OK, so I don’t have heat-on-demand (I have no smart TRV’s). I got one for Christmas to play with, but haven’t tried it out yet. If I understand you correctly, you want the TRV to call for heat within certain time-windows? That’s sounds possible but I haven’t programmed that.
Basically, I put a calibrated Hue temp sensor (any make will do) into each room and then load-balanced my radiators. That is to say, I adjusted each (manual) TRV until I got the right temp in each room for a given temp at the Hive thermostat.
My concern with on-demand TRV’s is that one may call for heat, then the next, then the next such that your boiler is always on but only ever servicing one radiator at a time. I’m not sure if that is a real concern or not, but I have no experience with them.
My use of the smart TRV’s would only be to turn upstairs radiators down when house_mode: awake
(i.e. during the day). It would then turn the upstairs TRVs on (back to the balanced point) when outside_light: dark
(i.e. in the evenings). …something like that, anyway.
My heating spec is as follows (let me know if you still want to have it):
Basic modes:
-
Heating: [off, on, scheduled, boost]
- Scheduled windows override
house_mode
but not presence
.
- This means I can set the heating at 6:30am before I get up (
house_mode: asleep
).
- I set this window to the default day temp setting so, when I do get up, nothing changes
- This effectively means I can set the time when
house_mode
is awake
) as house_mode: awake
is currently triggered on first movement downstairs after 7am.
- Now I think about it, I should add a time component to waking the house up.
- Outside of the scheduled windows (which sets a specific temp), the temp goes back to the default (based on
house_mode
and presence
).
- I have 4 scheduled windows (but easy to make more)
- On:
- has 3 temp defaults based on
house_mode
and presence
so:
- home and awake
- home and asleep
- away.
- …but I have never had to use ‘On’.
- Off:
- I personally set the ‘Off’ temp default to be my anti-frost temp.
- Boost
- Pushing the ‘boost’ button temperature increases relative temp by an amount (according to a default setting) for a duration (according to a default setting).
-
Hot water: [off, on, scheduled, boost]
- follows the same principles as heating but without any temp defaults and so not influenced by
house_mode
or presence
.
- The only default setting is boost duration.
In reality, the Hive heating is always on, but the temp setting varies according to the mode (above) and the influences (below). I typically leave the system in ‘scheduled’ mode all year round and rarely have to adjust the defaults.
Influences:
- House mode: {Awake, Asleep, Manual}
‘Awake’ is automated
‘asleep’ is set by a ‘good night button’
house_mode
can be manually set in my dashboard
- Presence: {home, away}
Both ‘home’ and ‘away’ are automated based on user and zone.home
Each mode and influence has a default temp setting for heating (which can be adjusted) and a boost setting for heating and duration.
After a couple of days getting the defaults right (and setting the schedule windows), I’ve been able to leave it almost completely alone. …hope that all makes sense.
Future
- My Hive is currently working via the Hive integration (which uses the Hive online account). Now that I have got it working as I want, I will changeover to using completely local control (without the modem device) using Zigbee2MQTT. I am only waiting for it to become warmer outside to make the switch.
- Integrate the single smart-TRV as mentioned above to see if I want to add this is as a proper influence.
Here are some screen shots of the control dash so you can get an idea…
Main dash button
Pushing that button takes you to the control screen…
- You can see:
- I am in ‘schedule mode’
- 4 scheduled windows are set and active
- We are in the 2nd scheduled window right now
- The boiler is heating right now
- The graph:
- The grey bars on the graph show when the boiler has been actually heating.
- the temp changes last night show when HA was being upgraded and some other docker-related updates so Hive defaulted to ‘off’ which for me is set to 12 °C.
- The default settings are hidden behind a drop-down so I don’t modify them by accident.
- The most important defaults (to me) are displayed on the screen but tapping them does nothing so I can’t change them by accident.
- I have to look in the drop-down to change them.
So, homing in on the ‘default settings’ drop-down…
Away defaults:
On defaults:
Schedule defaults (1st scheduled window showing):
‘Boost’ defaults:
[edited for content, typos and clarity - I posted too early by accident]