Index: firmware/App/Modes/PreTreatmentRecirc.c
===================================================================
diff -u -r68f18c1952d37f75f27b7ca45969af2202729bb5 -rb20421d84b9049977c04f4752f4fc5697425f25c
--- firmware/App/Modes/PreTreatmentRecirc.c	(.../PreTreatmentRecirc.c)	(revision 68f18c1952d37f75f27b7ca45969af2202729bb5)
+++ firmware/App/Modes/PreTreatmentRecirc.c	(.../PreTreatmentRecirc.c)	(revision b20421d84b9049977c04f4752f4fc5697425f25c)
@@ -1,25 +1,27 @@
 /**************************************************************************
 *
-* Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
+* Copyright (c) 2021-2022 Diality Inc. - All Rights Reserved.
 *
 * THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
 * WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
 *
-* @file PreTreatmentRecirc.c
+* @file    PreTreatmentRecirc.c
 *
-* @author (last) Quang Nguyen
-* @date (last) 08-Feb-2021
+* @author  (last)      Sean Nash
+* @date    (last)      13-Jul-2022
 *
-* @author (original) Quang Nguyen
-* @date (original) 08-Feb-2021
+* @author  (original)  Quang Nguyen
+* @date    (original)  08-Feb-2021
 *
 ***************************************************************************/
 
+#include "AirTrap.h"
 #include "DialInFlow.h"
 #include "DialOutFlow.h"
 #include "BloodFlow.h"
 #include "DGInterface.h"
 #include "PreTreatmentRecirc.h"
+#include "Switches.h"
 #include "Valves.h"
 
 /**
@@ -29,8 +31,8 @@
 
 // ********** private definitions **********
 
-#define BLOOD_PUMP_RECIRC_FLOW_RATE                 100                 ///< Blood pump flow rate during recirculation in mL/min.
-#define DIALYSATE_PUMP_RECIRC_FLOW_RATE             100                 ///< 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.
+#define DIALYSATE_PUMP_RECIRC_FLOW_RATE                     100                 ///< Dialysate pump flow rate during recirculation in mL/min.
 
 // ********** private data **********
 
@@ -94,8 +96,7 @@
             break;
 
         default:
-            currentPreTreatmentRecircState = PRE_TREATMENT_RECIRC_STATE;
-            SET_ALARM_WITH_2_U32_DATA( ALARM_ID_HD_SOFTWARE_FAULT, SW_FAULT_ID_HD_INVALID_PRE_TREATMENT_RECIRC_STATE, (U32)currentPreTreatmentRecircState );
+            SET_ALARM_WITH_2_U32_DATA( ALARM_ID_HD_SOFTWARE_FAULT, SW_FAULT_ID_HD_INVALID_PRE_TREATMENT_RECIRC_STATE, currentPreTreatmentRecircState );
             break;
     }
 
@@ -152,13 +153,16 @@
  *************************************************************************/
 static void setupPreTreatmentRecirculate( void )
 {
+    doorClosedRequired( TRUE, TRUE );
+
     setValvePosition( VDI, VALVE_POSITION_C_CLOSE );
     setValvePosition( VDO, VALVE_POSITION_C_CLOSE );
     setValvePosition( VBA, VALVE_POSITION_B_OPEN );
     setValvePosition( VBV, VALVE_POSITION_B_OPEN );
     setValveAirTrap( STATE_CLOSED );
     cmdSetDGActiveReservoir( DG_RESERVOIR_1 );
     cmdStartDGTrimmerHeater();
+    startAirTrapControl();
 
     setBloodPumpTargetFlowRate( BLOOD_PUMP_RECIRC_FLOW_RATE, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
     setDialInPumpTargetFlowRate( DIALYSATE_PUMP_RECIRC_FLOW_RATE, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
@@ -183,6 +187,7 @@
         signalDialInPumpHardStop();
         signalBloodPumpHardStop();
         cmdStopDGTrimmerHeater();
+        endAirTrapControl();
 
         state = PRE_TREATMENT_RECIRC_STOPPED_STATE;
     }