Index: firmware/App/Modes/PreTreatmentRecirc.c
===================================================================
diff -u -r0a4dcd288d4347b85baaa0b07da568b6add5eac7 -r75e1ae332d1446dddf9b8d4ce6e8317449c57d67
--- firmware/App/Modes/PreTreatmentRecirc.c	(.../PreTreatmentRecirc.c)	(revision 0a4dcd288d4347b85baaa0b07da568b6add5eac7)
+++ firmware/App/Modes/PreTreatmentRecirc.c	(.../PreTreatmentRecirc.c)	(revision 75e1ae332d1446dddf9b8d4ce6e8317449c57d67)
@@ -7,8 +7,8 @@
 *
 * @file    PreTreatmentRecirc.c
 *
-* @author  (last)      Dara Navaei
-* @date    (last)      03-Nov-2022
+* @author  (last)      Michael Garthwaite
+* @date    (last)      19-Jan-2023
 *
 * @author  (original)  Quang Nguyen
 * @date    (original)  08-Feb-2021
@@ -22,6 +22,8 @@
 #include "DGInterface.h"
 #include "PreTreatmentRecirc.h"
 #include "Switches.h"
+#include "SystemCommMessages.h"
+#include "Timers.h"
 #include "Valves.h"
 
 /**
@@ -31,14 +33,19 @@
 
 // ********** private definitions **********
 
-#define BLOOD_PUMP_RECIRC_FLOW_RATE                         100                 ///< Blood pump flow rate during recirculation in mL/min.
-/// TODO: Restore to 100 when DPi flow control is fixed.
-#define DIALYSATE_PUMP_RECIRC_FLOW_RATE                     250                 ///< Dialysate pump flow rate during recirculation in mL/min.
+#define BLOOD_PUMP_RECIRC_FLOW_RATE                         100                             ///< Blood pump flow rate during recirculation in mL/min.
+// TODO: Restore to 100 when DPi flow control is fixed.
+#define DIALYSATE_PUMP_RECIRC_FLOW_RATE                     250                             ///< Dialysate pump flow rate during recirculation in mL/min.
+#define WARNING_MEDIUM_PRIME_COMPLETED_TIME_MS              ( 90 * 60 * MS_PER_SECOND )     ///< Pre-Treatment recirc time before medium priority warning in min.
+#define WARNING_HIGH_PRIME_COMPLETED_TIME_MS                ( 120 * 60 * MS_PER_SECOND )    ///< Pre-Treatment recirc time before high priority alarm in min.
 
 // ********** private data **********
 
-static HD_PRE_TREATMENT_RECIRC_STATE_T currentPreTreatmentRecircState;          ///< Current state of the pre-treatment recirculate state machine.
-static BOOL recircResumeRequested;                                              ///< Flag indicates alarm requesting to resume pre-treatment recirculate.
+static HD_PRE_TREATMENT_RECIRC_STATE_T currentPreTreatmentRecircState;                      ///< Current state of the pre-treatment recirculate state machine.
+static BOOL recircResumeRequested;                                                          ///< Flag indicates alarm requesting to resume pre-treatment recirculate.
+static U32  preTxRecircStartTime;                                                           ///< Time pre-treatment re-circulate state started.
+static BOOL recircTOWarningGiven;                                                           ///< Flag indicates 90 minute warning given.
+static BOOL recircTOAlarmGiven;                                                             ///< Flag indicates 2 hour alarm triggered.
 
 // ********** private function prototypes **********
 
@@ -58,6 +65,9 @@
 void initPreTreatmentRecirc( void )
 {
     currentPreTreatmentRecircState = PRE_TREATMENT_RECIRC_STATE;
+    preTxRecircStartTime = getMSTimerCount();
+    recircTOWarningGiven = FALSE;
+    recircTOAlarmGiven = FALSE;
 
     resetPreTreatmentRecircFlags();
 }
@@ -85,6 +95,16 @@
  *************************************************************************/
 void execPreTreatmentRecirc( void )
 {
+    HD_PRE_TREATMENT_RECIRC_STATE_T priorSubState = currentPreTreatmentRecircState;
+
+    // Alarm if 2 hours recirculating
+    if ( ( recircTOAlarmGiven != TRUE ) && ( TRUE == didTimeout( preTxRecircStartTime, WARNING_HIGH_PRIME_COMPLETED_TIME_MS ) ) )
+    {
+        recircTOAlarmGiven = TRUE;
+        clearAlarm( ALARM_ID_PRIME_COMPLETED_MEDIUM );
+        activateAlarmNoData( ALARM_ID_PRIME_COMPLETED_HIGH );
+    }
+
     // execute pre-treatment recirculate state machine
     switch ( currentPreTreatmentRecircState )
     {
@@ -101,6 +121,10 @@
             break;
     }
 
+    if ( priorSubState != currentPreTreatmentRecircState )
+    {
+        SEND_EVENT_WITH_2_U32_DATA( HD_EVENT_SUB_STATE_CHANGE, priorSubState, currentPreTreatmentRecircState );
+    }
     // All flags should be handled by now, reset in case flags not handle in current state
     resetPreTreatmentRecircFlags();
 }
@@ -187,6 +211,14 @@
 {
     HD_PRE_TREATMENT_RECIRC_STATE_T state = PRE_TREATMENT_RECIRC_STATE;
 
+    // Warn user if 90 minutes recirculating
+    if ( ( recircTOWarningGiven != TRUE ) && ( TRUE == didTimeout( preTxRecircStartTime, WARNING_MEDIUM_PRIME_COMPLETED_TIME_MS ) ) )
+    {
+        recircTOWarningGiven = TRUE;
+        clearAlarm( ALARM_ID_PRIME_COMPLETED_LOW_PRIORITY );
+        activateAlarmNoData( ALARM_ID_PRIME_COMPLETED_MEDIUM );
+    }
+
     if ( TRUE == doesAlarmStatusIndicateStop() )
     {
         signalDialOutPumpHardStop();