I found a way around to have multiple thermostats with a single set of automatons (not one set per thermostat).
configuration.yaml
climate:
- platform: mqtt
name: Bedroom heating
device:
identifiers: '00:1A:22:0C:XX:XX'
modes:
- "off"
- "auto"
- "heat"
precision: 0.5
min_temp: 4.5
max_temp: 29.5
temp_step: 0.5
mode_command_topic: "/eq3mqtt/00:1A:22:0C:XX:XX/trv_mode"
temperature_command_topic: "/eq3mqtt/00:1A:22:0C:XX:XX/trv_temp"
mode_state_topic: "/eq3mqtt/00:1A:22:0C:XX:XX/status"
mode_state_template: >-
{% if value_json.mode == "manual" %}
{% if value_json.temp == "4.5" %}
off
{% else %}
heat
{% endif %}
{% elif value_json.mode == "auto" %}
auto
{% endif %}
temperature_state_topic: "/eq3mqtt/00:1A:22:0C:XX:XX/status"
temperature_state_template: "{{value_json.temp}}"
current_temperature_topic: "/eq3mqtt/00:1A:22:0C:XX:XX/status"
current_temperature_template: "{{value_json.temp}}"
json_attributes_topic: "/eq3mqtt/00:1A:22:0C:XX:XX/status"
json_attributes_template: "{{ {'mac':value_json.trv, 'valve':value_json.valve, 'boost':value_json.boost, 'window':value_json.window, 'battery':value_json.battery} | tojson}}"
away_mode_state_topic: "/eq3mqtt/00:1A:22:0C:XX:XX/status"
away_mode_state_template: >-
{% if value_json.mode == "holiday" %}
on
{% else %}
off
{% endif %}
as you see I post and listen everything related to a given thermostat in its own topics /eq3mqtt/<mac address>/...
Then the automatisation for temperature becomes:
- alias: eq3mqtt_Temperature_Helper
description: ''
trigger:
- platform: mqtt
topic: /eq3mqtt/+/trv_temp
condition: []
action:
service: mqtt.publish
data_template:
payload: >
{% if trigger.payload == 4.5 %} {{trigger.topic.split('/')[2]}} off
{% else %} {{trigger.topic.split('/')[2]}} settemp {{trigger.payload}}
{% endif %}
topic: /eq3mqtt/radin/trv
Notice the wildcard to listen to all topics of all sensors, later I extract the MAC address from the topic that actually triggered the automation.
And the automation for modes (same trick as the temp automation):
- alias: eq3mqtt_Mode_Helper
description: ''
trigger:
- platform: mqtt
topic: /eq3mqtt/+/trv_mode
condition: []
action:
service: mqtt.publish
data_template:
payload: >
{% if trigger.payload == "heat" %} {{trigger.topic.split('/')[2]}} manual
{% else %} {{trigger.topic.split('/')[2]}} {{trigger.payload}}
{% endif %}
topic: /eq3mqtt/radin/trv
But now it is needed a kind of “forwarder” between the generic topic of the esp32_mqtt_eq3 and the individual topics of each thermostat:
- alias: eq3mqtt_status_proxy
trigger:
- platform: mqtt
topic: "/eq3mqtt/radout/status"
action:
service: mqtt.publish
data_template:
topic: "/eq3mqtt/{{ trigger.payload_json.trv }}/status"
payload: "{{ trigger.payload_json | tojson }}"
Here I extract the mac address from the json response.
For pulling the status of the thermostats, in case they are changed manually, I found that it is better to do it separately otherwise the ESP32 misses some messages and the thermostats are not updated.
I pull my different thermostats at different second every 2 minutes. (Not sure if it is too much and will affect the battery or not, I will see)
- alias: Pulling_Thermostat_Bedroom
description: ''
trigger:
- platform: homeassistant
event: start
- platform: time_pattern
minutes: /2
seconds: 15
condition: []
action:
- service: mqtt.publish
data_template:
payload: "00:1A:22:0C:XX:XX unlock"
topic: /eq3mqtt/radin/trv
I hope this helps others to add multiple thermostats 
