Index: firmware/App/Controllers/Valves.c
===================================================================
diff -u -rcff72ec53660ec3ff6775c0508e3c721240ffba2 -r6f2991204047ccbceeb5461f7c35af6d8f5dfd0b
--- firmware/App/Controllers/Valves.c	(.../Valves.c)	(revision cff72ec53660ec3ff6775c0508e3c721240ffba2)
+++ firmware/App/Controllers/Valves.c	(.../Valves.c)	(revision 6f2991204047ccbceeb5461f7c35af6d8f5dfd0b)
@@ -18,7 +18,8 @@
 #include "FPGA.h"
 #include "MessageSupport.h"
 #include "SystemCommMessages.h"
-#include "TaskPriority.h"
+#include "TaskPriority.h"
+#include "Timers.h"
 #include "Valves.h"
 
 /**
@@ -28,14 +29,25 @@
 
 // ********** private definitions **********
 
-#define DEENERGIZED                                 0                                                               ///< 0 for de-energized valve.
-#define ENERGIZED                                   1                                                               ///< 1 for energized valve.
-#define ALL_VALVES_DEENERGIZED                      0x0000                                                          ///< 0 in U16 bit field for all valves.
+#define DEENERGIZED                                     0                                                           ///< 0 for de-energized valve.
+#define ENERGIZED                                       1                                                           ///< 1 for energized valve.
+#define ALL_VALVES_DEENERGIZED                          0x0000                                                      ///< 0 in U16 bit field for all valves.
 
-#define MAX_VALVE_STATE_MISMATCH_COUNT              3                                                               ///< Maximum number of times commanded valves state can fail to match read back valve states in a row.
+#define MAX_VALVE_STATE_MISMATCH_COUNT                  3                                                           ///< Maximum number of times commanded valves state can fail to match read back valve states in a row.
 
-#define VALVES_STATE_PUB_INTERVAL                   ( MS_PER_SECOND / TASK_PRIORITY_INTERVAL )                      ///< Interval ( ms / task time) at which valves states are published on CAN bus.
-#define DATA_PUBLISH_COUNTER_START_COUNT            50                                                              ///< Data publish counter start count.
+#define VALVES_STATE_PUB_INTERVAL                       ( MS_PER_SECOND / TASK_PRIORITY_INTERVAL )                  ///< Interval ( ms / task time) at which valves states are published on CAN bus.
+#define DATA_PUBLISH_COUNTER_START_COUNT                50                                                          ///< Data publish counter start count.
+
+#define VPI_MIN_OPEN_TO_SKIP_DISINFECT_FLUSH_MS         ( 2 * SEC_PER_MIN *  MS_PER_SECOND )                        ///< VPi minimum required time to be open to skip disinfects flush state in milliseconds.
+#define VPI_MAX_OPEN_WINDOW_TO_SKIP_DISINFECT_FLUSH_MS  ( 30 * SEC_PER_MIN *  MS_PER_SECOND )                       ///< VPi maximum allowed time window that VPi could have been open in milliseconds.
+
+/// VPi open/close time status for disinfects
+typedef struct
+{
+    U32 vpiOpenStartTimeMS;                                                                                         ///< VPi open start time in milliseconds.
+    U32 vpiOpenDurationMS;                                                                                          ///< VPi duration that is has been open in milliseconds.
+    U32 vpiClosedStartTimeMS;                                                                                       ///< VPi closed start time in milliseconds.
+} VPI_OPEN_CLOSE_TIME_T;
 
 // ********** private data **********
 
@@ -48,6 +60,7 @@
 static OVERRIDE_U32_T valveStates[ NUM_OF_VALVES ];                                                                 ///< Currently commanded valves states.
 static OVERRIDE_U32_T valveSensedStates[ NUM_OF_VALVES ];                                                           ///< Valve sensed states override.
 static OVERRIDE_U32_T valvesStatesPublishInterval = { VALVES_STATE_PUB_INTERVAL, VALVES_STATE_PUB_INTERVAL, 0, 0 }; ///< Interval (in ms/task interval) at which to publish valves state to CAN bus.
+static VPI_OPEN_CLOSE_TIME_T vpiTime;                                                                               ///< VPi open/close time structure.
 
