Index: firmware/App/Controllers/SubstitutionPump.c
===================================================================
diff -u -r83d4e437a4679b5d01b9b7a695484113a54c122b -r4a1f0518f867d1bc5d27d452a8306e43159e9a51
--- firmware/App/Controllers/SubstitutionPump.c	(.../SubstitutionPump.c)	(revision 83d4e437a4679b5d01b9b7a695484113a54c122b)
+++ firmware/App/Controllers/SubstitutionPump.c	(.../SubstitutionPump.c)	(revision 4a1f0518f867d1bc5d27d452a8306e43159e9a51)
@@ -56,7 +56,7 @@
 #define SUBSTITUTION_PUMP_CONTROL_NOT_RESET                  0x20                                               ///< Substitution pump control not reset.
 #define SUBSTITUTION_PUMP_CONTROL_SLEEP_OFF                  0x40                                               ///< Substitution pump control sleep off.
 
-#define SUBSTITUTION_PUMP_TRANS_TO_RAMP_SPEED_THRESHOLD_MLPM 10.0F                                              ///< Substitution pump transition to ramp to target speed threshold in mL/min.
+#define SUBSTITUTION_PUMP_TRANS_TO_RAMP_SPEED_THRESHOLD_MLPM 20.0F                                              ///< Substitution pump transition to ramp to target speed threshold in mL/min.
 #define SUBSTITUTION_PUMP_RAMP_SPEED_INCREMENT               5.0F                                               ///< Speed increase (mL/min) when controlling Substitution pump to target step speed.
 
 #define SUBSTITUTION_PUMP_CNT_TO_RPM(cnt)                    ( 60 / ( cnt * 0.0001 ) )                          ///< Conversion function for hall sensor cnt to rpm. rpm = 60/(cnt*100uS).
@@ -257,20 +257,22 @@
 static SUBSTITUTION_PUMP_STATE_T handleSubstitutionPumpControlTargetSpeedState( SUBSTITUTION_PUMPS_T pumpId )
 {
     SUBSTITUTION_PUMP_STATE_T state = SUBSTITUTION_PUMP_CONTROL_TARGET_SPEED_STATE;
-    F32 targetToCurreSpeedDiffMLPM = fabs( getSubstitutionPumpTargetRate( pumpId ) - substitutionPumps[ pumpId ].currentPumpSpeed );
+    F32 pumpTargetSpeed = getSubstitutionPumpTargetRate( pumpId ) * SUBSTITUTION_PUMP_VOLUME_PER_REV; // Translate from ml/min to RPM.
+    F32 currentToTargetDiff = fabs( pumpTargetSpeed - substitutionPumps[ pumpId ].currentPumpSpeed );
 
     if ( ++substitutionPumps[ pumpId ].controlTimerCounter >= SUBSTITUTION_PUMP_CONTROL_INTERVAL )
     {
         substitutionPumps[ pumpId ].controlTimerCounter = 0;
         stepSubstitutionPumpToTargetRate( pumpId );
     }
 
-    if ( targetToCurreSpeedDiffMLPM >= SUBSTITUTION_PUMP_TRANS_TO_RAMP_SPEED_THRESHOLD_MLPM )
+    if ( currentToTargetDiff >= SUBSTITUTION_PUMP_TRANS_TO_RAMP_SPEED_THRESHOLD_MLPM )
     {
         // If the requested target speed is greater than the threshold, transition back to ramp state regardless of the status of the
         // control interval
         stepSubstitutionPumpToTargetRate( pumpId );
-        state = SUBSTITUTION_PUMP_RAMP_TO_TARGET_SPEED_STATE;
+        //TODO: Transition to ramp state if feature requires ramping state.
+
     }
 
     //Stop the pump if requested.
Index: firmware/App/Services/Messaging.c
===================================================================
diff -u -r2c1a0857ad6987f387bdb8434c6498ab88cd1db8 -r4a1f0518f867d1bc5d27d452a8306e43159e9a51
--- firmware/App/Services/Messaging.c	(.../Messaging.c)	(revision 2c1a0857ad6987f387bdb8434c6498ab88cd1db8)
+++ firmware/App/Services/Messaging.c	(.../Messaging.c)	(revision 4a1f0518f867d1bc5d27d452a8306e43159e9a51)
@@ -293,7 +293,7 @@
     { MSG_ID_FP_SET_RECOVERY_VALVES_REQUEST,                                        &testIOFPSetValveRecoveryConfig },
     { MSG_ID_DD_SUBSTITUTION_PUMP_START_STOP_OVERRIDE_REQUEST,                      &testSubstitutionPumpStartStopOverride },
     { MSG_ID_DD_SUBSTITUTION_PUMP_BROADCAST_INTERVAL_OVERRIDE_REQUEST,              &testSubstitutionPumpDataPublishIntervalOverride },
-    { MSG_ID_DD_SUBSTITUTION_PUMP_TARGET_SPEED_OVERRIDE_REQUEST,                    &testSubstitutionPumpTargetRateOverride },
+    { MSG_ID_DD_SUBSTITUTION_PUMP_TARGET_RATE_OVERRIDE_REQUEST,                    &testSubstitutionPumpTargetRateOverride },
 };
 
 /// Calculation for number of entries in the incoming message function handler look-up table.