diff --git a/pytec/tec_qt.py b/pytec/tec_qt.py
index e5267f0..ba67911 100755
--- a/pytec/tec_qt.py
+++ b/pytec/tec_qt.py
@@ -191,21 +191,15 @@ class MainWindow(QtWidgets.QMainWindow):
                     )
                 )
                 self.thermostat.connection_state = ThermostatConnectionState.CONNECTING
-                try:
-                    await self._connecting_task
-                except (OSError, asyncio.CancelledError) as exc:
-                    await self.thermostat.end_session()
-                    if isinstance(exc, asyncio.CancelledError):
-                        return
-                    raise
-                finally:
-                    self._connecting_task = None
+                await self._connecting_task
+                self._connecting_task = None
                 self.thermostat.connection_state = ThermostatConnectionState.CONNECTED
                 self.thermostat.start_watching()
 
             case ThermostatConnectionState.CONNECTING:
                 self._connecting_task.cancel()
-                self.thermostat.connection_state = (
+                await self._thermostat.end_session()
+                self._thermostat.connection_state = (
                     ThermostatConnectionState.DISCONNECTED
                 )
                 self._connecting_task = None