Index: firmware/App/Services/AlarmMgmt.c
===================================================================
diff -u -r75868c86d86060f8ec8fde969a479e186e51d9a0 -r821d1609f976b1fc01389f2e865aebcaa6434a78
--- firmware/App/Services/AlarmMgmt.c	(.../AlarmMgmt.c)	(revision 75868c86d86060f8ec8fde969a479e186e51d9a0)
+++ firmware/App/Services/AlarmMgmt.c	(.../AlarmMgmt.c)	(revision 821d1609f976b1fc01389f2e865aebcaa6434a78)
@@ -20,7 +20,8 @@
 #include "AlarmMgmt.h"
 #include "CPLD.h"
 #include "OperationModes.h"
-#include "PersistentAlarm.h"
+#include "PersistentAlarm.h"
+#include "Reservoirs.h"
 #include "SafetyShutdown.h"
 #include "SystemComm.h"
 #include "SystemCommMessages.h"
@@ -196,12 +197,21 @@
  *************************************************************************/
 void activateAlarm2Data( ALARM_ID_T alarm, ALARM_DATA_T alarmData1, ALARM_DATA_T alarmData2 )
 {
-    // broadcast alarm and data if alarm not already active
-    if ( ( FALSE == alarmIsActive[ alarm ] ) && ( TRUE == isHDCommunicating() ) )
-    {
-        broadcastAlarmTriggered( alarm, alarmData1, alarmData2 );
+    HD_MODE_SUB_MODE_T hdModes;
+
+    getHDOperationMode( &hdModes );
+
+    // prevent alarm trigger if property blocks in current mode/state
+    if ( ( ( ALARM_TABLE[ alarm ].alarmBlockRinseback != TRUE ) || ( hdModes.hdMode != MODE_TREA ) || ( hdModes.hdSubMode != TREATMENT_RINSEBACK_STATE ) ) &&
+         ( ( ALARM_TABLE[ alarm ].alarmBlockEndTx != TRUE ) || ( hdModes.hdMode != MODE_POST ) ) )
+    {
+        // broadcast alarm and data if alarm not already active
+        if ( ( FALSE == alarmIsActive[ alarm ] ) && ( TRUE == isHDCommunicating() ) )
+        {
+            broadcastAlarmTriggered( alarm, alarmData1, alarmData2 );
+        }
+        activateAlarm( alarm );
     }
-    activateAlarm( alarm );
 }
 
 /*********************************************************************//**
Index: firmware/App/Services/SystemComm.c
===================================================================
diff -u -rd325999b7b3ea03b7e294cb8a0b97df93812fbe9 -r821d1609f976b1fc01389f2e865aebcaa6434a78
--- firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision d325999b7b3ea03b7e294cb8a0b97df93812fbe9)
+++ firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision 821d1609f976b1fc01389f2e865aebcaa6434a78)
@@ -160,7 +160,7 @@
  *************************************************************************/
 BOOL isHDCommunicating( void )
 {
-    return getU32OverrideValue(&hdCommunicationStatus);
+    return getU32OverrideValue( &hdCommunicationStatus );
 }
 
 /*********************************************************************//**
@@ -668,6 +668,7 @@
     if ( TRUE == didTimeout( timeOfLastHDCheckIn, HD_COMM_TIMEOUT_IN_MS ) )
     {
         hdCommunicationStatus.data = FALSE;
+        setHDOperationMode( 0, 0 );   // If HD off or not connected, consider HD mode is fault.
     }
 }
 
Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r8912f5ad5d579105c721ce283c9deaa517eec7e1 -r821d1609f976b1fc01389f2e865aebcaa6434a78
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 8912f5ad5d579105c721ce283c9deaa517eec7e1)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 821d1609f976b1fc01389f2e865aebcaa6434a78)
@@ -4765,11 +4765,8 @@
  *************************************************************************/
 void handleTestDGDialinCheckIn( MESSAGE_T* message )
 {
-    BOOL status = FALSE;
-
     if ( 0 == message->hdr.payloadLen )
     {
-        status = TRUE;
         setDialinCheckInTimeStamp();
     }
 }