Update powerwall.sh

powerwall.sh

@@ -141,7 +141,7 @@ Shutting down system servers!!" 1
 						SENDNOTICE "${SENSOR} BACK TO NORMAL" "($datetime) NORMAL TEMP: ${temp_f}°F\nPrevious Temp: ${last_temp[${SENSOR}]}°F"
 						echo -e "($datetime) - ${SENSOR} - ${temp_f}'F - Back to NORMAL TEMP - Previous Temp: ${last_temp[${SENSOR}]}'F" >> ${logtemp}
 						echo "($datetime) - ${SENSOR} - ${temp_f}F - alert sent" >> ${logtemp}
-					elif [ $last_temp -eq 0 ]; then
+					elif [ ${last_temp[${SENSOR}]} -eq 0 ]; then
 						SENDNOTICE "${SENSOR} TEMP NORMAL" "($datetime) Service Startup\n NORMAL TEMP: ${temp_f}°F"
 						echo -e "($datetime) - ${SENSOR} - ${temp_f}'F - Service Startup - NORMAL TEMP" >> ${logtemp}
 					fi