Index: firmware/App/Modes/ModePostTreat.c
===================================================================
diff -u -raa7b1f5f68aae23c1c52b32658fcb625c29accfb -r4b17eafaab61aef5766ffd0c17769561bdbb159c
--- firmware/App/Modes/ModePostTreat.c	(.../ModePostTreat.c)	(revision aa7b1f5f68aae23c1c52b32658fcb625c29accfb)
+++ firmware/App/Modes/ModePostTreat.c	(.../ModePostTreat.c)	(revision 4b17eafaab61aef5766ffd0c17769561bdbb159c)
@@ -45,11 +45,14 @@
 
 /// Interval (ms/task time) at which the post-treatment state data is published on the CAN bus.
 #define POST_TREATMENT_DATA_PUB_INTERVAL        ( 250 / TASK_GENERAL_INTERVAL )
+#define DIP_DRAIN_DG_FLOW_RATE_ML_MIN           60                  ///< DG drain inlet pump flow rate in mL/min.
+#define DIP_DRAIN_DG_RUNTIME_MS                 20000               ///< DG drain inlet pump run time.
 
 /// Post-Treatment drain reservoirs state machine.
 typedef enum Drain_States
 {
-    DRAIN_RESERVOIR_SWITCH_STATE = 0,                               ///< Switch reservoir state.
+    DRAIN_DG_STATE = 0,                                             ///< Drain DG excess fluid state.
+    DRAIN_RESERVOIR_SWITCH_STATE,                                   ///< Switch reservoir state.
     DRAIN_RESERVOIR_START_DRAIN_STATE,                              ///< Drain reservoir start drain state.
     DRAIN_RESERVOIR_DRAIN_STATE,                                    ///< Drain first reservoir state.
     DRAIN_RESERVOIR_COMPLETE_STATE,                                 ///< Drain complete state.
@@ -78,6 +81,7 @@
 static HD_POST_TREATMENT_STATE_T handlePostTreatmentVerifyState( void );
 
 static void execDrainReservoirs( void );
+static DRAIN_STATE_T handleDrainDGState( void );
 static DRAIN_STATE_T handleDrainReservoirSwitchState( void );
 static DRAIN_STATE_T handleDrainReservoirStartDrainState( void );
 static DRAIN_STATE_T handleDrainReservoirDrainState( void );
@@ -98,7 +102,7 @@
     rinseConcentrateLines            = FALSE;
     isThisFirstDrain                 = TRUE;
     currentPostTreatmentState        = HD_POST_TREATMENT_DRAIN_RESERVOIRS_STATE;
-    currentDrainReservoirState       = DRAIN_RESERVOIR_SWITCH_STATE;
+    currentDrainReservoirState       = DRAIN_DG_STATE;  // DRAIN_RESERVOIR_SWITCH_STATE;
     postTreatmentPublishTimerCounter = 0;
 
     // Reset treatment log data
@@ -502,6 +506,10 @@
 {
     switch ( currentDrainReservoirState )
     {
+        case DRAIN_DG_STATE:
+            currentDrainReservoirState = handleDrainDGState();
+            break;
+
         case DRAIN_RESERVOIR_SWITCH_STATE:
             currentDrainReservoirState = handleDrainReservoirSwitchState();
             break;
@@ -526,6 +534,44 @@
 
 /*********************************************************************//**
  * @brief
+ * The handleDrainDGState function waits for DG to complete
+ * reservoir switch.
+ * @details Inputs:
+ * @details Outputs:
+ * @return next state
+ *************************************************************************/
+static DRAIN_STATE_T handleDrainDGState( void )
+{
+    static BOOL drain_dg_active = FALSE;
+    static U32 drain_dg_starttime = 0;
+    DRAIN_STATE_T state = DRAIN_DG_STATE;
+
+    if ( ( DG_MODE_GENE == getDGOpMode() ) && ( DG_GEN_IDLE_MODE_STATE_FLUSH_WATER == getDGSubMode() ) )
+    {
+        if ( FALSE == drain_dg_active )
+        {
+            // First entry - Run DPi slow reverse, VDi, VDo closed in init, DPo Off in init.
+            setDialInPumpTargetFlowRate( DIP_DRAIN_DG_FLOW_RATE_ML_MIN, MOTOR_DIR_REVERSE, PUMP_CONTROL_MODE_OPEN_LOOP );
+            drain_dg_starttime = getMSTimerCount();
+            drain_dg_active = TRUE;
+        }
+    }
+    if ( TRUE == drain_dg_active )
+    {
+        // Thereafter, check for time elapsed
+        if ( TRUE == didTimeout( drain_dg_starttime, DIP_DRAIN_DG_RUNTIME_MS ) )
+        {
+            drain_dg_active = FALSE;
+            setDialInPumpTargetFlowRate( 0, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
+            state = DRAIN_RESERVOIR_SWITCH_STATE;
+        }
+    }
+
+    return state;
+}
+
+/*********************************************************************//**
+ * @brief
  * The handleDrainReservoirSwitchState function waits for DG to complete
  * reservoir switch.
  * @details Inputs: isThisFirstDrain