Index: firmware/App/Modes/ModeStandby.c
===================================================================
diff -u -r5d3e28c19ae10a99a5ce1fc5c010ac944975a6a1 -receb190a5d66fdbee779478ac8bb50a846ed9241
--- firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision 5d3e28c19ae10a99a5ce1fc5c010ac944975a6a1)
+++ firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision eceb190a5d66fdbee779478ac8bb50a846ed9241)
@@ -8,7 +8,7 @@
 * @file    ModeStandby.c
 *
 * @author  (last)      Dara Navaei
-* @date    (last)      27-Sep-2022
+* @date    (last)      21-Dec-2022
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -62,6 +62,7 @@
 static BOOL pendingStartDGHeatDisinfectRequest;                                         ///< Flag indicating HD has requested DG start heat disinfect.
 static BOOL pendingStartDGChemicalDisinfectRequest;                                     ///< Flag indicating HD has requested DG start chemical disinfect.
 static BOOL pendingStartDGHeatDisinfectActiveCoolRequest;                               ///< Flag indicating HD has requested DG start heat disinfect active cool.
+static BOOL pendingStartDGChemicalDisinfectFlushRequest;                                ///< Flag indicating HD has requested DG start chemical disinfect flush.
 
 static OVERRIDE_U32_T filterFlushTimePeriod = { FILTER_FLUSH_TIME_MS,
                                                 FILTER_FLUSH_TIME_MS, 0, 0 };           ///< Filter flush time period in ms.
@@ -203,19 +204,16 @@
     else if ( TRUE == pendingStartDGFlushRequest )
     {
         pendingStartDGFlushRequest = FALSE;
-
         requestNewOperationMode( DG_MODE_FLUS );
     }
     else if ( TRUE == pendingStartDGHeatDisinfectRequest )
     {
         pendingStartDGHeatDisinfectRequest = FALSE;
-
         requestNewOperationMode( DG_MODE_HEAT );
     }
     else if ( TRUE == pendingStartDGChemicalDisinfectRequest )
     {
         pendingStartDGChemicalDisinfectRequest = FALSE;
-
         requestNewOperationMode( DG_MODE_CHEM );
     }
     else if ( TRUE == pendingStartDGHeatDisinfectActiveCoolRequest )
@@ -224,6 +222,11 @@
 
         requestNewOperationMode( DG_MODE_HCOL );
     }
+    else if ( TRUE == pendingStartDGChemicalDisinfectFlushRequest )
+    {
+        pendingStartDGChemicalDisinfectFlushRequest = FALSE;
+        requestNewOperationMode( DG_MODE_CHFL );
+    }
 
     return state;
 }
@@ -319,6 +322,7 @@
     {
         stopSampleWaterRequest = FALSE;
         setValveState( VSP, VALVE_STATE_CLOSED );
+        setValveState( VPI, VALVE_STATE_CLOSED );
         state = DG_STANDBY_MODE_STATE_FLUSH_FILTER_IDLE;
     }
 
@@ -639,6 +643,61 @@
 
 /*********************************************************************//**
  * @brief
+ * The startDGChemicalDisinfectFlush function starts chemical disinfect flush mode.
+ * @details Inputs: standbyState
+ * @details Outputs: none
+ * @return: TRUE if the switch was successful
+ *************************************************************************/
+BOOL startDGChemicalDisinfectFlush( void )
+{
+    BOOL status = FALSE;
+    DG_CMD_RESPONSE_T cmdResponse;
+
+    cmdResponse.commandID  = DG_CMD_START_CHEM_DISINFECT_FLUSH;
+    cmdResponse.rejected   = FALSE;
+    cmdResponse.rejectCode = DG_CMD_REQUEST_REJECT_REASON_NONE;
+
+    // If DG is in standby mode and the standby mode is in Idle, request chemical disinfect flush
+    // 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, both caps must be closed
+        if ( ( STATE_OPEN == concCap ) || ( STATE_OPEN == diaCap ) )
+        {
+            cmdResponse.rejected   = TRUE;
+            cmdResponse.rejectCode = ( STATE_OPEN == getSwitchStatus( DIALYSATE_CAP ) ? REQUEST_REJECT_REASON_DG_DIALYSATE_CAP_OPEN :
+                                                                                        REQUEST_REJECT_REASON_DG_CONCENTRATE_CAP_OPEN );
+        }
+        else
+        {
+            pendingStartDGChemicalDisinfectFlushRequest = TRUE;
+            status                                      = TRUE;
+        }
+    }
+    else
+    {
+        cmdResponse.rejected   = TRUE;
+        cmdResponse.rejectCode = REQUEST_REJECT_REASON_DG_NOT_IN_STANDBY_IDLE_STATE;
+    }
+
+    sendCommandResponseMsg( &cmdResponse );
+
+    return status;
+}
+
+/*********************************************************************//**
+ * @brief
  * The getCurrentStandbyState function returns the current state of standby mode.
  * @details Inputs: standbyState
  * @details Outputs: none