Index: firmware/App/Modes/StateTxBloodPrime.c
===================================================================
diff -u -rc7f561ca059b4fada1250823c6462bda68d39587 -r35eaef35568eefc648519dab7e1d8e289dca2f8b
--- firmware/App/Modes/StateTxBloodPrime.c	(.../StateTxBloodPrime.c)	(revision c7f561ca059b4fada1250823c6462bda68d39587)
+++ firmware/App/Modes/StateTxBloodPrime.c	(.../StateTxBloodPrime.c)	(revision 35eaef35568eefc648519dab7e1d8e289dca2f8b)
@@ -439,25 +439,42 @@
 *************************************************************************/
 BOOL bloodPrimeHandleBloodFlowChangeRequest( MESSAGE_T *message )
 {
-    BOOL result = FALSE;
+    BOOL result   = FALSE;
+    BOOL accepted = FALSE;
     REQUEST_REJECT_REASON_CODE_T rejReason = REQUEST_REJECT_REASON_INVALID_REQUEST_FORMAT;
-    UI_RESPONSE_PAYLOAD_T response;
 
     if ( sizeof(U32) == message->hdr.payloadLen )
     {
         U32 requestedRate;
-        memcpy( &requestedRate, message->payload, sizeof( U32 ) );
+        memcpy( &requestedRate, message->payload, sizeof(U32) );
         result = TRUE;
-        requestedBloodFlowRate_mL_min = requestedRate;
-        pendingFlowChangeRequest = TRUE;
-        rejReason = REQUEST_REJECT_REASON_NONE;
+
+        if ( ( BLOOD_PRIME_RAMP_STATE == bloodPrimeState ) || ( BLOOD_PRIME_RUN_STATE  == bloodPrimeState ) )
+        {
+            if ( ( requestedRate >= 50 ) && ( requestedRate <= 500 ) )
+            {
+                requestedBloodFlowRate_mL_min = requestedRate;
+                pendingFlowChangeRequest      = TRUE;
+                accepted  = TRUE;
+                rejReason = REQUEST_REJECT_REASON_NONE;
+            }
+            else
+            {
+                rejReason = REQUEST_REJECT_REASON_INVALID_COMMAND;
+            }
+        }
+        else
+        {
+            rejReason = REQUEST_REJECT_REASON_INVALID_COMMAND;
+        }
     }
+    {
+        UI_RESPONSE_PAYLOAD_T respPayload;
+        respPayload.accepted        = accepted;
+        respPayload.rejectionReason = rejReason;
+        sendMessage( MSG_ID_TD_TREATMENT_SET_POINT_BLOOD_FLOW_CHANGE_RESPONSE, COMM_BUFFER_OUT_CAN_TD_2_UI, (U08*)(&respPayload), sizeof(UI_RESPONSE_PAYLOAD_T) );
+    }
 
-    // Respond to request
-    response.accepted = result;
-    response.rejectionReason = rejReason;
-    sendMessage( MSG_ID_TD_TREATMENT_SET_POINT_BLOOD_FLOW_CHANGE_RESPONSE, COMM_BUFFER_OUT_CAN_TD_2_UI, (U08*)(&response), sizeof( UI_RESPONSE_PAYLOAD_T ) );
-
     return result;
 }