Index: firmware/App/Modes/ModeGenIdle.c
===================================================================
diff -u -r6952b2201dff87a6a20282c759c890580e3fd1db -rae27d75b0dad002d8ffb52c4b5bd595ece298ed3
--- firmware/App/Modes/ModeGenIdle.c	(.../ModeGenIdle.c)	(revision 6952b2201dff87a6a20282c759c890580e3fd1db)
+++ firmware/App/Modes/ModeGenIdle.c	(.../ModeGenIdle.c)	(revision ae27d75b0dad002d8ffb52c4b5bd595ece298ed3)
@@ -302,7 +302,8 @@
 static DG_GEN_IDLE_MODE_STATE_T handleFlushWaterState( void )
 {
     DG_GEN_IDLE_MODE_STATE_T result = DG_GEN_IDLE_MODE_STATE_FLUSH_WATER;
-    F32 reservoirWeight = getReservoirWeight( getInactiveReservoir() );
+    DG_RESERVOIR_ID_T currentInactiveReservoir = getInactiveReservoir();
+    F32 reservoirWeight = getReservoirWeight( currentInactiveReservoir );
 
     if ( ( TRUE == isAlarmActive( ALARM_ID_DG_ACID_BOTTLE_LOW_VOLUME ) ) || ( TRUE == isAlarmActive( ALARM_ID_DG_BICARB_BOTTLE_LOW_VOLUME ) ) )
     {
@@ -318,10 +319,10 @@
         startFillCmd( getTargetFillVolumeML(), getTargetFillFlowRateLPM() );
     }
 
-    if ( getInactiveReservoir() != inactiveReservoir )
+    if ( currentInactiveReservoir != inactiveReservoir )
     {
         // Inactive Reservoir changed, update the start value
-        inactiveReservoir = getInactiveReservoir();
+        inactiveReservoir = currentInactiveReservoir;
         initialReservoirWeight = getReservoirWeight( inactiveReservoir );
     }