diff --git a/fhem/fhem.pl b/fhem/fhem.pl
index 94e832c0b..6bae7512d 100755
--- a/fhem/fhem.pl
+++ b/fhem/fhem.pl
@@ -4183,6 +4183,7 @@ OldReadingsNum($$$;$)
   my $val = OldReadingsVal($d,$n,$default);
   return undef if(!defined($val));
   $val = ($val =~ /(-?\d+(\.\d+)?)/ ? $1 : "");
+  return $default if($val eq "");
   $val = round($val,$round) if($round);
   return $val;
 }
@@ -4229,6 +4230,7 @@ ReadingsNum($$$;$)
   my $val = ReadingsVal($d,$n,$default);
   return undef if(!defined($val));
   $val = ($val =~ /(-?\d+(\.\d+)?)/ ? $1 : "");
+  return $default if($val eq "");
   $val = round($val,$round) if($round);
   return $val;
 }