Index: firmware/App/Controllers/BalancingChamber.c
===================================================================
diff -u -r5422509f9d8db102b62952ba9f5923e832d6b2fa -r9e6e86f604c8cce7c1704ae55d1e026de3422782
--- firmware/App/Controllers/BalancingChamber.c	(.../BalancingChamber.c)	(revision 5422509f9d8db102b62952ba9f5923e832d6b2fa)
+++ firmware/App/Controllers/BalancingChamber.c	(.../BalancingChamber.c)	(revision 9e6e86f604c8cce7c1704ae55d1e026de3422782)
@@ -20,6 +20,7 @@
 #include "ConcentratePumps.h"
 #include "DialysatePumps.h"
 #include "FpgaDD.h"
+#include "Heaters.h"
 #include "ModeStandby.h"
 #include "Messaging.h"
 #include "OperationModes.h"
@@ -37,7 +38,6 @@
 
 // ********** private definitions **********
 
-#define BAL_CHAMBER_FILL_VOLUME_ML                  30.0F                                       ///< Balancing chamber fill/drain volume per batch operation.
 #define BAL_CHAMBER_DATA_PUBLISH_INTERVAL           ( 250 / TASK_GENERAL_INTERVAL )             ///< Interval (ms/task time) at which the balancing chamber data published.
 
 /// Payload record structure for balancing chamber switch only request
@@ -63,6 +63,7 @@
 static BOOL balanceChamberSwitchingOnly;                                                        ///< Balancing chamber switching without any pressure check and dosing delivery.
 static OVERRIDE_F32_T acidDoseVolume;                                                           ///< Acid concentrate volume in ml ( overrideable).
 static OVERRIDE_F32_T bicarbDoseVolume;                                                         ///< Bicarb concentrate volume in ml ( overrideable).
+static F32 lastTdDialysateFlowrate;                                                             ///< Previous TD dialysate flow rate
 
 // ********** private function prototypes **********
 
@@ -107,6 +108,7 @@
     isBalChamberFillInProgress                  = FALSE;
     currentBalChamberSwitchingCounter           = 0;
     isPressureStalbilizedDuringFill             = FALSE;
+    lastTdDialysateFlowrate                     = 0.0F;
     balChamberDataPublicationTimerCounter       = 0;
 }
 
@@ -134,18 +136,29 @@
  *************************************************************************/
 void updateBalChamberSwitchingPeriod( void )
 {
-    // update the balancing chamber switching frequency
-    balChamberSwitchingFreq.data = getTDDialysateFlowrate() / BAL_CHAMBER_FILL_VOLUME_ML;
+    F32 tdDialysateFlowrate = getTDDialysateFlowrate();
 
-    //update the switching period in task interval for balancing chamber fill timeout check
-    balChamberSwitchingPeriod = (U32)( (F32)SEC_PER_MIN / getBalChamberSwitchingFreq() * ( MS_PER_SECOND / TASK_GENERAL_INTERVAL ) );
+    if ( lastTdDialysateFlowrate != tdDialysateFlowrate )
+    {
+        // update the balancing chamber switching frequency
+        balChamberSwitchingFreq.data = tdDialysateFlowrate / BAL_CHAMBER_FILL_VOLUME_ML;
 
-    // finish the balancing chamber fill 50 ms prior completing the regular cycle time.
-    balChamberSwitchingPeriod -= 1;
+        //update the switching period in task interval for balancing chamber fill timeout check
+        balChamberSwitchingPeriod = (U32)( (F32)SEC_PER_MIN / getBalChamberSwitchingFreq() * ( MS_PER_SECOND / TASK_GENERAL_INTERVAL ) );
 
