Index: firmware/App/Modes/ModeStandby.c
===================================================================
diff -u -r56ba1b163b0cbf6953638065b2108f745b17ec8f -re0413e662822f3ccc8b4fe9d969efef7eedb05ad
--- firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision 56ba1b163b0cbf6953638065b2108f745b17ec8f)
+++ firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision e0413e662822f3ccc8b4fe9d969efef7eedb05ad)
@@ -7,8 +7,8 @@
 *
 * @file    ModeStandby.c
 *
-* @author  (last)      Dara Navaei
-* @date    (last)      03-Feb-2023
+* @author  (last)      Michael Garthwaite
+* @date    (last)      01-Mar-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -200,12 +200,10 @@
     // if HD requests water sample, go to water sample state
     else if ( TRUE == flushFilterRequest )
     {
+        setValveState( VPI, VALVE_STATE_OPEN );
         flushFilterRequest   = FALSE;
         filterFlushStartTime = getMSTimerCount();
-
-        setValveState( VPI, VALVE_STATE_OPEN );
-
-        state = DG_STANDBY_MODE_STATE_FLUSH_FILTER;
+        state                = DG_STANDBY_MODE_STATE_FLUSH_FILTER;
     }
     else if ( TRUE == pendingStartDGRequest )
     {
@@ -270,7 +268,7 @@
         data.countdown = data.timeout - ( calcTimeSince( filterFlushStartTime ) / MS_PER_SECOND );
         filterFlushPublishTimerCounter = 0;
 
-        broadcastData( MSG_ID_DG_FILTER_FLUSH_PROGRESS, COMM_BUFFER_OUT_CAN_DG_BROADCAST, (U08*)&data, sizeof( STANDBY_MODE_DATA_T ) );
+        broadcastData( MSG_ID_DG_FILTER_FLUSH_PROGRESS_DATA, COMM_BUFFER_OUT_CAN_DG_BROADCAST, (U08*)&data, sizeof( STANDBY_MODE_DATA_T ) );
     }
 
     if ( TRUE == endSampleWaterRequest )
@@ -558,14 +556,14 @@
     {
         DG_CMD_RESPONSE_T cmdResponse;
         DG_USAGE_INFO_RECORD_T usageInfo;
+        OPN_CLS_STATE_T concCap = getSwitchStatus( CONCENTRATE_CAP );
+        OPN_CLS_STATE_T diaCap  = getSwitchStatus( DIALYSATE_CAP );
 
         getNVRecord2Driver( GET_USAGE_RECORD, (U08*)&usageInfo, sizeof( DG_USAGE_INFO_RECORD_T ), 0, ALARM_ID_NO_ALARM );
 
-        cmdResponse.commandID   = DG_CMD_START_HEAT_DISINFECT;
-        cmdResponse.rejected    = FALSE;
-        cmdResponse.rejectCode  = DG_CMD_REQUEST_REJECT_REASON_NONE;
-        OPN_CLS_STATE_T concCap = getSwitchStatus( CONCENTRATE_CAP );
-        OPN_CLS_STATE_T diaCap  = getSwitchStatus( DIALYSATE_CAP );
+        cmdResponse.commandID  = DG_CMD_START_HEAT_DISINFECT;
+        cmdResponse.rejected   = FALSE;
+        cmdResponse.rejectCode = DG_CMD_REQUEST_REJECT_REASON_NONE;
 
 #ifndef _RELEASE_
         if ( SW_CONFIG_ENABLE_VALUE == getSoftwareConfigStatus( SW_CONFIG_DISABLE_CAPS_MONITOR ) )
@@ -621,7 +619,7 @@
         cmdResponse.commandID  = DG_CMD_START_CHEM_DISINFECT;
         cmdResponse.rejected   = FALSE;
         cmdResponse.rejectCode = DG_CMD_REQUEST_REJECT_REASON_NONE;
-        OPN_CLS_STATE_T diaCap  = getSwitchStatus( DIALYSATE_CAP );
+        OPN_CLS_STATE_T diaCap = getSwitchStatus( DIALYSATE_CAP );
 
 #ifndef _RELEASE_
         if ( SW_CONFIG_ENABLE_VALUE == getSoftwareConfigStatus( SW_CONFIG_DISABLE_CAPS_MONITOR ) )
@@ -668,20 +666,22 @@
     // Chemical disinfect flush cannot be run in solo mode because the user has to confirm that the acid is inserted or removed
     if ( ( DG_MODE_STAN == getCurrentOperationMode() ) && ( DG_STANDBY_MODE_STATE_IDLE == standbyState ) )
     {
+        OPN_CLS_STATE_T concCap = getSwitchStatus( CONCENTRATE_CAP );
         OPN_CLS_STATE_T diaCap  = getSwitchStatus( DIALYSATE_CAP );
 
 #ifndef _RELEASE_
         if ( SW_CONFIG_ENABLE_VALUE == getSoftwareConfigStatus( SW_CONFIG_DISABLE_CAPS_MONITOR ) )
         {
+            concCap = STATE_CLOSED;
             diaCap  = STATE_CLOSED;
         }
 #endif
 
-        // When chemical disinfect flush is about to be started, dialysate cap must be closed
-        if ( STATE_OPEN == diaCap )
+        if ( ( STATE_OPEN == concCap ) || ( STATE_OPEN == diaCap ) )
         {
             cmdResponse.rejected   = TRUE;
-            cmdResponse.rejectCode = REQUEST_REJECT_REASON_DG_DIALYSATE_CAP_OPEN;
+            cmdResponse.rejectCode = ( STATE_OPEN == getSwitchStatus( DIALYSATE_CAP ) ? REQUEST_REJECT_REASON_DG_DIALYSATE_CAP_OPEN :
+                                                                                        REQUEST_REJECT_REASON_DG_CONCENTRATE_CAP_OPEN );
         }
         else
         {