Update homeassistant/components/flexit_bacnet/climate.py

Co-authored-by: Copilot <[email protected]>

Author: magnusoverli

homeassistant/components/flexit_bacnet/climate.py

@@ -141,7 +141,15 @@ async def async_set_preset_mode(self, preset_mode: str) -> None:
                 await self.device.trigger_fireplace_mode()
             else:
                 # Use ventilation mode for standard modes
-                ventilation_mode = PRESET_TO_VENTILATION_MODE_MAP[preset_mode]
+                ventilation_mode = PRESET_TO_VENTILATION_MODE_MAP.get(preset_mode)
+                if ventilation_mode is None:
+                    raise HomeAssistantError(
+                        translation_domain=DOMAIN,
+                        translation_key="invalid_preset_mode",
+                        translation_placeholders={
+                            "preset": preset_mode,
+                        },
+                    )
                 await self.device.set_ventilation_mode(ventilation_mode)
         except (asyncio.exceptions.TimeoutError, ConnectionError, DecodingError) as exc:
             raise HomeAssistantError(