Homey as a thermostat for the whole house


Currently I live in an appartment with collective heating. I have a few thermostatic radiator valves and I can now simply use Homey to make heating schedules per room. I am going to move to a house with a central heating unit, which of course has a thermostat in the livingroom that controls the temperature there.

I was wondering if there is any way to have Homey take over that function. So that Homey sends messages to the central heating unit. Suppose the central heating unit works with OpenTherm, or whatever technology is available, what would be my options?

The idea is that Homey can tell the central heating unit to start warming and pumping when one of the rooms requires heat (so not only the livingroom). (it would be even better if it can even throttle it from a environment/cost savings point of view)

You can if you replace your thermostat : I use ecobee, but nest and honeywell are also options.


I then have ecobee sensors in each room of the house which allow for the heater to adjust based on which room I am currently in etc etc.

However - the ecobee app is much better then the Homey ecobee devices which while improving looses connection to the sensors a lot. As of right now only one of my five sensors is communicating with Homey correctly.

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Thanks for your reply :slight_smile:

The Nest appears to require a special CV (with zone support) to be able to heat specific rooms on demand, so that’s probably not what I’m looking for. I’m not sure if that requires special piping in the house?

The Honeywell system seems to be a propriety system. So that the thermostat manages specific Honeywell valves.

The ecobee seems to be a contestant depending on what is meant by ‘control the HVAC mode’ in the app desciption.

What I’m looking for is that Homey can initiate the OpenTherm commands (be it native or via a thermostat). So when one room requires heat, that Homey opens the valve in that room and tells the boiler to start heating and pumping and if possible if two rooms require heat it heats a bit harder, etc.

you would need a opentherm translator. And some flows to control the whole heating. Would require some programming though. But it is certainly doable.
Edit: i do have the Honeywell Evohome and must say it works perfect. Evenso that i doubt you can outperform their decades of skill with some simple homey flows. If homey crashes or doesn’t function then ur either end up with a large heating bill or a cold house. It not the first time a homey driver got update and u have to repair the flows. On the other hand, the evohome responds fast, does what you want and has Google home integration. And is a separate system that won’t easily fail.

About the Honeywell Evohome. Does that ‘require’ an active internet connection?
As in. Does the app work without internet (e.g. your internet connection at home fails, Honeywell has a disruption, or, worst case: Honeywell decides to stop their support for the product)

no it works without internet. offcourse you can’t remotely control it if this occures.
honeywell stopping their support is highly unlikely. they support even 30 year old stuff. by the time they stop support your device is most probably allready died. :smiley:
edit: i work in installers sector and i can assure you this is the best controller for your heating system. backed by many years of experience and evohome itself is a tested for over 10 years and auto-learns. connection with homey, google assistent, its own app is flawless. its solid as a rock. i work a lot in hospital installations and they use honeywell in 99% of the hospitals in netherlands. also tested danfoss/heatit/nest etc. and none of them come even close to the efficiency of evohome in respect to usage , power consumption, ease of installation and daily use.

Of course dropping support is extremely unlikely, but it feels wrong, that if you are in your own house, that connectivity goes via Internet.

I have a Dyson air purifier, which I couldn’t control in my own house, because Dyson had a server disruption. (of code the basic functions worked via the infra red remote, but the more advanced stuff was unavailable)

Given your edit, I will seriously concider the Evohome. Can I send you a pm if I have specific questions?

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That thing looks 30 years old;)

Unlike the dyson you can control every function offline. It also runs battery operated so you can take the control unit off the wall and do the programming. It has a very good manual and built-in ‘wizard’ to make setting it up easy. Installation was quite easy. I have a automatic valve in the mains cabinet that was controlled with on/off from the thermostate, so i just reused the 2 wires and put the powersupply of the evohome next to the valve and the 2 outgoing wires to the controller where the original thermostat was. There is native remote control through homey and Google assistant which works very well. Batteries last a very long time compared to the other solutions i had before (danfoss, eurtronics etc). Also now finally the 2nd floor is heated up properly, which wasn’t the case with any of the other solutions. I programmed it so that in case outside temp is above 17degree C it automatically switch off the heatingsystem. All in all it saved me allready about 40€ in the last 3 months. So I’m quite convinced it’ll earn itself back in time. Please take note that you must have a bypass in the heatingsystem or leave one heater open as it will throttle the kettle to much with opentherm otherwise. Also allow the evohome a couple weeks to autolearn your system. You can PM, happy to help but not here often.

