Index: firmware/App/Modes/ModeFill.c
===================================================================
diff -u -r16cd633e1d18224face6f977120ccab3846e7671 -r945dcc1391faefe5f4ddb4f505361501d008e293
--- firmware/App/Modes/ModeFill.c	(.../ModeFill.c)	(revision 16cd633e1d18224face6f977120ccab3846e7671)
+++ firmware/App/Modes/ModeFill.c	(.../ModeFill.c)	(revision 945dcc1391faefe5f4ddb4f505361501d008e293)
@@ -202,7 +202,7 @@
 static DG_FILL_MODE_STATE_T handleDeliverDialysateState( void )
 {
     DG_FILL_MODE_STATE_T result = DG_FILL_MODE_STATE_DELIVER_DIALYSATE;
-    LOAD_CELL_ID_T fillWeightLoadCell = LOAD_CELL_A1;
+    RESERVOIR_ID_T inactiveReservoir = getInactiveReservoir();
 
     handleDialysateMixing();
     checkConcentrateConductivity();
@@ -220,14 +220,8 @@
         result = DG_FILL_MODE_STATE_DIALYSATE_PRODUCTION;
     }
 
-    // determine which load cell to use for fill volume - we want weight of inactive reservoir
-    if ( RESERVOIR_1 == getActiveReservoir() )
-    {
-        fillWeightLoadCell = LOAD_CELL_B1;
-    }
-
     // if we've reached our target fill to volume (by weight), we're done filling - go back to re-circ mode
-    if ( getReservoirFillVolumeTargetMl() <= getLoadCellFilteredWeight( fillWeightLoadCell ) )
+    if ( hasTargetFillVolumeReached( inactiveReservoir ) )
     {
         requestConcentratePumpOff();
         requestNewOperationMode( DG_MODE_CIRC );
Index: firmware/App/Services/Reservoirs.c
===================================================================
diff -u -r87a22cbaa87daab0d7cedabc67452cead83d8630 -r945dcc1391faefe5f4ddb4f505361501d008e293
--- firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 87a22cbaa87daab0d7cedabc67452cead83d8630)
+++ firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 945dcc1391faefe5f4ddb4f505361501d008e293)
@@ -64,6 +64,9 @@
 static BOOL tareLoadCellRequest;                                                        ///< Flag indicates if load cell tare has been requested by HD.
 
 // ********** private function prototypes **********
+
+static RESERVOIR_ID_T getActiveReservoir( void );
+static U32 getReservoirFillVolumeTargetMl( void );
 static U32 getReservoirDrainVolumeTargetMl( void );
 
 /*********************************************************************//**
@@ -282,25 +285,6 @@
 
     return result;
 }
-
-/*********************************************************************//**
- * @brief
- * The getActiveReservoir function gets the active reservoir.
- * @details Inputs: activeReservoir
- * @details Outputs: none
- * @return the currently active reservoir.
- *************************************************************************/
-RESERVOIR_ID_T getActiveReservoir( void )
-{
-    RESERVOIR_ID_T result = (RESERVOIR_ID_T)activeReservoir.data;
-
-    if ( OVERRIDE_KEY == activeReservoir.override )
-    {
-        result = (RESERVOIR_ID_T)activeReservoir.ovData;
-    }
-
-    return result;
-}
 
 /*********************************************************************//**
  * @brief
@@ -320,39 +304,24 @@
 
     return inactiveReservoir;
 }
-
-/*********************************************************************//**
- * @brief
- * The getReservoirFillVolumeTargetMl function gets the reservoir fill volume (in mL).
- * @details Inputs: fillVolumeTargetMl
- * @details Outputs: none
- * @return the current target reservoir fill volume (in mL).
- *************************************************************************/
-U32 getReservoirFillVolumeTargetMl( void )
-{
-    U32 result = fillVolumeTargetMl.data;
-
-    if ( OVERRIDE_KEY == fillVolumeTargetMl.override )
-    {
-        result = fillVolumeTargetMl.ovData;
-    }
-
-    return result;
-}
 
