Official Honeywell evohome/Round Thermostat integration (EU-only)

Thanks for the quick response @zxdavb . So I have a few use cases, all of which are on one or more evohome zones:

  1. Guest mode on or off. Guest mode on should set the guest room radiator to follow schedule. If guest mode goes off then the radiator should be set to off (or a permanent override at say 15C)

  2. Occupied on/off. If I go out I want (most of) my rads to set to 15C. When I’m back it should follow schedule.

  3. If my TV is on then set living room to 22C, if it goes off the follow schedule.

How would you recommend I do this? Thanks!

Ah so I think I’ve mostly figured this out now… one bit I’m not clear on. Is it possible to set a permanent override to a specific temperature (i.e. not off / 5C but for example 22C)?

Set temp first (which will be until next scheduled setpoint), then switch to permanent override.

Got it, thanks!

I’ve been doing things like this - not sure if it’s a good approach:

When I’m at my other workplace, I’m not in my study at home, so:

 - service: climate.set_temperature
        temperature: 12

When I come back, I want to go back the scheduled temperature:

    - service: climate.set_temperature
        temperature: "{{ state_attr('', 'status').setpoints.current.temperature|float }}"
    - service: climate.set_preset_mode
        preset_mode: "none"

I think this works - there may be a better way?

For those of yo with a HGI80 (or similar)…

… something’s coming!

Great news… Is this likely to land before Christmas ?

@GadgetUK, @scstraus, @xAPPO & others:


Here is an indication how inaccurate the shaded are is - it is very underestimated. The upper graph is evohome, the lower graph is from the new evohome_rf integration.

Notice the room getting hotter where the red ‘arrow’ is pointed.

I know why this data is inaccurate - the problem is fixing it. If I can’t come up with a reasonable solution, I will have to remove this feature.

People have asked me, so here’s teh answer:

The reason why evohome is inaccurate is because it doesn’t take into account the 0.5C dead band

  • when calling for heat, the zone continues to call for heat until it is 0.5C warmer than the setpoint and,
  • when losing temperature, the zone wont resume calling for heat until it is 0.5C cooler than the setpoint

The ‘when’ qualifiers are important! That is, it is not sufficient for the zone to be 0.1C cooler that its setpoint fro a call for heat to be made! For this specific reason, it may be difficult to modify evohome to make this information more accurate.

If you look at the following post, you see that evohome_rf indicates more than just wether the zones is calling for heat - it also indicates how strong that call is (0-100%):

Coming soon:


… and:

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I really like what I saw here and I would like to ask if you think that among other TRV options (Tado, EQ3 Max! Neatamo or some Fibaro stuff) Honeywell option is still the one you would go with when you would have an opportunity to start over? My scenario is 3 rooms - bathroom with one heater, bedroom with one and living room with two. I would like to have some simple day/night automation and possibly no cloud (which is not the case for Evohome I believe).

I think with the HGI-80 integration, it will be the near perfect solution, where you can run it cloud, local only with honeywell controller, or local only without honeywell controller. It will cover pretty much any scenario. Even without HGI-80 it works very well from cloud component (though honeywell does not have perfect uptime, it’s pretty good), I very much like having the controller at home in case I screw up something on the home assistant side… So yes, I would repeat this purchase. That’s largely thanks to @zxdavb

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That is great to hear. So I would need something like let’s say Honeywell HR92 and the HGI80 (or similar) to act as evohome controller? Hmm…I need to look at that closely, quick google gave me prices for the controller around twice as much as for one TRV.

Yes he’s working on HGI-80 integration now. Still early days but looks like it will work. Scroll up in the thread, he links to it.

I did look through the thread, just wondering about opinions of current users if they would switch to some different TRV (system in general) for their use case :slight_smile: I would prefer something local without cloud, that’s where evohome is a questionmark for me :slight_smile:

I wouldn’t switch. I researched all the options thoroughly before buying and I think I made the best choice for me.

And, if I may, what components of the system you’re using? I’m trying to asses the bare minimum for it to work decently with HA, possibly without cloud, but I may live with it for now. As I mentioned I am looking at HR91/92 that seems to be reasonably priced for the features it offer.