diff --git a/doc/configuration.html b/doc/configuration.html
index 2cee328a..ca3f55f8 100644
--- a/doc/configuration.html
+++ b/doc/configuration.html
@@ -217,7 +217,7 @@ A screen can have the following options:
     Example:
 <pre>
     section: options
-        heatbeat = 5000
+        heartbeat = 5000
         switchDelay = 500
     end
 </pre>