 /*********************************************************************//**
  * @brief
- * The resetReservoirLoadCellsOffset function sets the reservoir's load cells
- * offset to zero.
- * @details Inputs: associateLoadCell[], redundantLoadCell[]
- * @details Outputs: reset reservoir's associate load cells auto calibration offset
+ * The hasTargetFillVolumeReached function checks if the target fill volume
+ * for specific reservoir has been reached.
+ * @details Inputs: fillVolumeTargetMl
+ * @details Outputs: none
  * @param reservoirId reservoir id
- * @return none
+ * @return TRUE if target fill volume has been reached, FALSE if not.
  *************************************************************************/
-void resetReservoirLoadCellsOffset( RESERVOIR_ID_T reservoirId )
+BOOL hasTargetFillVolumeReached( RESERVOIR_ID_T reservoirId )
 {
-    resetLoadCellOffset( associateLoadCell[ reservoirId ] );
-    resetLoadCellOffset( redundantLoadCell[ reservoirId ] );
+    F32 const loadcellWeight = getLoadCellFilteredWeight( associateLoadCell[ reservoirId ] );
+    F32 const redundantLoadcellWeight = getLoadCellFilteredWeight( redundantLoadCell[ reservoirId ] );
+    U32 const targetFillVolume = getReservoirFillVolumeTargetMl();
+    BOOL const hasTargetReached = ( loadcellWeight >= targetFillVolume ) || ( redundantLoadcellWeight >= targetFillVolume );
+
+    return hasTargetReached;
 }
 
 /*********************************************************************//**
@@ -399,6 +368,59 @@
 
 /*********************************************************************//**
  * @brief
+ * The resetReservoirLoadCellsOffset function sets the reservoir's load cells
+ * offset to zero.
+ * @details Inputs: associateLoadCell[], redundantLoadCell[]
+ * @details Outputs: reset reservoir's associate load cells auto calibration offset
+ * @param reservoirId reservoir id
+ * @return none
+ *************************************************************************/
+void resetReservoirLoadCellsOffset( RESERVOIR_ID_T reservoirId )
+{
+    resetLoadCellOffset( associateLoadCell[ reservoirId ] );
+    resetLoadCellOffset( redundantLoadCell[ reservoirId ] );
+}
+
+/*********************************************************************//**
+ * @brief
+ * The getActiveReservoir function gets the active reservoir.
+ * @details Inputs: activeReservoir
+ * @details Outputs: none
+ * @return the currently active reservoir.
+ *************************************************************************/
+static RESERVOIR_ID_T getActiveReservoir( void )
+{
+    RESERVOIR_ID_T result = (RESERVOIR_ID_T)activeReservoir.data;
+
+    if ( OVERRIDE_KEY == activeReservoir.override )
+    {
+        result = (RESERVOIR_ID_T)activeReservoir.ovData;
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The getReservoirFillVolumeTargetMl function gets the reservoir fill volume (in mL).
+ * @details Inputs: fillVolumeTargetMl
+ * @details Outputs: none
+ * @return the current target reservoir fill volume (in mL).
+ *************************************************************************/
+static U32 getReservoirFillVolumeTargetMl( void )
+{
+    U32 result = fillVolumeTargetMl.data;
+
+    if ( OVERRIDE_KEY == fillVolumeTargetMl.override )
+    {
+        result = fillVolumeTargetMl.ovData;
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
  * The getReservoirDrainVolumeTargetMl function gets the reservoir drain volume (in mL).
  * @details Inputs: drainVolumeTargetMl
  * @details Outputs: none
Index: firmware/App/Services/Reservoirs.h
===================================================================
diff -u -r87a22cbaa87daab0d7cedabc67452cead83d8630 -r945dcc1391faefe5f4ddb4f505361501d008e293
--- firmware/App/Services/Reservoirs.h	(.../Reservoirs.h)	(revision 87a22cbaa87daab0d7cedabc67452cead83d8630)
+++ firmware/App/Services/Reservoirs.h	(.../Reservoirs.h)	(revision 945dcc1391faefe5f4ddb4f505361501d008e293)
@@ -60,12 +60,11 @@
 BOOL startTrimmerHeaterCmd( void );                    // handle start trimmer heater control command from HD
 BOOL stopTrimmerHeaterCmd( void );                     // handle stop trimmer heater control command from HD
 
-RESERVOIR_ID_T getActiveReservoir( void );
 RESERVOIR_ID_T getInactiveReservoir( void );
-U32 getReservoirFillVolumeTargetMl( void );
+BOOL hasTargetFillVolumeReached( RESERVOIR_ID_T reservoirId );
+BOOL hasTargetDrainVolumeReached( RESERVOIR_ID_T reservoirId , U32 timeout );
 
 void resetReservoirLoadCellsOffset( RESERVOIR_ID_T reservoirId );
-BOOL hasTargetDrainVolumeReached( RESERVOIR_ID_T reservoirId , U32 timeout );
 
 BOOL testSetDGActiveReservoirOverride( RESERVOIR_ID_T value );
 BOOL testResetDGActiveReservoirOverride( void );