Index: firmware/App/Controllers/AirTrap.c
===================================================================
diff -u -raf2674758d7b9dbe05e348b318845975b423509f -r975a29bff552a9e657364bd36b11c4d491cf7fae
--- firmware/App/Controllers/AirTrap.c	(.../AirTrap.c)	(revision af2674758d7b9dbe05e348b318845975b423509f)
+++ firmware/App/Controllers/AirTrap.c	(.../AirTrap.c)	(revision 975a29bff552a9e657364bd36b11c4d491cf7fae)
@@ -179,7 +179,8 @@
     airTrapLevels[ AIR_TRAP_LEVEL_SENSOR_UPPER ].data = (U32)( TRUE == upper ? AIR_TRAP_LEVEL_AIR : AIR_TRAP_LEVEL_FLUID );
 
     // check level readings are valid
-    if ( ( TRUE == lower ) && ( FALSE == upper ) )
+    if ( ( AIR_TRAP_LEVEL_AIR == getAirTrapLevel( AIR_TRAP_LEVEL_SENSOR_LOWER ) ) &&
+         ( AIR_TRAP_LEVEL_FLUID == getAirTrapLevel( AIR_TRAP_LEVEL_SENSOR_UPPER ) ) )
     {
         if ( ++airTrapIllegalLevelSensorsCtr >= AIR_TRAP_ILLEGAL_LEVELS_PERSISTENCE )
         {
@@ -188,7 +189,10 @@
     }
     else
     {
-        airTrapIllegalLevelSensorsCtr--;
+        if ( airTrapIllegalLevelSensorsCtr > 0 )
+        {
+            airTrapIllegalLevelSensorsCtr--;
+        }
     }
 }
 
@@ -203,6 +207,7 @@
 void execAirTrapMonitorPriming( void )
 {
     // TODO - implement when priming sub-mode of pre-treatment mode is implemented.
+    // activateAlarmNoData( ALARM_ID_AIR_TRAP_FILL_DURING_PRIME );
 }
 
 /*********************************************************************//**
@@ -216,18 +221,14 @@
 void execAirTrapMonitorTreatment( void )
 {
     // check air trap fill timeout during treatment
-    if ( airTrapControllerState > AIR_TRAP_MANUAL_CONTROL_STATE )
+    if ( AIR_TRAP_VALVE_OPEN_STATE == airTrapControllerState )
     {
-        if ( AIR_TRAP_LEVEL_AIR == getAirTrapLevel( AIR_TRAP_LEVEL_SENSOR_LOWER ) )
-        {
-            F32 bldFlowRate = (F32)getTreatmentParameterU32( TREATMENT_PARAM_BLOOD_FLOW );  // function will never return zero
-            F32 fillTimeoutMS = ( VENOUS_LINE_VOLUME_ML / bldFlowRate ) * (F32)SEC_PER_MIN * (F32)MS_PER_SECOND;
+        F32 bldFlowRate = (F32)getTreatmentParameterU32( TREATMENT_PARAM_BLOOD_FLOW );  // function will never return zero
+        F32 fillTimeoutMS = ( VENOUS_LINE_VOLUME_ML / bldFlowRate ) * (F32)SEC_PER_MIN * (F32)MS_PER_SECOND;
 
-            if ( TRUE == didTimeout( fillStartTime, fillTimeoutMS ) )
-            {
-                activateAlarmNoData( ALARM_ID_AIR_TRAP_ILLEGAL_LEVELS );
-                setValveAirTrap( STATE_CLOSED );
-            }
+        if ( TRUE == didTimeout( fillStartTime, fillTimeoutMS ) )
+        {
+            activateAlarmNoData( ALARM_ID_AIR_TRAP_FILL_DURING_TREATMENT );
         }
     }
 }
@@ -511,7 +512,7 @@
 {
     BOOL result = FALSE;
 
-    if ( sensor < NUM_OF_AIR_TRAP_LEVEL_SENSORS )
+    if ( ( sensor < NUM_OF_AIR_TRAP_LEVEL_SENSORS ) && ( level < NUM_OF_AIR_TRAP_LEVELS ) )
     {
         if ( TRUE == isTestingActivated() )
         {
Index: firmware/App/Controllers/DGInterface.h
===================================================================
diff -u -rde5a0d43bdef611d963d11855bc958a8d8899a09 -r975a29bff552a9e657364bd36b11c4d491cf7fae
--- firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision de5a0d43bdef611d963d11855bc958a8d8899a09)
+++ firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision 975a29bff552a9e657364bd36b11c4d491cf7fae)
@@ -32,8 +32,12 @@
 
 // ********** public definitions **********
 
-#define DRAIN_RESERVOIR_TO_VOLUME_ML        200                 ///< Drain reservoir to this volume (in mL) during treatment.
-#define FILL_RESERVOIR_TO_VOLUME_ML         1700                ///< Fill reservoir to this volume (in mL) during treatment.
+#define DRAIN_RESERVOIR_TO_VOLUME_ML        200                 ///< Drain reservoir to this volume (in mL) during treatment.
+#ifndef V1_5_SYSTEM
+#define FILL_RESERVOIR_TO_VOLUME_ML         1700                ///< Fill reservoir to this volume (in mL) during treatment.
+#else
+#define FILL_RESERVOIR_TO_VOLUME_ML         1300                ///< Fill reservoir to this volume (in mL) during treatment.
+#endif
 
 /// Enumeration of DG reservoirs.
 typedef enum DG_Reservoirs
Index: firmware/App/Controllers/Valves.h
===================================================================
diff -u -rb1c2d54d3d029ab1340d91193a7a4c81db8ba29d -r975a29bff552a9e657364bd36b11c4d491cf7fae
--- firmware/App/Controllers/Valves.h	(.../Valves.h)	(revision b1c2d54d3d029ab1340d91193a7a4c81db8ba29d)
+++ firmware/App/Controllers/Valves.h	(.../Valves.h)	(revision 975a29bff552a9e657364bd36b11c4d491cf7fae)
@@ -61,17 +61,7 @@
     U32  pwm;                          ///< Valve PWM
     U32  direction;                    ///< Valve direction
 } OVERRIDE_VALVES_PWM_DIR_SET_PAYLOAD_T;
-
-// TODO REMOVE the struct
-typedef struct
-{
-    S16 currentPos;
-    F32 current;
-    S16 cmdPosition;
-} HD_VALVE_FAST_DATA_T;
 #pragma pack(pop)
-HD_VALVE_FAST_DATA_T fastDataRemoveLater;
-// TODO REMOVE THE struct
 
 // ********** public function prototypes *********
 
Index: firmware/App/HDCommon.h
===================================================================
diff -u -raf2674758d7b9dbe05e348b318845975b423509f -r975a29bff552a9e657364bd36b11c4d491cf7fae
--- firmware/App/HDCommon.h	(.../HDCommon.h)	(revision af2674758d7b9dbe05e348b318845975b423509f)
+++ firmware/App/HDCommon.h	(.../HDCommon.h)	(revision 975a29bff552a9e657364bd36b11c4d491cf7fae)
@@ -56,6 +56,7 @@
 //    #define FLOW_DEBUG                      1           // test build sends flow, signal strength, and occlusion readings to debug UART
 //    #define EMC_TEST_BUILD                  1           // EMC test build - HD/DG run separately but connected, HD pumps toggle on/off w/ stop button
     #define ALARMS_DEBUG                    1           // triggered alarms sent to debug UART
+    #define V1_5_SYSTEM                     1           // build for v1.5 system
 
     #include <stdio.h>
     #include <strings.h>