Boiler switching with TRVs

Configuration
1

I plan a setup containing several TRVs such as Aqara E1 or Shelly BLU connected to a HA Green. I will command on each zone using HA calendars.

How through do I switch the gas boiler on and off? On is easier as I presumably just commands it on via my Shelly relay when one or more zones are turned on. Off is harder because it needs to go off if all the rooms get to temperature and all the valves thus shut down the water flow. How do I detect that state? Also, once a room temperature drops again how do I detect that and turn the boiler on again?

Is this boiler switching automatically built into the Aqara and Shelly implementation in HA or do I have to set it up?

2

Still not getting anywhere with this. Any advice please?

My test setup is one Aqara EI valve wth a bulb next to it to simulate the room heating it. A relay switches on the bulb to simulate the boiler coming on. I have got the calendar to send a target temperature to this TRV but can’t work out how to turn off the bolier when target is reached.

Indeed I can’t find any help pages that advise how to control an E1 from HA. Aqara’s info assumes you use their hub installed which I don’t intend to use as direct HA to E1 comms is allegedly possible and certainly works to some extent.