diff --git a/homeassistant/components/duco/coordinator.py b/homeassistant/components/duco/coordinator.py
index 10cbf619c96e..e0755b153f09 100644
--- a/homeassistant/components/duco/coordinator.py
+++ b/homeassistant/components/duco/coordinator.py
@@ -10,8 +10,15 @@ from duco_connectivity.exceptions import (
     DucoConnectionError,
     DucoError,
     DucoResponseError,
+    DucoUnsupportedCapabilityError,
+)
+from duco_connectivity.models import (
+    BoardInfo,
+    Node,
+    NodeListActionItemList,
+    NodeName,
+    VentilationTemperatureInfo,
 )
-from duco_connectivity.models import BoardInfo, Node, NodeListActionItemList, NodeName
 
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.core import HomeAssistant
@@ -26,7 +33,7 @@ _LOGGER = logging.getLogger(__name__)
 type DucoConfigEntry = ConfigEntry[DucoCoordinator]
 
 
-@dataclass
+@dataclass(slots=True, kw_only=True)
 class DucoData:
     """Data returned by the Duco coordinator."""
 
@@ -34,6 +41,7 @@ class DucoData:
     node_actions: NodeListActionItemList
     rssi_wifi: int | None
     time_filter_remain: int | None
+    ventilation_temperatures: VentilationTemperatureInfo | None
 
 
 class DucoCoordinator(DataUpdateCoordinator[DucoData]):
@@ -42,6 +50,7 @@ class DucoCoordinator(DataUpdateCoordinator[DucoData]):
     config_entry: DucoConfigEntry
     board_info: BoardInfo
     _supports_time_filter_remain: bool
+    _supports_ventilation_temperatures: bool
     _configured_node_names: dict[int, str]
 
     def __init__(
@@ -61,6 +70,7 @@ class DucoCoordinator(DataUpdateCoordinator[DucoData]):
         self.client = client
         self._configured_node_names = {}
         self._supports_time_filter_remain = True
+        self._supports_ventilation_temperatures = True
 
     async def _async_load_node_names(self) -> None:
         """Load configured Duco node names during setup."""
@@ -175,9 +185,26 @@ class DucoCoordinator(DataUpdateCoordinator[DucoData]):
                 time_filter_remain = await self.client.async_get_time_filter_remaining()
                 self._supports_time_filter_remain = time_filter_remain is not None
 
+        ventilation_temperatures = (
+            self.data.ventilation_temperatures if self.data else None
+        )
+        if self._supports_ventilation_temperatures:
+            try:
+                ventilation_temperatures = (
+                    await self.client.async_get_ventilation_temperature_info()
+                )
+            except DucoUnsupportedCapabilityError:
+                ventilation_temperatures = None
+                self._supports_ventilation_temperatures = False
+            except DucoError as err:
+                _LOGGER.debug(
+                    "Could not fetch Duco ventilation temperatures", exc_info=err
+                )
+
         return DucoData(
             nodes={node.node_id: node for node in nodes},
             node_actions=node_actions,
             rssi_wifi=rssi_wifi,
             time_filter_remain=time_filter_remain,
+            ventilation_temperatures=ventilation_temperatures,
         )
diff --git a/homeassistant/components/duco/sensor.py b/homeassistant/components/duco/sensor.py
index faad3737c271..63e8f16cd27d 100644
--- a/homeassistant/components/duco/sensor.py
+++ b/homeassistant/components/duco/sensor.py
@@ -18,6 +18,7 @@ from homeassistant.const import (
     SIGNAL_STRENGTH_DECIBELS_MILLIWATT,
     EntityCategory,
     UnitOfRatio,
+    UnitOfTemperature,
     UnitOfTime,
 )
 from homeassistant.core import HomeAssistant, callback
@@ -156,6 +157,70 @@ BOX_SENSOR_DESCRIPTIONS: tuple[DucoBoxSensorEntityDescription, ...] = (
         entity_registry_enabled_default=False,
         value_fn=lambda coordinator: coordinator.data.rssi_wifi,
     ),
+    DucoBoxSensorEntityDescription(
+        key="outdoor_air_temperature",
+        translation_key="outdoor_air_temperature",
+        device_class=SensorDeviceClass.TEMPERATURE,
+        state_class=SensorStateClass.MEASUREMENT,
+        native_unit_of_measurement=UnitOfTemperature.CELSIUS,
+        supported_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures is not None
+            and coordinator.data.ventilation_temperatures.temp_oda is not None
+        ),
+        value_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures.temp_oda
+            if coordinator.data.ventilation_temperatures
+            else None
+        ),
+    ),
+    DucoBoxSensorEntityDescription(
+        key="supply_air_temperature",
+        translation_key="supply_air_temperature",
+        device_class=SensorDeviceClass.TEMPERATURE,
+        state_class=SensorStateClass.MEASUREMENT,
+        native_unit_of_measurement=UnitOfTemperature.CELSIUS,
+        supported_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures is not None
+            and coordinator.data.ventilation_temperatures.temp_sup is not None
+        ),
+        value_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures.temp_sup
+            if coordinator.data.ventilation_temperatures
+            else None
+        ),
+    ),
+    DucoBoxSensorEntityDescription(
+        key="extract_air_temperature",
+        translation_key="extract_air_temperature",
+        device_class=SensorDeviceClass.TEMPERATURE,
+        state_class=SensorStateClass.MEASUREMENT,
+        native_unit_of_measurement=UnitOfTemperature.CELSIUS,
+        supported_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures is not None
+            and coordinator.data.ventilation_temperatures.temp_eta is not None
+        ),
+        value_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures.temp_eta
+            if coordinator.data.ventilation_temperatures
+            else None
+        ),
+    ),
+    DucoBoxSensorEntityDescription(
+        key="exhaust_air_temperature",
+        translation_key="exhaust_air_temperature",
+        device_class=SensorDeviceClass.TEMPERATURE,
+        state_class=SensorStateClass.MEASUREMENT,
+        native_unit_of_measurement=UnitOfTemperature.CELSIUS,
+        supported_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures is not None
+            and coordinator.data.ventilation_temperatures.temp_eha is not None
+        ),
+        value_fn=lambda coordinator: (
+            coordinator.data.ventilation_temperatures.temp_eha
+            if coordinator.data.ventilation_temperatures
+            else None
+        ),
+    ),
 )
 
