Update temp.inc.sh

inc/temp.inc.sh

@@ -593,7 +593,7 @@ Previous Temp: ${last_temp[${SENSOR//-/}]}${GAUGESH}"
 										# (( $(bc <<<"${temp_difference} < 0") )) && temp_difference=`echo "scale=2; ${temp_difference} * -1" | bc`
 										echo "$(date "+%Y-%m-%d %H:%M:%S")~${temp_difference}" >> ${PW_TMPFOLDER}/.log.sr.difference
 									else
-										echo
+										echo 0
 									fi
 								fi
 							elif [ "${SENSOR}" == "ServerRoomTH" ]; then