diff --git a/pytec/tec_qt.py b/pytec/tec_qt.py
index 3d45c15..58ea46f 100755
--- a/pytec/tec_qt.py
+++ b/pytec/tec_qt.py
@@ -63,6 +63,7 @@ class MainWindow(QtWidgets.QMainWindow):
         self.info_box = InfoBox()
 
         self.thermostat = Thermostat(self, self.report_refresh_spin.value())
+        self._connecting_task = None
 
         def handle_connection_error():
             self.info_box.display_info_box(
@@ -231,38 +232,37 @@ class MainWindow(QtWidgets.QMainWindow):
 
     @asyncSlot()
     async def on_connect_btn_clicked(self):
-        host, port = (
-            self.conn_menu.host_set_line.text(),
-            self.conn_menu.port_set_spin.value(),
-        )
+        if (self._connecting_task is None) and (not self.thermostat.connected()):
+            self.status_lbl.setText("Connecting...")
+            self.connect_btn.setText("Stop")
+            self.conn_menu.host_set_line.setEnabled(False)
+            self.conn_menu.port_set_spin.setEnabled(False)
 
-        self._connecting_task = None
-        try:
-            if (self._connecting_task is None) or (not self.thermostat.connected()):
-                self.status_lbl.setText("Connecting...")
-                self.connect_btn.setText("Stop")
-                self.conn_menu.host_set_line.setEnabled(False)
-                self.conn_menu.port_set_spin.setEnabled(False)
-
-                try:
-                    self._connecting_task = asyncio.wait_for(
-                        self.thermostat.start_session(host=host, port=port), timeout=5
-                    )
-                    await self._connecting_task
-                except asyncio.TimeoutError:
-                    return
-                await self._on_connection_changed(True)
-            else:
-                if self._connecting_task is not None:
-                    self._connecting_task.cancel()
-                await self.bail()
-
-        # TODO: Remove asyncio.TimeoutError in Python 3.11
-        except (OSError, asyncio.TimeoutError):
+            self._connecting_task = asyncio.create_task(
+                asyncio.wait_for(
+                    self.thermostat.start_session(
+                        host=self.conn_menu.host_set_line.text(),
+                        port=self.conn_menu.port_set_spin.value(),
+                    ),
+                    timeout=5,
+                )
+            )
             try:
+                await self._connecting_task
+            except (OSError, asyncio.TimeoutError, asyncio.CancelledError) as exc:
                 await self.bail()
-            except ConnectionResetError:
-                pass
+                if isinstance(exc, asyncio.CancelledError):
+                    return
+                raise
+            else:
+                await self._on_connection_changed(True)
+            finally:
+                self._connecting_task = None
+
+        elif self._connecting_task is not None:
+            self._connecting_task.cancel()
+        else:
+            await self.bail()
 
     @asyncSlot()
     async def bail(self):