 
diff --git a/homeassistant/components/duco/strings.json b/homeassistant/components/duco/strings.json
index 2761903e336b..4f5eb782f93a 100644
--- a/homeassistant/components/duco/strings.json
+++ b/homeassistant/components/duco/strings.json
@@ -73,6 +73,12 @@
       }
     },
     "sensor": {
+      "exhaust_air_temperature": {
+        "name": "Exhaust air temperature"
+      },
+      "extract_air_temperature": {
+        "name": "Extract air temperature"
+      },
       "filter_remaining": {
         "name": "Filter remaining"
       },
@@ -82,6 +88,12 @@
       "iaq_rh": {
         "name": "Humidity air quality index"
       },
+      "outdoor_air_temperature": {
+        "name": "Outdoor air temperature"
+      },
+      "supply_air_temperature": {
+        "name": "Supply air temperature"
+      },
       "target_flow_level": {
         "name": "Target flow level"
       },
diff --git a/tests/components/duco/conftest.py b/tests/components/duco/conftest.py
index b6963ad8a761..655dd0dfc935 100644
--- a/tests/components/duco/conftest.py
+++ b/tests/components/duco/conftest.py
@@ -23,6 +23,7 @@ from duco_connectivity import (
     NodeMotorStateInfo,
     NodeSensorInfo,
     NodeVentilationInfo,
+    VentilationTemperatureInfo,
 )
 import pytest
 
@@ -178,6 +179,17 @@ def mock_lan_info() -> LanInfo:
     )
 
