Index: firmware/App/Controllers/PresOccl.c
===================================================================
diff -u -rceebe701c56e6ac41e93d399fdd9d2beebbf711c -r4b252f2f8a997498e959af9b5496d1fabd4bad2b
--- firmware/App/Controllers/PresOccl.c	(.../PresOccl.c)	(revision ceebe701c56e6ac41e93d399fdd9d2beebbf711c)
+++ firmware/App/Controllers/PresOccl.c	(.../PresOccl.c)	(revision 4b252f2f8a997498e959af9b5496d1fabd4bad2b)
@@ -905,6 +905,7 @@
         HD_OP_MODE_T hdMode = getCurrentOperationMode();
         U32 hdSubMode = getCurrentSubMode();
         BOOL ptxMode = ( MODE_PRET == hdMode && hdSubMode > HD_PRE_TREATMENT_CART_INSTALL_STATE ? TRUE : FALSE );
+        BOOL txModeRecirc = ( ( MODE_TREA == hdMode ) && ( TREATMENT_RECIRC_STATE == getTreatmentState() ) ? TRUE : FALSE );
 
         // Range check occlusion sensor (OB)
         if ( TRUE == isPersistentAlarmTriggered( ALARM_ID_HD_BP_OCCLUSION_OUT_OF_RANGE, outOfRange ) )
@@ -914,7 +915,7 @@
 
         // Check for occlusion in PreTreatment modes when the cartridge is installed
         // and setOcclusionInstallLevel has been called.
-        if ( MODE_PRET == getCurrentOperationMode() )
+        if ( MODE_PRET == hdMode )
         {
             if ( ( TRUE == isBloodPumpRunning() ) && ( getPreTreatmentSubState() > HD_PRE_TREATMENT_CART_INSTALL_STATE )
                     && ( getDrySelfTestsState() > DRY_SELF_TESTS_START_STATE ) )
@@ -928,7 +929,7 @@
             }
         }
         // Check for occlusion in Treatment modes where pumps are moving
-        else if ( MODE_TREA == getCurrentOperationMode() )
+        else if ( MODE_TREA == hdMode )
         {
             if ( TRUE == isBloodPumpRunning() )
             {
@@ -953,8 +954,9 @@
 #endif
         {   // only trigger alarm if BP is running
             if ( isBloodPumpRunning() != FALSE )
-            {   // must be in pre-treatment mode to trigger this alarm
-                if ( ( TRUE == ptxMode ) && ( venPres > VENOUS_PRESSURE_LIMIT_MAX_MMHG + VENOUS_PRESSURE_OCCL_OFFSET_MMHG ) )
+            {   // must be in pre-treatment OR treatment recirculation mode to trigger this alarm
+                if ( ( ( TRUE == ptxMode ) || ( TRUE == txModeRecirc ) )
+                        && ( venPres > VENOUS_PRESSURE_LIMIT_MAX_MMHG + VENOUS_PRESSURE_OCCL_OFFSET_MMHG ) )
                 {
                     if ( TRUE == isPersistentAlarmTriggered( ALARM_ID_HD_VENOUS_LINE_OCCLUSION, TRUE ) )
                     {