Nest Thermostat + Aqara temperature sensors > heat based on coldest room, not the room where the thermostat is

Hi all,

I am trying to set an artificial zone-heating system. The setup is:

  1. Nest Thermostat in a relatively warm bedroom (limited by the distance to the hub - no real way to move it anywhere else)
  2. Aqara temperature/humidity sensors in every room, and Aqara TRVs in all the bedrooms getting readings from the sensors for ‘actual temperature’

What I’d like to do is have HA judge when any of the bedrooms need heating (using the target heat in each of the TRVs), and increment the Nest target temp just until all the rooms are at the desired temp.

Bedroom 1 (where the thermostat 1 lives) - desired temp 22 degrees. Actual temp almost always above 22 degrees, the Nest never calls for more heat.
Bedroom 2 - desired temp 23 degrees. Often actual temp will be below that - so I’d like for an automation that increments Nest’s target temp by the difference, for example - the ‘deficit’ in bedroom 2. When Bedroom 2 reaches the target temp, then the Nest should revert to the original 22.

Using Homekit integration to reach all TRVs and sensors, and the Google Nest integration. Could have connected the sensors/TRVs directly via ZHA but I wanted to use the ability to override the TRV sensor temperature using an external sensor in each room, to avoid issues with incorrect measurements.

Can anyone help please? Thank you in advance!


This is more or less exactly what I am trying figure out.

I have a Nest Thermostat in the hall - and the target temperature is say 21 degrees. I am in the lounge all day and the temperature will be (from my aqara sensor) say 19 degrees. I then need to manually put the heating up to say 22. I am trying to figure out an automation that will take my temperature and then add the difference on to the thermostat so it will heat. I know the hallway will get hotter (dont care). When the lounge hits say 22, then turn off the thermostat. I was trying with functions in Node Red but didn’t get very far