 
+@pytest.fixture
+def mock_ventilation_temperature_info() -> VentilationTemperatureInfo:
+    """Return mock ventilation temperatures in Celsius."""
+    return VentilationTemperatureInfo(
+        temp_oda=5.5,
+        temp_sup=18.2,
+        temp_eta=21.4,
+        temp_eha=8.1,
+    )
+
+
 @pytest.fixture
 def mock_nodes() -> list[Node]:
     """Return a list of nodes covering all supported types."""
@@ -235,6 +247,7 @@ def mock_duco_client(
     mock_lan_info: LanInfo,
     mock_nodes: list[Node],
     mock_node_actions: NodeListActionItemList,
+    mock_ventilation_temperature_info: VentilationTemperatureInfo,
 ) -> Generator[AsyncMock]:
     """Return a mocked DucoClient used by both the integration and config flow."""
     with (
@@ -255,6 +268,9 @@ def mock_duco_client(
         client.async_get_node_configs.return_value = node_configs_from_nodes(mock_nodes)
         client.async_get_node_actions.return_value = mock_node_actions
         client.async_get_time_filter_remaining.return_value = 180
+        client.async_get_ventilation_temperature_info.return_value = (
+            mock_ventilation_temperature_info
+        )
         client.async_get_diagnostics.return_value = [
             DiagComponent(component="Ventilation", status="Ok")
         ]
diff --git a/tests/components/duco/snapshots/test_sensor.ambr b/tests/components/duco/snapshots/test_sensor.ambr
index 3b2801d29af0..1be688fcc237 100644
--- a/tests/components/duco/snapshots/test_sensor.ambr
+++ b/tests/components/duco/snapshots/test_sensor.ambr
@@ -835,6 +835,122 @@
     'state': '90',
   })
 # ---
+# name: test_sensor_entities_state[sensor.living_exhaust_air_temperature-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': dict({
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+    }),
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'sensor',
+    'entity_category': None,
+    'entity_id': 'sensor.living_exhaust_air_temperature',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Exhaust air temperature',
+    'options': dict({
+      'sensor': dict({
+        'suggested_display_precision': 1,
+      }),
+    }),
+    'original_device_class': <SensorDeviceClass.TEMPERATURE: 'temperature'>,
+    'original_icon': None,
+    'original_name': 'Exhaust air temperature',
+    'platform': 'duco',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'exhaust_air_temperature',
+    'unique_id': 'aa:bb:cc:dd:ee:ff_1_exhaust_air_temperature',
+    'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
+  })
+# ---
+# name: test_sensor_entities_state[sensor.living_exhaust_air_temperature-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      <EntityStateAttribute.DEVICE_CLASS: 'device_class'>: 'temperature',
+      <EntityStateAttribute.FRIENDLY_NAME: 'friendly_name'>: 'Living Exhaust air temperature',
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+      <EntityStateAttribute.UNIT_OF_MEASUREMENT: 'unit_of_measurement'>: <UnitOfTemperature.CELSIUS: '°C'>,
+    }),
+    'context': <ANY>,
+    'entity_id': 'sensor.living_exhaust_air_temperature',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': '8.1',
+  })
+# ---
+# name: test_sensor_entities_state[sensor.living_extract_air_temperature-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': dict({
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+    }),
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'sensor',
+    'entity_category': None,
+    'entity_id': 'sensor.living_extract_air_temperature',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Extract air temperature',
+    'options': dict({
+      'sensor': dict({
+        'suggested_display_precision': 1,
+      }),
+    }),
+    'original_device_class': <SensorDeviceClass.TEMPERATURE: 'temperature'>,
+    'original_icon': None,
+    'original_name': 'Extract air temperature',
+    'platform': 'duco',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'extract_air_temperature',
+    'unique_id': 'aa:bb:cc:dd:ee:ff_1_extract_air_temperature',
+    'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
+  })
+# ---
+# name: test_sensor_entities_state[sensor.living_extract_air_temperature-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      <EntityStateAttribute.DEVICE_CLASS: 'device_class'>: 'temperature',
+      <EntityStateAttribute.FRIENDLY_NAME: 'friendly_name'>: 'Living Extract air temperature',
