Index: firmware/App/Modes/ModeStandby.c
===================================================================
diff -u -rf47dd3b39499eee03d3e93236335c087b4ad71fb -r16c791301d13ab6517185c84cb00db53fe16564b
--- firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision f47dd3b39499eee03d3e93236335c087b4ad71fb)
+++ firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision 16c791301d13ab6517185c84cb00db53fe16564b)
@@ -1156,6 +1156,7 @@
         getNVRecord2Driver( GET_USAGE_RECORD, (U08*)&usageRecord, sizeof( HD_USAGE_INFO_RECORD_T ), 0, ALARM_ID_NO_ALARM );
 
         U32 lastChemCompleteDateS      = data.dgUsageInfo.lastChemDisCompleteDateEpoch;
+        U32 lastChemStartDateS         = data.dgUsageInfo.lastChemDisStartDateEpoch;
         U32 lastChemFlushCompleteDateS = data.dgUsageInfo.lastChemDisFlushCompleteDateEpoch;
         U32 lastHeatCompleteDateS      = data.dgUsageInfo.lastHeatDisCompleteDateEpoch;
         U32 lastFlushCompleteDateS     = data.dgUsageInfo.lastBasicFlushCompleteDateEpoch;
@@ -1171,7 +1172,7 @@
         BOOL isHeatDisValid = ( ( currentRTCEpochTimeS - lastHeatCompleteDateS ) < DISINFECTS_TIME_INTERVAL_S ? TRUE : FALSE );
 
         // Last Chem Flush Complete < Last Chem Disinfect Start, so after running a chemical disinfect, a chemical disinfect flush has been done
-        BOOL isChemFlushComplete = ( lastChemFlushCompleteDateS > lastChemCompleteDateS ? TRUE : FALSE );
+        BOOL isChemFlushComplete = ( lastChemFlushCompleteDateS > lastChemStartDateS ? TRUE : FALSE );
 
         // If either of the basic flush, heat disinfect, or chemical disinfect flush have been done within the interval, it means the filters have been flushed
         BOOL isBasicFlushValid       = ( ( currentRTCEpochTimeS - lastFlushCompleteDateS     ) < FLUSH_TIME_INTERVAL_S ? TRUE : FALSE );