Integral device Stibel Eltron LWZ 504 with central supply air

That doesn't mean anything to me, I'm not very tech-savvy

: The 304 can cool as well, right? At least that's what the website says. Or did you not want to use that? Especially since it's too warm for you, that would be a good thing.

Sort of, only the Sol can do that, but we have the other version because we don't use solar support and therefore didn't justify the high extra cost.

But the cooling function of the heat pumps only works through the underfloor heating. I somehow imagine that being quite uncomfortable in summer with bare feet on the cooled floor?

I will report later how it feels. When heating, the underfloor heating was not even slightly warm, which almost disappointed me a bit since I always have cold feet. I had thought it would be really warm. However, then you probably wouldn’t be able to stand being in the house either, since it is already quite warm and pleasant (as mentioned because of the insulation). Let’s see how it will be with the cooling. Since I find that particularly important in the bedroom and I hardly ever walk barefoot in the house anyway, a slightly cool floor would not bother me.

Hello Daniela,

were any additional components installed for the cooling function of the system?

Regards
D.Gerner

Hello D.Gerner,
there are different ways to cool with the LWZ 504. For space reasons, we did not want to set up an extra buffer tank, so we needed the following components or followed the following specifications (I am giving it as I understood it back then, so without guarantee):

- An FES (227664 FES Komfort) must be installed in the area to be cooled

- Minimum floor heating area over 40 sqm

- Volume flow of 700 liters per hour

- Valves on the heating circuit distributor must be openable (openable and coolable even in summer)

- Composite pipe system 16 x 2 mm/laying distance 10 cm or even better 20 x 2.25 mm/laying distance 15 cm

They also installed such a bypass thing in the LWZ for us, as I was told. But I cannot say exactly how it all works and cooperates. You definitely have to be careful and make sure that no dew/condensation occurs in the floor during cooling and that no moisture results there, but that actually should/must not happen. We will pay attention to this and I will report more soon.

Best regards
Daniela

Thank you for your experience/contribution