ᐅ Is it worth installing a smart system with a slow-responding underfloor heating?

Hello everyone,

In our new KfW70 energy-efficient house, a Vaillant gas condensing boiler is installed. There is a solar collector on the roof. Underfloor heating is installed in the living areas. I am now considering either buying the “smart” modules directly from Vaillant or opting for a third-party solution. My idea is to save energy costs by using smart controls—that is, adjusting the heating output according to demand, for example, reducing it during daytime absences.

I have read online that underfloor heating systems are relatively slow to respond. Even the German Association for Underfloor Heating apparently recommends turning the underfloor heating on in autumn and running it continuously until spring.

One of the main functions of smart heating controls is to adjust the heating output based on demand (for example, lowering it during daytime absence at work), right? If underfloor heating is so slow to respond, does smart control even make sense?

Thanks for your assessment!

In my opinion, no. The heating turns on automatically based on the outside temperatures (of course, everything depends on the heating settings) and turns off again when it’s warm enough (i.e., autumn/winter/spring). I think, for example, that our heating will turn off next weekend because it’s going to be very warm here (in the west). Save your money and buy yourself something nicer.

I haven’t touched the controls in two years (not even in the old house over 10 years!).

Hello,
a simple, slight temperature reduction during the day should actually be possible with any heating system that already has a built-in controller. You just won’t be able to do it via an app on your phone, but you can set it directly on the heater. It should have several timer programs built in.

However, this doesn’t make a big difference. On the one hand, a modern house hardly cools down at all, and the underfloor heating system is also quite slow to respond.

Best regards,

Andreas

With constant adjustments up and down in such a slow system, you don’t save any energy. During the 6–10 hours of absence and setback, absolutely NOTHING happens. The heating system is smart enough; everything is professionally configured once and at most adjusted again to your specific needs... from that point on, I wouldn’t touch the controllers or anything else. That is the only way to operate underfloor heating economically and efficiently.

@Everyone: Many thanks for your quick responses. The consensus on this question is really VERY clear (which is not always the case with construction-related topics 😉). I will skip the "smart" additional features (which would have cost me about €1,200 using Vaillant products, by the way...).