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+      <EntityStateAttribute.UNIT_OF_MEASUREMENT: 'unit_of_measurement'>: <UnitOfTemperature.CELSIUS: '°C'>,
+    }),
+    'context': <ANY>,
+    'entity_id': 'sensor.living_extract_air_temperature',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': '21.4',
+  })
+# ---
 # name: test_sensor_entities_state[sensor.living_filter_remaining-entry]
   EntityRegistryEntrySnapshot({
     'aliases': list([
@@ -890,6 +1006,64 @@
     'state': '180',
   })
 # ---
+# name: test_sensor_entities_state[sensor.living_outdoor_air_temperature-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': dict({
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+    }),
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'sensor',
+    'entity_category': None,
+    'entity_id': 'sensor.living_outdoor_air_temperature',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Outdoor air temperature',
+    'options': dict({
+      'sensor': dict({
+        'suggested_display_precision': 1,
+      }),
+    }),
+    'original_device_class': <SensorDeviceClass.TEMPERATURE: 'temperature'>,
+    'original_icon': None,
+    'original_name': 'Outdoor air temperature',
+    'platform': 'duco',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'outdoor_air_temperature',
+    'unique_id': 'aa:bb:cc:dd:ee:ff_1_outdoor_air_temperature',
+    'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
+  })
+# ---
+# name: test_sensor_entities_state[sensor.living_outdoor_air_temperature-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      <EntityStateAttribute.DEVICE_CLASS: 'device_class'>: 'temperature',
+      <EntityStateAttribute.FRIENDLY_NAME: 'friendly_name'>: 'Living Outdoor air temperature',
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+      <EntityStateAttribute.UNIT_OF_MEASUREMENT: 'unit_of_measurement'>: <UnitOfTemperature.CELSIUS: '°C'>,
+    }),
+    'context': <ANY>,
+    'entity_id': 'sensor.living_outdoor_air_temperature',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': '5.5',
+  })
+# ---
 # name: test_sensor_entities_state[sensor.living_signal_strength-entry]
   EntityRegistryEntrySnapshot({
     'aliases': list([
@@ -996,6 +1170,64 @@
     'state': 'unknown',
   })
 # ---
+# name: test_sensor_entities_state[sensor.living_supply_air_temperature-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': dict({
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+    }),
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'sensor',
+    'entity_category': None,
+    'entity_id': 'sensor.living_supply_air_temperature',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Supply air temperature',
+    'options': dict({
+      'sensor': dict({
+        'suggested_display_precision': 1,
+      }),
+    }),
+    'original_device_class': <SensorDeviceClass.TEMPERATURE: 'temperature'>,
+    'original_icon': None,
+    'original_name': 'Supply air temperature',
+    'platform': 'duco',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'supply_air_temperature',
+    'unique_id': 'aa:bb:cc:dd:ee:ff_1_supply_air_temperature',
+    'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
+  })
+# ---
+# name: test_sensor_entities_state[sensor.living_supply_air_temperature-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      <EntityStateAttribute.DEVICE_CLASS: 'device_class'>: 'temperature',
+      <EntityStateAttribute.FRIENDLY_NAME: 'friendly_name'>: 'Living Supply air temperature',
+      <SensorEntityCapabilityAttribute.STATE_CLASS: 'state_class'>: <SensorStateClass.MEASUREMENT: 'measurement'>,
+      <EntityStateAttribute.UNIT_OF_MEASUREMENT: 'unit_of_measurement'>: <UnitOfTemperature.CELSIUS: '°C'>,
+    }),
+    'context': <ANY>,
+    'entity_id': 'sensor.living_supply_air_temperature',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': '18.2',
+  })
+# ---
 # name: test_sensor_entities_state[sensor.living_target_flow_level-entry]
   EntityRegistryEntrySnapshot({
     'aliases': list([
diff --git a/tests/components/duco/test_init.py b/tests/components/duco/test_init.py
index 24f906507d37..3cf9aee5b3c9 100644
--- a/tests/components/duco/test_init.py
+++ b/tests/components/duco/test_init.py
@@ -15,10 +15,12 @@ from duco_connectivity import (
     LanInfo,
     Node,
     NodeListActionItemList,
+    VentilationTemperatureInfo,
 )
 from freezegun.api import FrozenDateTimeFactory
 import pytest
 
