diff --git a/FHEM/73_GasCalculator.pm b/FHEM/73_GasCalculator.pm
index c2b7e4550..e3fb91cf7 100644
--- a/FHEM/73_GasCalculator.pm
+++ b/FHEM/73_GasCalculator.pm
@@ -98,6 +98,7 @@ sub GasCalculator_Define($$$)
 	$hash->{REGEXP} = $RegEx;	
 
 	### Writing values to global hash
+	notifyRegexpChanged($hash, $RegEx);
 	$hash->{NAME}							= $name;
 	$hash->{STATE}              			= "active";
 	$hash->{REGEXP}             			= $RegEx;