-    //Testing
-    balChamberValveClosePeriod = balChamberSwitchingPeriod;
-    balChamberValveClosePeriod -= 1;   // Close valves prior 50 msecond for testing
+        // finish the balancing chamber fill 50 ms prior completing the regular cycle time.
+        balChamberSwitchingPeriod -= 1;
+
+        //Update last td dialysate flow rate
+        lastTdDialysateFlowrate = tdDialysateFlowrate;
+
+        //Update heater control on dialysate flow change
+        signalHeaterControlOnQDUpdate( D5_HEAT );
+
+        //Testing
+        balChamberValveClosePeriod = balChamberSwitchingPeriod;
+        balChamberValveClosePeriod -= 1;   // Close valves prior 50 msecond for testing
+    }
 }
 
 /*********************************************************************//**
@@ -404,8 +417,10 @@
     }
     else
     {
+#ifdef ENABLE_ALARM_2
         //Alarm when pressure is not in range
         SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DD_BC_STATE1_FILL_START_PRESSURE_OUT_OF_RANGE, freshDialPressure, spentDialPressure );
+#endif
     }
 
     return state;
@@ -433,10 +448,11 @@
     }
 
     // On dosing completion, transition to next state based on the current switching state
-    if ( ( ( TRUE == isConcentratePumpDosingCompleted( D11_PUMP ) ) &&
-           ( TRUE == isConcentratePumpDosingCompleted( D10_PUMP ) ) ) ||
-         ( TRUE == getBalChamberSwitchingOnlyStatus() ) )
-    {
+    // TODO : Need an updated FPGA to perform this check. For now commenting this check.
+//    if ( ( ( TRUE == isConcentratePumpDosingCompleted( D11_PUMP ) ) &&
+//           ( TRUE == isConcentratePumpDosingCompleted( D10_PUMP ) ) ) ||
+//         ( TRUE == getBalChamberSwitchingOnlyStatus() ) )
+//    {
         if ( BAL_CHAMBER_SW_STATE1 == balChamberSWState )
         {
             state = BAL_CHAMBER_STATE1_FILL_END;
@@ -445,7 +461,7 @@
         {
             state = BAL_CHAMBER_STATE2_FILL_END;
         }
-    }
+//    }
 
     return state;
 }
@@ -497,13 +513,17 @@
         {
             if ( TRUE != isPressureDroppedDuringFill )
             {
+#ifdef ENABLE_ALARM_2
                 // When fill initiated, pressure is not dropped to the expected range, possible valve failures.
                 SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DD_BC_STATE1_FILL_PRESSURE_DROP_OUT_OF_RANGE, freshDialPressure, spentDialPressure );
+#endif
             }
             else if ( TRUE != isPressureStalbilizedDuringFill )
             {
+#ifdef ENABLE_ALARM_2
                 // Alarm when switching time expired, but still pressure not in range which indicates fill is not yet completed.
                 SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DD_BC_STATE1_FILL_END_PRESSURE_OUT_OF_RANGE, freshDialPressure, spentDialPressure );
+#endif
             }
             else
             {
@@ -574,8 +594,10 @@
     }
     else
     {
+#ifdef ENABLE_ALARM_2
         //Alarm when pressure is not in range
         SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DD_BC_STATE2_FILL_START_PRESSURE_OUT_OF_RANGE, freshDialPressure, spentDialPressure );
+#endif
     }
     return state;
 }
@@ -628,13 +650,17 @@
         {
             if ( TRUE != isPressureDroppedDuringFill )
             {
+#ifdef ENABLE_ALARM_2
                 // When fill initiated, pressure is not dropped to the expected range, possible valve failures.
                 SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DD_BC_STATE2_FILL_PRESSURE_DROP_OUT_OF_RANGE, freshDialPressure, spentDialPressure );
+#endif
             }
             else if ( TRUE != isPressureStalbilizedDuringFill )
             {
+#ifdef ENABLE_ALARM_2
                 // Alarm when switching time expired, but still pressure not in range which indicates fill is not completed.
                 SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DD_BC_STATE2_FILL_END_PRESSURE_OUT_OF_RANGE, freshDialPressure, spentDialPressure );
+#endif
             }
             else
             {