Index: firmware/App/Modes/ModeInitPOST.c
===================================================================
diff -u -r0ca939ac0e3ad7d432152a89135075bfd67246df -rfdbb919248858aeffe5d23c2b6c57181e821f929
--- firmware/App/Modes/ModeInitPOST.c	(.../ModeInitPOST.c)	(revision 0ca939ac0e3ad7d432152a89135075bfd67246df)
+++ firmware/App/Modes/ModeInitPOST.c	(.../ModeInitPOST.c)	(revision fdbb919248858aeffe5d23c2b6c57181e821f929)
@@ -42,7 +42,6 @@
 #include "SystemCommMessages.h"
 #include "TaskGeneral.h"
 #include "Temperatures.h"
-#include "Timers.h"
 #include "Valves.h"
 #include "WatchdogMgmt.h"
 
@@ -80,7 +79,7 @@
 static UI_VERSIONS_T uiVersion = { 0, 0, 0, 0, 0 };             ///< Version and compatibility information reported by UI.
 static DG_VERSIONS_T dgVersion = { 0, 0, 0, 0, 0, 0, 0, 0, 0 }; ///< Version and compatibility information reported by DG.
 static U32 startPOSTDelayCounter = 0;                           ///< Start POST delay counter.
-static U32 SNAndInstConfigSendStartTimeMS;                      ///< serial number and institutional configuration send start time milliseconds.
+static BOOL hasSNAndInstBeenSent;                               ///< Boolean flag to check whether serial number and institutional record been sent.
 
 extern U32 savedResetReasonCode;                                ///< Saved reset reason code from sys_startup.c.
 
@@ -102,18 +101,18 @@
  *************************************************************************/
 void initInitAndPOSTMode( void )
 {
-    postState                      = POST_STATE_START;
-    postCompleted                  = FALSE;
-    postPassed                     = FALSE;
-    tempPOSTPassed                 = TRUE;
-    uiPOSTPassed                   = FALSE;
-    dgPOSTPassed                   = FALSE;
-    uiPOSTResultReceived           = FALSE;
-    dgPOSTResultReceived           = FALSE;
-    waitForUIPostTimerCtr          = 0;
-    postCompleteDelayTimerCtr      = 0;
-    startPOSTDelayCounter          = 0;
-    SNAndInstConfigSendStartTimeMS = getMSTimerCount();
+    postState                 = POST_STATE_START;
+    postCompleted             = FALSE;
+    postPassed                = FALSE;
+    tempPOSTPassed            = TRUE;
+    uiPOSTPassed              = FALSE;
+    dgPOSTPassed              = FALSE;
+    uiPOSTResultReceived      = FALSE;
+    dgPOSTResultReceived      = FALSE;
+    waitForUIPostTimerCtr     = 0;
+    postCompleteDelayTimerCtr = 0;
+    startPOSTDelayCounter     = 0;
+    hasSNAndInstBeenSent      = FALSE;
 }
 
 /*********************************************************************//**
@@ -628,7 +627,7 @@
  *************************************************************************/
 static void sendSerialNumberAndInstitutionalToUI( void )
 {
-    if ( ( TRUE == didTimeout( SNAndInstConfigSendStartTimeMS, SN_INST_SEND_TO_UI_TIME_INTERVAL_MS ) ) && ( postState > POST_STATE_NVDATAMGMT ) )
+    if ( ( FALSE == hasSNAndInstBeenSent ) && ( postState > POST_STATE_NVDATAMGMT ) )
     {
         MESSAGE_T message;
 
@@ -639,7 +638,7 @@
         handleHDSerialNumberRequest();
         handleSendInstitutionalRecordToUI( &message );
 
-        SNAndInstConfigSendStartTimeMS = getMSTimerCount();
+        hasSNAndInstBeenSent = TRUE;
     }
 }
 
Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r0ca939ac0e3ad7d432152a89135075bfd67246df -rfdbb919248858aeffe5d23c2b6c57181e821f929
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 0ca939ac0e3ad7d432152a89135075bfd67246df)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision fdbb919248858aeffe5d23c2b6c57181e821f929)
@@ -94,6 +94,11 @@
     U32 enableChemicalDisinfect;                            ///< Enable/disable chemical disinfect.
 } HD_INSTITUTIONAL_LOCAL_RECORD_T;
 
+typedef struct
+{
+    U08 topLevelSN[ MAX_TOP_LEVEL_SN_CHARS ];
+} LOCAL_TOP_SN_T;
+
 // ********** private data **********
 
 #ifndef CARTRIDGE_TEST_BUILD
@@ -3335,10 +3340,6 @@
  *************************************************************************/
 void handleHDSerialNumberRequest( void )
 {
-    typedef struct
-    {
-        U08 topLevelSN[ MAX_TOP_LEVEL_SN_CHARS ];
-    } LOCAL_TOP_SN_T;
     MESSAGE_T msg;
     HD_SYSTEM_RECORD_T system;
     U08 i;
@@ -3354,28 +3355,23 @@
     blankMessage( &msg );
     msg.hdr.msgID = MSG_ID_HD_SERIAL_NUMBER_RESPONSE;
 
-    // Check if the first element of the serial number is not 0 meaning that we are not sending empty serial number
-    // to the UI
-    if ( system.topLevelSN[0] != 0 )
+    // Add 1 byte for null terminator
+    msg.hdr.payloadLen = MAX_TOP_LEVEL_SN_CHARS + 1;
+
+    for ( i = 0; i < MAX_TOP_LEVEL_SN_CHARS; i++ )
     {
-        // Add 1 byte for null terminator
-        msg.hdr.payloadLen = MAX_TOP_LEVEL_SN_CHARS + 1;
+        // NOTE: A local variable was created to avoid system.topLevelSN in the messages list
+        // NOTE: For loop was used instead of memory copy to ensure it is not parsed in the messages list script
+        localTopLevelSN.topLevelSN[ i ] = system.topLevelSN[ i ];
+    }
 
-        for ( i = 0; i < MAX_TOP_LEVEL_SN_CHARS; i++ )
-        {
-            // NOTE: A local variable was created to avoid system.topLevelSN in the messages list
-            // NOTE: For loop was used instead of memory copy to ensure it is not parsed in the messages list script
-            localTopLevelSN.topLevelSN[ i ] = system.topLevelSN[ i ];
-        }
+    // Fill message payload
+    memcpy( payloadPtr, &localTopLevelSN, sizeof( LOCAL_TOP_SN_T ) );
+    payloadPtr += MAX_TOP_LEVEL_SN_CHARS;
+    *payloadPtr = 0;
 
-        // Fill message payload
-        memcpy( payloadPtr, &localTopLevelSN, sizeof( LOCAL_TOP_SN_T ) );
-        payloadPtr += MAX_TOP_LEVEL_SN_CHARS;
-        *payloadPtr = 0;
-
-        // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
-        serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
-    }
+    // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
 }
 
 /*********************************************************************//**
@@ -3713,7 +3709,7 @@
     memcpy( payloadPtr, instit, sizeof( HD_INSTITUTIONAL_LOCAL_RECORD_T ) );
 
     // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
-    serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_NOT_REQUIRED );
+    serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
 }
 
 /*********************************************************************//**