diff --git a/pytec/tec_qt.py b/pytec/tec_qt.py
index d3675c8..257d375 100644
--- a/pytec/tec_qt.py
+++ b/pytec/tec_qt.py
@@ -216,11 +216,11 @@ class ChannelGraphs:
             self._t_line.setVisible(visible)
         if temp is not None:
             self._t_line.setValue(temp)
-            if visible is False:
-                # PyQtGraph does not update this text when the line
-                # is not visible, but we need it so that the temperature
-                # label doesn't display 0 °C despite not being at 0 °C.
-                self._t_line.label.setText(f"{temp} °C")
+
+            # PyQtGraph normally does not update this text when the line
+            # is not visible, so make sure that the temperature label 
+            # gets updated always, and doesn't stay at an old value.
+            self._t_line.label.setText(f"{temp} °C")
 
 
 class MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):