For heating it is not necessary that you have the same app then for lights and switches. So I would go with honeywell. Their thermostats are really perfect. You can control the thermostat without internet, but I think the app does not work without internet.

Thank you for your reply. You’re obviously very enthousiastic with your solution. (which is always nice to see :slight_smile: ) What I was hoping for, was that Homey could take over the function of the wall unit. I already have the Eurotronic valves, which work absolutely terrific with collective heating in appartments (blokverwarming) as that central boiler is ‘always on’ and automatically starts pumping harder on demand (appearently it detects the resistance in the water flow).

What I was hoping for was a simple way to talk to the boiler in my future house and just tell it to start heating/pumping when one of the Eurotronic valves request heat. So as you said, an Opentherm Translator would suffice for that. I’ll look into that soon, but if it isn’t feasable with my level of knowledge, I’ll probably look for the Honeywell solution.

And as I said. It just ‘feels’ wrong to have equipment in my own house and I have to communicate with it via internet (of course I don’t have to, but you know what I mean). I really don’t understand why people seem to accept that. Why would you want to be depenend on your internet connection for controlling equipment in your own house.
Look at Homey. Homey doesn’t need an active internet connection to manage the stuff in your own house. (except for the stuff that goes to the internet of course, but the Homey app works just fine without an internet connection)

I would take an on/off boiler in combination with a fibaro duo switch. The fibaro switch is potential free so it can on/off your future boiler and all the control could be done by Homey. Without internet and homey you can switch it manual with a basic wall switch. Nevertheless it won’t come even close to the evohome.
About the internet, I’m not worried about that at all. I can’t even remember the last time it was offline for longer then an hour. Probably somewhere in 1998 when i had casema 4kbit internet. I now have 500/500mbit glasfiber, so unlikely it has bandwidth shortage. Also i run Google home so it needs internet to control my house. You’ll get used to it lol. I once was like you so i get it, but yeah everything has it’s price.

I have had the best experience with the Tado system in my house. Check if it is compatible with your heating system and try it out. The nice thing on top is that the Tado Geofencing works a lot better than Homeys system and I use that to control the Home/Away status of everyone in the house!

Thank you for your reply. The Tado’s are always internet-driven from what I can tell. This is exactly what I’m trying to avoid :slight_smile: (( I don’t like the idea that I need an internet connection to manage stuff in my own house ))
This is exactly why I purchased the Eurotronic devices back then.

I’ll that that option into account as well. (the Fibaro switch)
As for the internet connected stuff. It’s partly on principle that I find it strange that I need an internet connection in order to manage stuff in my own house. Since I live in The Netherlands, I’m not scared of bandwidth limitations of course. Even the smallest ADSL lines are more than sufficient for a simple thermostat along side surfing/mailing.

Interesting remark. In the past I didn’t care, but lately I’m starting to really get annoyed by the sloppy/lazy designs of manufacturers. For Google I understand. Their core business is based on profiling you (no judgement on Google of course, just fact) so they can offer you custom advertisements. But for all the other companies, it’s just lazy design. (Since they also want to offer ‘online’, they don’t want to also create ‘local’, which of course is extra effort and something extra to maintain)

With that in mind. I already have Homey that I can manage from the internet, so the rest in my house shouldn’t need to. It has happened more than once that IOT devices were compromised and used in botnets.
The fact that people either don’t seem to care or don’t seem to understand the potential security risks is something really troubling to me. I’m happy that the Dutch government and TNO are currently investigating exactly this. So hopefully Europe will enforce some behaviour in a few years.

