diff --git a/tests/components/bsblan/conftest.py b/tests/components/bsblan/conftest.py
index c0aa40adbf2c21..331d7881a53f97 100644
--- a/tests/components/bsblan/conftest.py
+++ b/tests/components/bsblan/conftest.py
@@ -56,6 +56,14 @@ def mock_bsblan(request: pytest.FixtureRequest) -> Generator[MagicMock, None, No
         bsblan.static_values.return_value = StaticState.from_json(
             load_fixture(request.param, DOMAIN)
         )
+
+        # Add a method to update the current_temperature dynamically
+        def set_current_temperature(value):
+            state = bsblan.state.return_value
+            state.current_temperature.value = value
+
+        bsblan.set_current_temperature = set_current_temperature
+
         yield bsblan
 
 
diff --git a/tests/components/bsblan/test_climate.py b/tests/components/bsblan/test_climate.py
index 0c9524413e6a7c..cc738c06d4dd09 100644
--- a/tests/components/bsblan/test_climate.py
+++ b/tests/components/bsblan/test_climate.py
@@ -24,3 +24,15 @@ async def test_climate_entity(
     await setup_with_selected_platforms(hass, mock_config_entry, [Platform.CLIMATE])
 
     await snapshot_platform(hass, entity_registry, snapshot, mock_config_entry.entry_id)
+
+    # Spoof the current_temperature value to "---"
+    mock_bsblan.set_current_temperature("---")
+
+    # Update the state in Home Assistant
+    await hass.helpers.entity_component.async_update_entity("climate.bsb_lan")
+
+    # Get the state of the climate entity
+    state = hass.states.get("climate.bsb_lan")
+
+    # Assert that the current_temperature attribute is None
+    assert state.attributes["current_temperature"] is None