diff --git a/homeassistant/components/devialet/config_flow.py b/homeassistant/components/devialet/config_flow.py
index 6c394faaa53..41acfa4b5a7 100644
--- a/homeassistant/components/devialet/config_flow.py
+++ b/homeassistant/components/devialet/config_flow.py
@@ -23,12 +23,13 @@ class DevialetFlowHandler(ConfigFlow, domain=DOMAIN):
 
     VERSION = 1
 
+    _host: str
+    _model: str
+    _name: str
+    _serial: str
+
     def __init__(self) -> None:
         """Initialize flow."""
-        self._host: str | None = None
-        self._name: str | None = None
-        self._model: str | None = None
-        self._serial: str | None = None
         self._errors: dict[str, str] = {}
 
     async def async_validate_input(self) -> ConfigFlowResult | None: