Index: firmware/App/Modes/ModeTreatmentParams.c
===================================================================
diff -u -rf760ffc4b10556e5186e9ceb90294262063440ca -r0f11f6c0773aebad3f3a647bdc294f8cca357799
--- firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision f760ffc4b10556e5186e9ceb90294262063440ca)
+++ firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision 0f11f6c0773aebad3f3a647bdc294f8cca357799)
@@ -570,6 +570,15 @@
         result = FALSE;
     }
 
+    // Check Heparin pre-stop vs. no Heparin delivery
+    if ( ( stagedParams[ TREATMENT_PARAM_HEPARIN_PRE_STOP_TIME ].uInt > 0 ) &&
+         ( stagedParams[ TREATMENT_PARAM_HEPARIN_DISPENSE_RATE ].sFlt < NEARLY_ZERO ) &&
+         ( stagedParams[ TREATMENT_PARAM_HEPARIN_BOLUS_VOLUME ].sFlt < NEARLY_ZERO ) )
+    {
+        reasons[ TREATMENT_PARAM_HEPARIN_PRE_STOP_TIME ] = REQUEST_REJECT_REASON_HEPARIN_PRESTOP_WITH_NO_DISPENSE;
+        result = FALSE;
+    }
+
     // Check arterial alarm limits dependency
     if ( arterialPresLimitDelta < MIN_PRESSURE_ALARM_LIMIT_DELTA_MMHG )
     {