I am looking for a subtle thermostat. Currently my thermostat is at the right place, but the device in use is dumb (no way of talking to the device remotely), and one needs to operate it using the buttons and looking at the screen to control the heating in the house.
Ideally I get right of this device, I want to have a larger tablet in the living room, from which I want to control the room temperature. There is no need for the tablet and the extra thermostat screen.
I am thinking of putting wireless thermometers in each room, so there is no need to have a thermometer included in the small subtle thermostat, I think it just needs to be able to tell my boiler to start heating the house if HA tells it to (or maybe it is wise to have a back up in case HA is down).
Don’t forget that many motion sensors include temperature sensors. I have Philips Hue, which reads light levels as well - you could kill several birds with one stone.
If you have an opentherm heater, i would recommend buying a simple honeywell round modulation. Then place an opentherm gateway (https://otgw.tclcode.com/) in between the thermostat and the heater to make it smart.
Ok! Great! I will be looking into this, do you also have a hint how to control the room temperature for different rooms? Would you go the route with smart valves (particular brand in mind?), or something else?
My house is very well isolated, therefore i’ve no use-case and limited knowlgede about smart valves. Whatever you choose, make sure that there is local control possible in home assistant (ideally local push).
Those systems can be very expensive, and you either need to take care of batteries or connect cables. I would consider if those costs and hassle is worth it. For something as crucial as heating, i’m inclined to say: keep it simple.
Please be aware that various “smart” thermostats are very dumb and behave like on/off thermostats (even some that work via opentherm). It’s important that they modulate, and that they modulate well. This is very important for economical and comfort reasons. For example, most (all??) Nest thermostats do not modulate in practice, despite the fact that some of them support the opentherm protocol.
All those reasons above, were decision factors for me to go for an old-fashioned honeywell thermostat: they are reliable, and modulate very well. Combined with the opentherm gateway, you get best of both worlds. Even if the opentherm gateway would crash completely or break in pieces, the thermostat would still be communicating to your heater (fallback mechanism).
I’ve read too many examples of either dumb non-modulating smart thermostats (Nest), cloud-dependencies leading to multiple cold evenings per year (can’t remember the name), and/or too much hassle with charging batteries.
But all in all, each use-case is unique. As long as you can make a good decision in which you can weigh all the pro’s and con’s.
I’d say: a dedicated heating system is well worth the investment. A good Opentherm thermostat that communicates with it’s smart valves, like Tado or Honeywell Evohome, is way to go.
Those systems are way more sophisticated than simply turn the heater on if the temperature is to low, and off if the temperature is fine. A good system adjusts the level of heating to the need of the respective rooms, and predicts when to stop to prevent “overshoot” because the heater will continue to heat the room after the heating is turned off. So the initial cost is earned back soon enough by saving money for years on end and saving the climate in the process.
A system that can change the setpoint is an ok second best, as long as the thermostat stays opentherm. But avoid a too simple on/off system based on your own thermometer readings at all cost. You’ll pay for that with gas.
I’ve heard good stories about Honeywell Evohome, but integration with home assistant seems far from ideal Honeywell Total Connect Comfort (Europe) - Home Assistant : cloud polling, which is the lowest grade (local push > local pull > cloud push > cloud poll). But perhaps another way of integrating it exists?
I use Tado and I’m happy with it, but it is indeed cloud polling. When without internet, its function is limited. If you connect it trough Homekit you’ll have local control, but more limited Home Assistant functionality. I’m happy with Tado, but the cloud part is indeed a downside. I accepted it because of the homekit fallback option. I got it cheap and Evohome is expensive.
Plugwise may also be a good option if it is sold where you live, I didn’t look into that as it wasn’t on my radar back then but it does do true zone heating, and is local. I think I might have chosen that in retrospect.
My home is from 2010, it’s quite good isolated. Apart from the living room, i hardly ever heat the other rooms. So in my case, smart radiator plugs were never a serious consideration.
The ideal solution would have the following characteristics:
-no cloud dependency at all
-local push
-cheap
-good and efficient modulating
-opentherm compatible
-robust
-user friendly
-unobtrusive looks
-can heat each room individualy
The opentherm gateway fulfills all of those criteria with flying colors (when coupled with a good thermostat like the Honeywell Round Modulation), except for “heat each room individualy”. So i think it really comes down to the following question: how important is this feature for you?
If that feature is important to you, you will most likely loose on multiple of the other criteria. I have not seen any solution yet that checks all boxes.
But Plugwise does claim zone heating, so the last box you miss should be ticked as well? https://www.plugwise.com/zone-control/?lang=en
Cheap is a relative term, but it is definitely worth the price.
I have no clue how good/efficient Plugwise is in actually modulating properly in practice (instead of “on paper”). Reason for mentioning this, is that i have read mixed comments from users using other smart-home brands about this topic. Modulating is an expertise that has been developed and mastered by the traditional heating companies over the years. If Plugwise can match that level of refinement, it could very well be a good option.
Apart from this, Plugwise is local pull, not local push. But that can be acceptable.
Regarding robustness of the system: i have no idea. Long-term users mights give some insights about this? For example: what would happen if wifi is down? What would happen if zigbee is down? How stable is the firmware? What would happen after coming back from a power cut? Etc. Opentherm gateway is rock-solid because of the fallback mechanism (it will then passively pass-through the raw thermostat values). I am very interested to hear the experience of long-term Plugwise users in that regard.
I agree with the list provided by @pimw . Now I only need to let my radiators communicate with my HA. Plugwise looks very promising, but it doesn’t have the analog option. I still want to be able to control my heating valves, when wifi is down for example.
So that is also a reason why i don’t want it to communicate w/ the cloud, if the cloud is down, that means no heating.
