACTUAL HEATING OUTPUT!
Experience in our own house:
Because the system was tested
without plaster. However, this is completely unrealistic in practice. I do not know any house with a "bare brick ceiling". Based on comparable measurements of other systems, the plaster reduces the output by another 25-30%. Consequently, the response time also becomes somewhat worse. So, when designing, some "reserve" should be planned since the
real HEATING OUTPUT is hardly more than 30-35 W/sqm.
In my KfW 40 house, the supply/return temperature when only the cores in the 250 mm grid are activated is about 45°C to 42°C (outside minus 16°C). When simultaneously using a tiled stove and an additional heat source in the bathroom, this is sufficient.
I can’t really say much about the "18.5/9.5/9.5" grid system because we ultimately decided on a different manufacturer back then. However, the difference between the 250 mm and the "18.5/9.5/9.5" grid system is only about 4 W/sqm, which is rather insignificant.
The system we chose is heated in two circuits. That means the cores and a second system located directly at the surface.
When both pipe systems run simultaneously (=buffer and heating in the ceiling), the supply/return temperature at outside minus 16°C can be lowered to 27°C to 24°C. Ideal for our air heat pump.
A tip from painful personal experience:
Only if I have precisely defined the performance beforehand can I demand it. Or in other words: If I buy "a piece" of a car, I cannot complain if it only has 30 hp. Especially if that is also stated in the papers.
So
1.) Determine the heating load (DIN EN 12831, even if there is criticism of the procedure)
2.) Demand from the manufacturer a design according to VDI 6030, paying attention to supply/return. These should also match the energy certificate in proportion. However, they are not transferable 1:1 due to different data bases and calculation methods.
3.) Have the manufacturer guarantee a norm-compliant heating of the property with regard to energy-saving regulations, DIN and VDI.
I hope all this does not confuse more than help.
Best regards
P_B
Ps.: The 15,000 euro seem very high to me. But this probably depends on the heat pump. Our builder originally wanted that too. In the end, it was almost 8,000 €.
Hello,
the ceiling elements contain a pipe system through which heating can be done in winter and cooling in summer. The underfloor heating would then be omitted. Does anyone know the system and are there disadvantages to ceiling heating compared to underfloor heating?
Initial reviews suggest that the requirements for a heat pump with groundwater or geothermal probe are met. Heat pump manufacturers advertise "natural cooling" or "free cooling." The heating water is supposed to be cooled without the heat pump running.
The additional costs for the heat pump, development of the heat source and ceiling amount to approx. €15,000 compared to gas condensing technology. Since there is no heat pump tariff for the property, the saving with the heat pump will probably amount to only around €500 per year.
Best regards,
frank