 // ********** private function prototypes **********
 
@@ -56,6 +69,7 @@
 static U16 fromU32ArrayToU16( void );
 static void publishValvesStates( void );
 static U32 getValveState( U32 valveID );
+static void checkVPiTimeStatus( void );
 
 /*********************************************************************//**
  * @brief
@@ -66,6 +80,7 @@
  * commandedValvesStates
  * @return none
  *************************************************************************/
+
 void initValves( void )
 {
     U32 i;
@@ -85,6 +100,8 @@
         valveSensedStates[ i ].override        = OVERRIDE_RESET;
     }
 
+    memset( &vpiTime, 0, sizeof( VPI_OPEN_CLOSE_TIME_T ) );
+
     valveStateMismatchCounter = 0;
     commandedValvesStates     = fromU32ArrayToU16();
     setFPGAValveStates( commandedValvesStates ); // initially set all valves to de-energized state via FPGA
@@ -136,6 +153,8 @@
     commandedValvesStates = fromU32ArrayToU16();
     setFPGAValveStates( commandedValvesStates );
 
+    checkVPiTimeStatus();
+
     // Publish valve states on interval
     publishValvesStates();
 }
@@ -403,8 +422,8 @@
 /*********************************************************************//**
  * @brief
  * The getValveStateName function gets the current valve state enum for given valve.
- * @details Inputs: valveStates[], valveSensedStates
- * @details Outputs: valveSensedStates
+ * @details Inputs: valveStates[]
+ * @details Outputs: none
  * @param valveID ID of valve to get state for
  * @return the current valve state for given valve in enum
  *************************************************************************/
@@ -462,6 +481,26 @@
     }
 
     return name;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The isFliterFlushRequired function checks whether filter flush is required in
+ * cleaning modes.
+ * @details Inputs: vpiTime
+ * @details Outputs: none
+ * @return TRUE if filter flush is required otherwise, FALSE
+ *************************************************************************/
+BOOL isFliterFlushRequired( void )
+{
+    BOOL status = TRUE;
+
+    if ( vpiTime.vpiOpenDurationMS >= VPI_MIN_OPEN_TO_SKIP_DISINFECT_FLUSH_MS )
+    {
+        status = ( calcTimeSince( vpiTime.vpiClosedStartTimeMS ) <= VPI_MAX_OPEN_WINDOW_TO_SKIP_DISINFECT_FLUSH_MS ? FALSE : TRUE );
+    }
+
+    return status;
 }
 
 /*********************************************************************//**
@@ -516,6 +555,29 @@
     return valveState;
 }
 
+/*********************************************************************//**
+ * @brief
+ * The checkVPiTimeStatus function checks the status of the VPi to see if
+ * it was open or closed.
+ * @details Inputs: vpiTime
+ * @details Outputs: vpiTime
+ * @return none
+ *************************************************************************/
+static void checkVPiTimeStatus( void )
+{
+    if ( ( VALVE_STATE_OPEN == getValveStateName( VPI ) ) && ( 0 == vpiTime.vpiOpenStartTimeMS ) )
+    {
+        vpiTime.vpiOpenStartTimeMS   = getMSTimerCount();
+        vpiTime.vpiClosedStartTimeMS = 0;
+    }
+    else if ( ( VALVE_STATE_CLOSED == getValveStateName( VPI ) ) && ( 0 == vpiTime.vpiClosedStartTimeMS ) )
+    {
+        vpiTime.vpiOpenDurationMS    = calcTimeSince( vpiTime.vpiOpenStartTimeMS );
+        vpiTime.vpiOpenStartTimeMS   = 0;
+        vpiTime.vpiClosedStartTimeMS = getMSTimerCount();
+    }
+}
+
 
 /*************************************************************************
  *                       TEST SUPPORT FUNCTIONS