Control central boiler

Hi everyone, I tried to search for a solution on here but I did not manage to solve my issue:

I have a Sonoff Zigbee TRV for every radiator in my Apartment which I control through scenes. I have a central boiler which is controlled by a thermostat in the living room. I have connected the boiler to HA using EMS-ESP and as far as I can see, I cannot control it directly, but I can control the boiler indirectly by cranking the thermostat temperature up/down.

So my plan is to check if any of the TRVs are trying to heat. If yes, crank the thermostat up to 25°, and if not, put it down to 15°. I created the following automation, but it always only cranks the thermostat up as if one of the TRVs is trying to heat, even when I made sure none of them are. Thank you in advance for any help!

alias: Boiler
description: ""
trigger:
  - platform: time_pattern
    minutes: /1
condition: []
action:
  - if:
      - condition: or
        conditions:
          - condition: state
            entity_id: climate.heizung_wohnzimmer_thermostat
            state: heat
            for:
              hours: 0
              minutes: 0
              seconds: 0
          - condition: state
            entity_id: climate.heizung_badezimmer_thermostat
            state: heat
            for:
              hours: 0
              minutes: 0
              seconds: 0
          - condition: state
            entity_id: climate.heizung_kuche_thermostat
            state: heat
            for:
              hours: 0
              minutes: 0
              seconds: 0
          - condition: state
            entity_id: climate.heizung_schlafzimmer_thermostat
            state: heat
            for:
              hours: 0
              minutes: 0
              seconds: 0
          - condition: state
            entity_id: climate.heizung_durchreiche_thermostat
            state: heat
            for:
              hours: 0
              minutes: 0
              seconds: 0
    then:
      - device_id: 50704a2dd670d0a042189f9eb3bd26e6
        domain: number
        entity_id: c7c7c65f819f9512911c13ff2a7f8de1
        type: set_value
        value: 25
    else:
      - device_id: 50704a2dd670d0a042189f9eb3bd26e6
        domain: number
        entity_id: c7c7c65f819f9512911c13ff2a7f8de1
        type: set_value
        value: 15
mode: single