Index: firmware/App/Modes/ModeHeatDisinfect.c
===================================================================
diff -u -r7cc77947d23e4be589753ea3bae781a5e15cc898 -rd28018ec9af4486c787c4205257ad2cf68da8cfd
--- firmware/App/Modes/ModeHeatDisinfect.c	(.../ModeHeatDisinfect.c)	(revision 7cc77947d23e4be589753ea3bae781a5e15cc898)
+++ firmware/App/Modes/ModeHeatDisinfect.c	(.../ModeHeatDisinfect.c)	(revision d28018ec9af4486c787c4205257ad2cf68da8cfd)
@@ -7,8 +7,8 @@
 *
 * @file    ModeHeatDisinfect.c
 *
-* @author  (last)      Bill Bracken
-* @date    (last)      26-Oct-2022
+* @author  (last)      Dara Navaei
+* @date    (last)      28-Oct-2022
 *
 * @author  (original)  Sean
 * @date    (original)  20-Apr-2020
@@ -533,7 +533,7 @@
 
             // Done with final draining
             isThisLastDrain = FALSE;
-            state = DG_HEAT_DISINFECT_STATE_RINSE_CIRCULATION;
+            state           = DG_HEAT_DISINFECT_STATE_RINSE_CIRCULATION;
         }
         else
         {
@@ -551,8 +551,6 @@
             state = DG_HEAT_DISINFECT_STATE_DRAIN_R2;
         }
 
-        setValveState( VPO, VALVE_STATE_FILL_C_TO_NC);
-
         // Start the timer
         stateTimer = getMSTimerCount();
     }
@@ -590,8 +588,9 @@
         {
             setValveState( VRD1, VALVE_STATE_OPEN );
             setValveState( VRD2, VALVE_STATE_CLOSED );
+
             rsrvr1Status = DG_RESERVOIR_ABOVE_TARGET;
-            state = DG_HEAT_DISINFECT_STATE_DRAIN_R1;
+            state        = DG_HEAT_DISINFECT_STATE_DRAIN_R1;
         }
         else
         {
@@ -603,16 +602,17 @@
             // Done with draining R2, close it
             setValveState( VRD2, VALVE_STATE_CLOSED );
             setValveState( VPI, VALVE_STATE_OPEN );
+            setValveState( VPO, VALVE_STATE_NOFILL_C_TO_NO );
+
             stateTrialCounter = 0;
-            stateTimer = getMSTimerCount();
-            state = DG_HEAT_DISINFECT_STATE_FLUSH_DRAIN;
+            stateTimer        = getMSTimerCount();
+            state             = DG_HEAT_DISINFECT_STATE_FLUSH_DRAIN;
         }
-        setValveState( VPO, VALVE_STATE_NOFILL_C_TO_NO );
     }
     else if ( DG_RESERVOIR_NOT_REACHED_TARGET == rsrvr2Status )
     {
         prevHeatDisinfectState = state;
-        state = DG_HEAT_DISINFECT_STATE_CANCEL_BASIC_PATH;
+        state                  = DG_HEAT_DISINFECT_STATE_CANCEL_BASIC_PATH;
     }
 
     return state;
@@ -1147,6 +1147,9 @@
             // Set the drain pump to control mode
             setDrainPumpTargetOutletPressure( HEAT_DISINFECT_TARGET_DRAIN_FILL_R2_PSI );
 
+            // Turn off trimmer heater for transition
+            stopHeater(DG_TRIMMER_HEATER);
+
             // Although there is fluid in both reservoirs, but they are set to empty
             // to begin the transition of hot water from R1 to R2.
             rsrvr2Status            = DG_RESERVOIR_BELOW_TARGET;
@@ -1210,6 +1213,10 @@
             // at inlet temperature > 45 C
             setROPumpTargetFlowRateLPM( HEAT_DISINFECT_TARGET_RO_FLOW_LPM, HEAT_DISINFECT_MAX_RO_PRESSURE_PSI );
 
+            // Start the trimmer heater since we are recirculating water and there is flow in the shunt line
+            setHeaterTargetTemperature( DG_TRIMMER_HEATER, HEAT_DISINFECT_TARGET_TEMPERATURE_C );
+            startHeater( DG_TRIMMER_HEATER );
+
             state = DG_HEAT_DISINFECT_STATE_DISINFECT_R2_TO_R1;
         }
         else if ( DG_RESERVOIR_NOT_REACHED_TARGET == rsrvr2Status )