Room thermostat + temperature + floor temp + dew point sensors?

Hardware
1

Hi! I am building a new home and I am about to order installation of floor heating (water based, connected to NIBE heat pump). Each room will have its own loop with electric valves connected to Shelly DIN relays (so opening/closing will be controlled by HA). Each room will need a wall thermostat, temp sensor, floor temp sensor and floor dew sensor (for reverse-loop mode for cooling in summer). I don’t want “dumb” (and ugly) thermostat knobs so the idea is like this:

  • Some sort of 4" touch screen - Like Shelly Wall Display or Sonoff NS Panel Pro (side-loaded FullKiosk mode for HA) // This provides the Thermostat control (+ some extra dashboard functions)
  • Shelly 1 Gen3 + Shelly Plus Add-On + DS18B20 // This provides the Floor temperature sensor (to be used to avoid overheating the floor)

I don’t have a real use for the Shelly relay (no light connected to it) but unless I am wrong the AddOn can’t run on its own (no wifi) and can not be connected to the touch panels. On the other hand it will give me some future opportunity to use if i ever need one. Two questions:

  • Is the above solution OK? Yes, the relay is unused but I haven’t found prebuilt solution for DS18B20 which would fit behind the panel inside installation box. I am a bit under time pressure so i can’t DYI something so I prefer “plug and play” solution (connect the cables, connect to wifi/ZHA and done…)
  • What floor dew point sensor should i use and “how”? I need that to avoid cold water in the loop going “too cold” (in reverse/cooling mode) as it would cause dew/moisture. Also it would be excellent if i could use it with the Shelly AddOn (even though the support page does not say anything about such device support)

Thank you in advance for any help/suggestions !

2

It’s ok, another option could be Shelly Uni or DIY Esphome board.

Is it really necessary? It’s not easy to setup humidity sensor probe to reliably measure floor slab humidity. Can’t you just estimate it from temperatures?

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What a tiny little F… well reading the specs it even has a wifi module so is this a full replacement of the Sheely relay and the AddOn!? If so then this is awesome for its price (as i will need 6 of them huh). I will still need a 12-24 little power source but that is not an issue as i can buy these small 12V/6W/0,5A ones which fits the one-gang box (I’ll have the deep ones) for ~5 bucks each…

To be honest I am now questioning that as well. I found some discussions about NIBE and people are just stating “it works” w/o any explicit details that they had to install these. I just sent an email to the contractor asking if this is required or not…

Oh and thanks for quick reply. The Shelly Uni will reduce the cost a lot :slight_smile:

4

Shelly Uni is still totally “waisted” to just measure DS18B20, it’s designed to be used when output/input voltage/currents are not compatible with normal Esp32 devboards.
In you case Esp32 devboard and temp sensor could do the job with total cost about $5.

If you want to measure RH of your floor slab, it needs to be in close contact with it. So pushing a RH probe in PVC conduit designed to measure temperature doesn’t really work. You can estimate risk of condensation just by measuring slab temp and inside temp. Or floor surface RH.

1 Like
5

Got it … added this to my “maybe one day i will try to do…” list :slight_smile: