In my house I have 3 circuits of floor heating elements, each is connected to single phase (230V) 16A fuse and on one of them I have Heatit Z-TRM3 connected via z-wave to my home assistant. Others are manually controlled dumb thermostats.
That thing works, but at least the particular one I got causes a lot of interference to the z-wave network, so I’m a bit hesistant to add any more of those.
Features I must have:
- Option for a floor temperature sensor. Each thermostat has separate pipe going to the floor and the floor sensor is easy enough to replace, but it is a must have option
- Air temperature sensor. 2/3 of the heating elements are in a concrete slab and that means that measured temperature of the slab very slowly affects the air temperature, so I need both. ESP32 or equivalent as a separate sensor might be a decent workaround, but I’d rather have both on a single unit.
- Obviously the 230V 16A capability as that’s what they’re wired on and even if I don’t have 3kW elements on the floor it’s what’s needed to meet the code
- Manual controls on the device itself. Should my raspberry pi running home assistant kick the bucket or some other major issue with the automations happens, I still need an option to control the device. And that’s a strict requirement, no bluetooth apps on the phone or anything, I must have manual buttons or some other way to control the thing without home assistant or any other smart device.
- And addition to previous one: No cloud requirement. Allowing the device to the internet for a setup is fine, but in the long run it must be happy in a isolated network without internet connectivity
For the communication I don’t really care. I currently have only wifi/z-wave as an option, but if there’s something on zigbee which ticks all the boxes I can invest in a usb-dongle or a hub.
Price is obviously a concern, but it’s hard to set any strict boundaries. I won’t throw a 1000€ for a thermostat, but anything even remotely reasonable goes.
What are your suggestions for a situation like this?
I have a feeling that finding a smart thermostat with this kind of load capacity, on three separate circuits no less, is going to be a tall order. Are you savvy enough that you could wire up a system that uses a regular thermostat to control your floor heating via relays or contactors?
I think here’s some misunderstanding going on. I want 3 separate thermostats which each control their own circuit, as they are now, not a single thermostat which could in itself control each of the 3 phases. Thermostats are on different rooms (and even floors), so I need different measuring points as well.
But, as the floor heating has very slow impact on actual room temperature, I want (and need) the option that the resistive wire on the floor doesn’t get too hot, but it still has an input from the actual air temperature on the room, so the thermostat can adjust that as needed.
The Z-TRM3 ticks all the boxes on paper, but it’s causing problems on the Z-wave network itself, so I’m not too interested to add any more of those to the system. Also with that there’s option to just turn it off via z-wave and I haven’t found a simple way to re-enable the heating from the thermostat itself, so while it gets the job done it’s not optimal solution.