diff --git a/fhem/CHANGED b/fhem/CHANGED
index 12ec5faaa..373586119 100644
--- a/fhem/CHANGED
+++ b/fhem/CHANGED
@@ -1,5 +1,6 @@
 # Add changes at the top of the list. Keep it in ASCII, and 80-char wide.
 # Do not insert empty lines here, update check depends on it.
+  - bugfix:  44_TEK603: Fixed TankLevel=NO_DATA 
   - feature: LGTV_IP12: new reading "power"
   - change:  LGTV_IP12: changed values of mute reading from true/false to on/off
   - bugfix:  30_MilightBridge: suppress protocol change message on startup
diff --git a/fhem/FHEM/44_TEK603.pm b/fhem/FHEM/44_TEK603.pm
index e8e5d08ef..2515eda5a 100644
--- a/fhem/FHEM/44_TEK603.pm
+++ b/fhem/FHEM/44_TEK603.pm
@@ -174,6 +174,8 @@ sub TEK603_read($) {
 	my $RemainingUsableLevel= hex(substr($payload,6,2)) * 256 + hex(substr($payload,8,2));
 	my $TotalUsableCapacity = hex(substr($payload,10,2)) * 256 + hex(substr($payload,12,2));
 
+	return '' if($temp eq "-40" && $Ullage eq "0"); # TankLevel=NO_DATA
+
 	#Log3 $name, 5, $hash->{buffer};
 	Log3 $name, 5, "Time:$time Temp:$temp Ullage:$Ullage RemainingUsableLevel:$RemainingUsableLevel TotalUsableCapacity:$TotalUsableCapacity"; 
 
@@ -214,12 +216,12 @@ sub TEK603_reconnect($) {
     It works in conjunction with a TEK653 Sonic transmitter mounted on the top of the tank.
 
 
-  <br />
+  <br /><br /><br />
   <b>Prerequisites</b><br>
-  The module requires the perl module Digest::CRC<br>
-  On a debian based system the module can be installed with<br>
+  The module requires the perl module Digest::CRC<br />
+  On a debian based system the module can be installed with<br />
   <code>
-  sudo apt-get install libdigest-crc-perl<br>
+  sudo apt-get install libdigest-crc-perl<br />
   </code>
   <br /><br />