diff --git a/Information/HeatTransfer/Components/Demo_vertical_opening_thermal_mode.tex b/Information/HeatTransfer/Components/Demo_vertical_opening_thermal_mode.tex
index 1d80e357271509b362fb349353bcdd919e753da4..01425b15730969d4fbda700cda9647d0cb8819f5 100644
--- a/Information/HeatTransfer/Components/Demo_vertical_opening_thermal_mode.tex
+++ b/Information/HeatTransfer/Components/Demo_vertical_opening_thermal_mode.tex
@@ -14,7 +14,7 @@
 \begin{document}
     \maketitle
     
-    \section{$\frac{-H}{2} \leq z \leq \frac{-H}{2} $}
+    \section{$\frac{-H}{2} \leq z \leq \frac{H}{2} $}
     
         \subsection{Mass flow rate from buoyancy calculation}