Modbus Climate issue

So I have 2 working modbus servers I’m polling with several sensor and switch entities.
I’m trying to add a climate entity to one but when adding:

climates:
  - name: Thermia_Heat_Clim
    target_temp_register: 5

Check configuration is just an infinite load, restarting homeassistant gives an error just saying ‘address’

In the logs I can’t find anything meaningful, any tips?

Logger: homeassistant.components.websocket_api.http.connection
Source: components/websocket_api/commands.py:226
Integration: Home Assistant WebSocket API (documentation, issues)
First occurred: 17:21:59 (1 occurrences)
Last logged: 17:21:59

[139857353638464] 'address'
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/components/websocket_api/commands.py", line 226, in handle_call_service
    await hass.services.async_call(
  File "/usr/src/homeassistant/homeassistant/core.py", line 2012, in async_call
    response_data = await coro
                    ^^^^^^^^^^
  File "/usr/src/homeassistant/homeassistant/core.py", line 2049, in _execute_service
    return await target(service_call)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/src/homeassistant/homeassistant/helpers/service.py", line 986, in admin_handler
    await result
  File "/usr/src/homeassistant/homeassistant/components/homeassistant/__init__.py", line 168, in async_handle_core_service
    errors = await conf_util.async_check_ha_config_file(hass)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/src/homeassistant/homeassistant/config.py", line 973, in async_check_ha_config_file
    res = await check_config.async_check_ha_config_file(hass)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/src/homeassistant/homeassistant/helpers/check_config.py", line 180, in async_check_ha_config_file
    config = config_schema(config)
             ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/voluptuous/schema_builder.py", line 272, in __call__
    return self._compiled([], data)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/voluptuous/schema_builder.py", line 595, in validate_dict
    return base_validate(path, iteritems(data), out)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/voluptuous/schema_builder.py", line 387, in validate_mapping
    cval = cvalue(key_path, value)
           ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/voluptuous/validators.py", line 229, in _run
    return self._exec(self._compiled, value, path)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/voluptuous/validators.py", line 353, in _exec
    v = func(path, v)
        ^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/voluptuous/schema_builder.py", line 818, in validate_callable
    return schema(data)
           ^^^^^^^^^^^^
  File "/usr/src/homeassistant/homeassistant/components/modbus/validators.py", line 242, in duplicate_entity_validator
    addr = str(entry[CONF_ADDRESS])
               ~~~~~^^^^^^^^^^^^^^
KeyError: 'address'

I’m not personally familiar with the ‘climate’ entity, but from what I can see, that entity type is something that would apply to actual devices that you add to HA. The closest thing I can find to what I think you’re trying to do is the Generic Thermostat integration. Does that seem right?

BTW, what model of Thermia do you have, and how have you done the modbus integration? I have an iTec, and I have yet to find a way to integrate it (aside from buying there online module and using their paid cloud service).