Index: firmware/App/Modes/ModeStandby.c
===================================================================
diff -u -rfebf34ac531641da5c58262c56d3be6aeff3b209 -rcd5be724d5a3ba7457e761191d82f278654d7f5c
--- firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision febf34ac531641da5c58262c56d3be6aeff3b209)
+++ firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision cd5be724d5a3ba7457e761191d82f278654d7f5c)
@@ -1,14 +1,14 @@
 /**************************************************************************
 *
-* Copyright (c) 2019-2023 Diality Inc. - All Rights Reserved.
+* Copyright (c) 2019-2024 Diality Inc. - All Rights Reserved.
 *
 * THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
 * WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
 *
 * @file    ModeStandby.c
 *
-* @author  (last)      Sean Nash
-* @date    (last)      31-May-2023
+* @author  (last)      Dara Navaei
+* @date    (last)      10-Nov-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -49,7 +49,7 @@
 
 #define DISINFECTS_DATA_PUB_INTERVAL          ( 1 * MS_PER_SECOND / TASK_GENERAL_INTERVAL )    ///< Disinfects data publish interval in counts.
 #define DISINFECTS_TIME_INTERVAL_S            ( 3 * SECONDS_IN_A_DAY )                         ///< HD/DG 3-day service interval in seconds.
-#define FLUSH_TIME_INTERVAL_S                 ( 30 * SEC_PER_MIN )                             ///< Flush time interval in seconds.
+#define FLUSH_TIME_INTERVAL_S                 ( 2 * MIN_PER_HOUR * SEC_PER_MIN )               ///< Flush time interval in seconds.
 #define MAX_ALLOWED_RO_FILTER_TEMP_FOR_TX_C   44.0F                                            ///< Maximum allowed temperature to start a treatment in C.
 
 /// DG cleaning mode status data structure
@@ -70,6 +70,7 @@
 static BOOL treatStartReqReceived;                                                             ///< Flag indicates user has requested initiation of a treatment.
 static GENERIC_CONFIRM_ID_T disinfectCancelReqID;                                              ///< ID of requested cancel disinfect mode.
 static BOOL homingInitiated;                                                                   ///< Boolean flag to indicate homing is initiated.
+static BOOL flagNoDisinfectRequired = FALSE;                                                   ///< Flag indicates disinfect not required on next mode entry.
 static DG_CLEANING_MODE_STATUS_T currentDGCleaningMode;                                        ///< Current DG cleaning mode status.
 
 /// Interval (in task intervals) at which to publish standby mode data to CAN bus.
@@ -152,13 +153,14 @@
     setValvePosition( VBV, VALVE_POSITION_A_INSERT_EJECT );
 
     // If we just exited Post Treatment Mode, goto disinfect sub state.
-    if ( MODE_POST == previousOpMode )
+    if ( ( MODE_POST == previousOpMode ) && ( flagNoDisinfectRequired != TRUE ) )
     {
         doorClosedRequired( FALSE, FALSE );             // door no longer required to be closed in standby mode
         currentStandbyState = STANDBY_WAIT_FOR_DISINFECT_STATE;
     }
     else
     {
+        flagNoDisinfectRequired = FALSE;
         doorClosedRequired( TRUE, FALSE );
     }
     syringeDetectionRequired( FALSE );
@@ -307,6 +309,19 @@
 
 /*********************************************************************//**
  * @brief
+ * The signalNoDisinfectRequired function signals the standby mode module
+ * that a disinfection will not be required on next entry to standby mode.
+ * @details Inputs: none
+ * @details Outputs: flagNoDisinfectRequired
+ * @return none
+ *************************************************************************/
+void signalNoDisinfectRequired( void )
+{
+    flagNoDisinfectRequired = TRUE;
+}
+
+/*********************************************************************//**
+ * @brief
  * The signalAlarmActionToStandbyMode function executes the given alarm action
  * as appropriate while in Standby Mode.
  * @details Inputs: none
@@ -639,7 +654,7 @@
             else
 #endif
             {
-                if ( ( TRUE == homingInitiated ) && ( TRUE == isSyringePumpHome() ) && ( TRUE == isSyringePumpStopped() ) )
+                if ( ( TRUE == isSyringePumpHome() ) && ( TRUE == isSyringePumpStopped() ) )
                 {
                     syringePumpVerifyForceSensorDACCalibration();
                     homingInitiated = FALSE;                        // reset for next time
@@ -1141,6 +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;
@@ -1156,13 +1172,15 @@
         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 );
         BOOL isChemFlushValid        = ( ( currentRTCEpochTimeS - lastChemFlushCompleteDateS ) < FLUSH_TIME_INTERVAL_S ? TRUE : FALSE );
         BOOL isHeatDisCoolFlushValid = ( ( currentRTCEpochTimeS - lastHeatCoolCompleteDateS  ) < FLUSH_TIME_INTERVAL_S ? TRUE : FALSE );
-        BOOL isFlushValid            = ( ( TRUE == isBasicFlushValid ) || ( TRUE == isChemFlushValid ) || ( TRUE == isHeatDisCoolFlushValid ) ? TRUE : FALSE );
+        BOOL isHeatDisFlushValid     = ( ( currentRTCEpochTimeS - lastHeatCompleteDateS      ) < FLUSH_TIME_INTERVAL_S ? TRUE : FALSE );
+        BOOL isFlushValid            = ( ( ( TRUE == isBasicFlushValid ) || ( TRUE == isChemFlushValid ) || ( TRUE == isHeatDisCoolFlushValid ) ||
+                                           ( TRUE == isHeatDisFlushValid ) ) ? TRUE : FALSE );
 
         // If all of the above conditions are true, it means we can start a treatment
         if ( ( TRUE == hasDisBeenDone ) && ( TRUE == isHeatDisValid ) && ( TRUE == isChemFlushComplete ) && ( TRUE == isFlushValid ) )