I don’t know how well the eurotronic devices are working with your homey, but mine were absolutely horrific. It doesn’t matter where I place Homey, the communication between my spirit z and homey just would not run smooth.

I understand what you are trying to achieve since that also was a goal of mine. However, if you just replace the radiator controls with the spirit z then you won’t really be doing yourself any favors. Allow me to explain:

Lets say it’s winter and the heater has done its job and gotten the house to the temperature that you desire. The thermostats all restrict the flow of water to the radiators which is a good start. BUT: Your central heating is still going to be heating the water and keeping it at a certain temperature. This would be like you getting in your car, pulling the handbrake and then driving down the road.

I actually had an old heating unit (built in 1968) in my basement until the end of last year. I didn’t really save any money by installing the Spirit Z. Now that I have a “newer” unit and Tado working with the spirit z its a different story. Tado actually takes the forecast into consideration, plus the amount of sunlight coming in the house which also heats it. When the house is at the desired temperature it then tells the heater to reduce the heat which is where you actually save money. Once Tado needs some more heat it will gradually increase the requested amount of heating from your unit until the desired temperature is reached.

Other benefits: Once you leave your house it automatically reduces the temperature in the house, and once you start coming back home in increases the heat. I have been hundreds of kilometers away from home and Tado really did start noticing when I was coming back home and increased the heat so that the house was nice and warm when we got back. I also used the geofencing to set my house in an “away” mode where all the lights would turn off and would not turn back on if motion was detected. (Our dogs would trigger then motion sensors and the lights would come on even though nobody was home). I also had a flow that when Tado registered someone was coming back home, it would turn on the outside lights if the sun hat set.

The range of Homey’s zwave is very poor indeed. I purchased a few smart plugs (tussenstekkers in Dutch) to act as zwave repeaters. Funny thing is that the Homey sphere is in the middle of my appartment. The plug in one corner of the appartment and the radiator head in the far corner of the smart plug and that worked great, but anyway :slight_smile:

Since I live in an apartment I have collective heating (blokverwarming in Dutch), so that heating unit is warm 24/7 in the seasons, so throttling the heating unit isn’t an issue for me. The unit apparently does have a smart system that when little heat is requested (resistance on the water pump or something, that’s way I understood of it anyway) that it slows down heating and with a properly insulated boiler in it, only little heat is lost (only the heat in the pipes of course)

I use a Homey app to work as a thermostat in my house. I programmed it in accordance to my household’s daily routines, so no hassle with 40 flows, just one app in a nice interface. The Homey app also allows quick settings for ‘Home today’ or ‘Not in the house today’ for quick exceptions. I never used geofencing, but that was something I could also have done of course, either via Homey’s function (not sure how well that works), or via IFTTT if I wanted to.

This all functions very well and very comfortable without any need for extra cloud-services. Just local homey.

Quick remark:

It would be more like letting your car run stationary since you’re already at your destination, and with newer central heating units only very little heat is lost as they are very well insulated. But you are right of course that, they shouldn’t need to heat up if it isn’t necessary. :slight_smile:

actually Shelly has local connection and works with homey , its like fibaro but half cheaper and no internet needed per se . this sounds like the thing you desire.
check it here Shelly
homey app for shelly APP

eurtronic works nice if you set the interval to 1 minute and hook it up to a adapter. with batteries they run out in 2 months and faster when you shorten the interval. it needs one hop between second floor and groundfloor so z-wave is not a problem.
there is also no way period that you can get the same results as the honeywell, it is way more advanced and smarter then you can ever program into homey. it would take up all resources also. i tried many things on a normal boiler, cityheating (even put a motorised valve in between to control it), HR boiler, and blockheating. switches, relais, heatit, nest, popp, danfoss, watts, etc. there is no device that comes close to the evohome.