+from homeassistant.components.duco.const import SCAN_INTERVAL
 from homeassistant.config_entries import ConfigEntryState
 from homeassistant.const import Platform
 from homeassistant.core import HomeAssistant
@@ -158,6 +160,42 @@ async def test_setup_entry_ignores_lan_info_failures(
     assert mock_config_entry.state is ConfigEntryState.LOADED
 
 
+@pytest.mark.parametrize(
+    "exception",
+    [
+        pytest.param(DucoError("API error"), id="duco_error"),
+        pytest.param(DucoConnectionError("Connection refused"), id="connection_error"),
+    ],
+)
+async def test_setup_entry_recovers_from_optional_temperature_capability_failure(
+    hass: HomeAssistant,
+    freezer: FrozenDateTimeFactory,
+    mock_config_entry: MockConfigEntry,
+    mock_duco_client: AsyncMock,
+    exception: Exception,
+) -> None:
+    """Test an optional temperature capability is retried after a setup failure."""
+    mock_duco_client.async_get_ventilation_temperature_info.side_effect = [
+        exception,
+        VentilationTemperatureInfo(temp_oda=5.5),
+    ]
+    mock_config_entry.add_to_hass(hass)
+
+    await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert mock_config_entry.state is ConfigEntryState.LOADED
+    assert hass.states.get("sensor.living_outdoor_air_temperature") is None
+
+    freezer.tick(SCAN_INTERVAL)
+    async_fire_time_changed(hass)
+    await hass.async_block_till_done(wait_background_tasks=True)
+
+    state = hass.states.get("sensor.living_outdoor_air_temperature")
+    assert state is not None
+    assert state.state == "5.5"
+
+
 async def test_setup_entry_ignores_node_name_config_failures(
     hass: HomeAssistant,
     mock_config_entry: MockConfigEntry,
@@ -280,6 +318,9 @@ async def test_setup_entry_creates_http_client(
         mock_client_class.return_value.async_get_node_actions.return_value = (
             mock_node_actions
         )
+        (
+            mock_client_class.return_value.async_get_ventilation_temperature_info.return_value
+        ) = VentilationTemperatureInfo()
         mock_client_class.return_value.async_get_diagnostics.return_value = [
             DiagComponent(component="Ventilation", status="Ok")
         ]
diff --git a/tests/components/duco/test_sensor.py b/tests/components/duco/test_sensor.py
index 563ab57fb6b7..f3c978d0822b 100644
--- a/tests/components/duco/test_sensor.py
+++ b/tests/components/duco/test_sensor.py
@@ -7,12 +7,14 @@ from unittest.mock import AsyncMock
 from duco_connectivity import (
     DucoConnectionError,
     DucoError,
+    DucoUnsupportedCapabilityError,
     Node,
     NodeGeneralInfo,
     NodeSensorInfo,
     NodeType,
     NodeVentilationInfo,
     VentilationState,
+    VentilationTemperatureInfo,
 )
 from freezegun.api import FrozenDateTimeFactory
 import pytest
@@ -28,6 +30,12 @@ from . import setup_platform_integration
 from tests.common import MockConfigEntry, async_fire_time_changed, snapshot_platform
 
 FILTER_REMAINING_ENTITY_ID = "sensor.living_filter_remaining"
+VENTILATION_TEMPERATURE_ENTITY_IDS = (
+    "sensor.living_outdoor_air_temperature",
+    "sensor.living_supply_air_temperature",
+    "sensor.living_extract_air_temperature",
+    "sensor.living_exhaust_air_temperature",
+)
 
 
 @pytest.mark.parametrize(
@@ -223,6 +231,55 @@ async def test_time_filter_remaining_missing_skips_sensor_creation(
     assert hass.states.get(FILTER_REMAINING_ENTITY_ID) is None
 
 
+async def test_ventilation_temperatures_missing_skip_sensor_creation(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_duco_client: AsyncMock,
+    freezer: FrozenDateTimeFactory,
+) -> None:
+    """Test unsupported ventilation temperatures never expose temperature states."""
+    mock_duco_client.async_get_ventilation_temperature_info.side_effect = [
+        DucoUnsupportedCapabilityError(400, "/info", '{"Code":3,"Result":"FAILED"}'),
+        VentilationTemperatureInfo(temp_oda=5.5),
+    ]
+
+    await setup_platform_integration(hass, mock_config_entry, [Platform.SENSOR])
+
+    for entity_id in VENTILATION_TEMPERATURE_ENTITY_IDS:
+        assert hass.states.get(entity_id) is None
+
+    freezer.tick(SCAN_INTERVAL)
+    async_fire_time_changed(hass)
+    await hass.async_block_till_done(wait_background_tasks=True)
+
+    for entity_id in VENTILATION_TEMPERATURE_ENTITY_IDS:
+        assert hass.states.get(entity_id) is None
+
+
+async def test_partial_ventilation_temperatures_only_expose_available_sensor_values(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_duco_client: AsyncMock,
+) -> None:
+    """Test only populated ventilation temperature fields are exposed as states."""
+    mock_duco_client.async_get_ventilation_temperature_info.return_value = (
+        VentilationTemperatureInfo(temp_oda=5.5, temp_eta=21.4)
+    )
+
+    await setup_platform_integration(hass, mock_config_entry, [Platform.SENSOR])
+
+    state = hass.states.get("sensor.living_outdoor_air_temperature")
+    assert state is not None
+    assert state.state == "5.5"
+
+    state = hass.states.get("sensor.living_extract_air_temperature")
+    assert state is not None
+    assert state.state == "21.4"
+
+    assert hass.states.get("sensor.living_supply_air_temperature") is None
+    assert hass.states.get("sensor.living_exhaust_air_temperature") is None
+
+
 async def test_time_filter_remaining_transient_failure_recovers_sensor_creation(
     hass: HomeAssistant,
     mock_config_entry: MockConfigEntry,