Index: firmware/App/Controllers/AirTrap.c
===================================================================
diff -u -rab5e8c9e9ea574c12b2d7e245d79373f91d0829b -r493b74788dde91fc09303df6185bd9fa90de52d0
--- firmware/App/Controllers/AirTrap.c	(.../AirTrap.c)	(revision ab5e8c9e9ea574c12b2d7e245d79373f91d0829b)
+++ firmware/App/Controllers/AirTrap.c	(.../AirTrap.c)	(revision 493b74788dde91fc09303df6185bd9fa90de52d0)
@@ -72,10 +72,8 @@
 
 static U32  fillStartTime = 0;                                                              ///< Time stamp for start of air trap fill.
 
-static U32 airPumpUpperLevelCtr = 0;                                                        ///< Timer count for air pump persistence.
+static BOOL airTrapValveOpenAtStablePressureState = FALSE;                                  ///< Periodic AirTrap fill during pressure stable state, to clear any accumulated bubbles
 
-static BOOL airTrapValveOpenAtStablePressureState = FALSE;                                  ///< AirTrap valve open at every 15 minutes of pressure stable state, to clear any accumulated bubbles
-
 // ********** private function prototypes **********
 
 static AIR_TRAP_STATE_T handleAirTrapManualControlState( void );
@@ -96,7 +94,6 @@
 
     resetAirTrap();
     airTrapDataPublicationTimerCounter      = DATA_PUBLISH_COUNTER_START_COUNT;
-    airPumpUpperLevelCtr                    = 0;
     airTrapValveOpenAtStablePressureState   = TRUE;
 
     for ( i = 0; i < NUM_OF_AIR_TRAP_LEVEL_SENSORS; i++ )
@@ -159,12 +156,12 @@
 
 /*********************************************************************//**
  * @brief
- * The signalAirTrapValveOpen function sets the flag to open up air trap valve.
- * @details Inputs: airTrapValveOpenAtStablePressureState
+ * The signalAirTrapValveOpen function sets the flag to fill air trap.
+ * @details Inputs: none
  * @details Outputs: airTrapValveOpenAtStablePressureState
  * @return none
  *************************************************************************/
-void signalAirTrapValveOpen( void )
+void signalAirTrapPeriodicFill( void )
 {
     // Open air trap valve
     airTrapValveOpenAtStablePressureState = TRUE;
@@ -343,11 +340,10 @@
         if ( AIR_PUMP_STATE_ON == getAirPumpState() )
         {
             setAirPumpState( AIR_PUMP_STATE_OFF );
-            airPumpUpperLevelCtr = 0;
         }
     }
 
-    //Open valve every 15 mins once during pressure stable state
+    //Open valve when requested during pressure stable state
     else if ( TRUE == airTrapValveOpenAtStablePressureState )
     {
         airTrapValveOpenAtStablePressureState = FALSE;
@@ -368,7 +364,6 @@
         if ( AIR_PUMP_STATE_OFF == getAirPumpState() )
         {
             setAirPumpState( AIR_PUMP_STATE_ON );
-            airPumpUpperLevelCtr = 0;
             signalInitiatePressureStabilization( USE_SHORT_STABILIZATION_PERIOD );
         }
     }
@@ -378,12 +373,8 @@
     {
         if ( AIR_PUMP_STATE_ON == getAirPumpState() )
         {
-            airPumpUpperLevelCtr++;
-            // Turn air pump off once we detect air at upper level and exceed persistence
-            if ( airPumpUpperLevelCtr >= AIR_PUMP_UPPER_LEVEL_PERSISTENCE )
-            {
-                setAirPumpState( AIR_PUMP_STATE_OFF );
-            }
+            // Turn air pump off once we detect air at upper level
+             setAirPumpState( AIR_PUMP_STATE_OFF );
         }
     }