diff --git a/homeassistant/components/generic_thermostat/climate.py b/homeassistant/components/generic_thermostat/climate.py
index 76e8285f1ed5..2ec4c42cc9e2 100644
--- a/homeassistant/components/generic_thermostat/climate.py
+++ b/homeassistant/components/generic_thermostat/climate.py
@@ -51,6 +51,7 @@ from homeassistant.core import (
 )
 from homeassistant.helpers import config_validation as cv
 from homeassistant.helpers.device import async_entity_id_to_device
+from homeassistant.helpers.device_registry import DeviceEntry
 from homeassistant.helpers.entity import CONTEXT_RECENT_TIME_SECONDS
 from homeassistant.helpers.entity_platform import (
     AddConfigEntryEntitiesCallback,
@@ -143,6 +144,7 @@ async def async_setup_entry(
         PLATFORM_SCHEMA_COMMON(dict(config_entry.options)),
         config_entry.entry_id,
         async_add_entities,
+        device=async_entity_id_to_device(hass, config_entry.options[CONF_HEATER]),
     )
 
 
@@ -165,6 +167,7 @@ async def _async_setup_config(
     config: Mapping[str, Any],
     unique_id: str | None,
     async_add_entities: AddEntitiesCallback | AddConfigEntryEntitiesCallback,
+    device: DeviceEntry | None = None,
 ) -> None:
     """Set up the generic thermostat platform."""
 
@@ -192,7 +195,6 @@ async def _async_setup_config(
     async_add_entities(
         [
             GenericThermostat(
-                hass,
                 name=name,
                 heater_entity_id=heater_entity_id,
                 sensor_entity_id=sensor_entity_id,
@@ -212,6 +214,7 @@ async def _async_setup_config(
                 target_temperature_step=target_temperature_step,
                 unit=unit,
                 unique_id=unique_id,
+                device=device,
             )
         ]
     )
@@ -224,7 +227,6 @@ class GenericThermostat(ClimateEntity, RestoreEntity):
 
     def __init__(
         self,
-        hass: HomeAssistant,
         *,
         name: str,
         heater_entity_id: str,
@@ -245,15 +247,13 @@ class GenericThermostat(ClimateEntity, RestoreEntity):
         target_temperature_step: float | None,
         unit: UnitOfTemperature,
         unique_id: str | None,
+        device: DeviceEntry | None = None,
     ) -> None:
         """Initialize the thermostat."""
         self._attr_name = name
         self.heater_entity_id = heater_entity_id
         self.sensor_entity_id = sensor_entity_id
-        self.device_entry = async_entity_id_to_device(
-            hass,
-            heater_entity_id,
-        )
+        self.device_entry = device
         self.ac_mode = ac_mode
         self.min_cycle_duration = min_cycle_duration or timedelta()
         self.max_cycle_duration = max_cycle_duration
diff --git a/tests/components/generic_thermostat/test_climate.py b/tests/components/generic_thermostat/test_climate.py
index 2ec5681f1c7e..8b5072931bca 100644
--- a/tests/components/generic_thermostat/test_climate.py
+++ b/tests/components/generic_thermostat/test_climate.py
@@ -1873,6 +1873,50 @@ async def test_device_id(
     assert helper_entity.device_id == source_entity.device_id
 
 
+async def test_device_id_yaml(
+    hass: HomeAssistant,
+    entity_registry: er.EntityRegistry,
+    device_registry: dr.DeviceRegistry,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Test no device is set for a YAML-configured thermostat."""
+    source_config_entry = MockConfigEntry()
+    source_config_entry.add_to_hass(hass)
+    source_device_entry = device_registry.async_get_or_create(
+        config_entry_id=source_config_entry.entry_id,
+        identifiers={("switch", "identifier_test")},
+        connections={("mac", "30:31:32:33:34:35")},
+    )
+    entity_registry.async_get_or_create(
+        "switch",
+        "test",
+        "source",
+        config_entry=source_config_entry,
+        device_id=source_device_entry.id,
+    )
+    await hass.async_block_till_done()
+
+    assert await async_setup_component(
+        hass,
+        CLIMATE_DOMAIN,
+        {
+            "climate": {
+                "platform": "generic_thermostat",
+                "name": "test",
+                "heater": "switch.test_source",
+                "target_sensor": ENT_SENSOR,
+                "unique_id": "generic_thermostat_yaml",
+            }
+        },
+    )
+    await hass.async_block_till_done()
+
+    helper_entity = entity_registry.async_get("climate.test")
+    assert helper_entity is not None
+    assert helper_entity.device_id is None
+    assert "attempts to attach a device to an entity" not in caplog.text
+
+
 @pytest.mark.usefixtures("setup_comp_1")
 async def test_hvac_mode_change_user_context(
     hass: HomeAssistant, hass_admin_user: MockUser