Anyone implemented an intelligent temperature/thermostat control?

Hi guys,

I am using two Danfoss LC13 thermostats in my living room. Currently they are controlled by some simple rules (set temperature up in the morning and down in the evening, weekdays and weekend separated). Additionally I am using a temperature sensor to get the current temperature.

This morning according to the rule the set temperature was correctly set to 21°C. Before it was 18°C. But as it’s quite warm outside, the current temperature already is 22.5°C in the room. So the radiators heat up, but because of the current temperature they didn’t need to.

What should help is some kind of intelligent control which regulates the set temperature based on the current temperature. Is this a logical approach or isn’t this possible? Is there anyone here with similar “problems”?


Why did the radiator heat up if it was set to 21 deg, and the room was at 22.5 deg? It shouldn’t have heated up at all given that the LC13 is thermostatically controlled?

Maybe the temperature where the radiator is is slightly lower than the room temperature (eg if they are near the floor) in which case you might need to adjust the radiator temperature to account for this.

Maybe I’m missing something, but what does “thermostatically controlled” mean? The Danfoss is not linked to the room temperature sensor, so from where should the thermostat know the current temperature of the room?

Isn’t the LC13 a thermostatically controlled valve - so it has its own thermostat and temperature sensor and should only turn on when the temperature is below that temperature?

Well…I don’t know… :pensive:

If so, the desired intelligence would be automatically integrated into the valve and no “intelligent” rule would be necessary. I will search the web about this…


I’m pretty sure it does - you can certainly set the control temperature on this device, and it would be strange for a radiator valve to not control the temperature (even old mechanical ones control the temperature - badly of course! :slight_smile:).

Yes, indeed, that’s the way this little thing works …

i simply check the forecast for the day, and if the minimum temperature is over any threshold you define, the heating setpoints of the thermostats stay 5°C (in my case).
But as anyone else already wrote - this thing has is own loop!

Ok, thank you guys! I will have a look if this heating happens again when it’s warm in the room.

TRV’s have their own set of problems unrelated to automation and thermostats (Thermostatic Regulated Valves). Airflow around the TRV is a big one; if you put a shelf over the radiator, air cannot move around the TRV, and so will not have an accurate view of the temperature when it is controlling the radiator. Covering it up with drapes/curtains is even worse as it is completly cut off from the room temp. Temperature sensing should also be done at 1.5m high, whereas TRVs are mostly on radiators much lower. Being recessed a bit from the wall, and next to a cold window also makes sensing and regulation challenging for TRVs.

None of this has anything to do with thermostats or openhab.

Making matters worse, these “smart” TRVs don’t send the temperature as they see it, only the setpoint, so you can’t even tell what temp it thinks it is.

That depends on the thermostat of course - some do, some dont…

You raise some good points though…

I was referring to these TRVs from Danfoss… but I looked at them 3 years ago and know that they have been releasing different hardware and software versions since then so this could have of course changed.