Index: firmware/App/Services/SystemComm.c
===================================================================
diff -u -rbb36d57ea11a646b277c8bbb22691be2e535da22 -rcbef3eeccf761b959283d027da24ac389df48434
--- firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision bb36d57ea11a646b277c8bbb22691be2e535da22)
+++ firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision cbef3eeccf761b959283d027da24ac389df48434)
@@ -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.
     }
 }
 
@@ -1028,7 +1029,7 @@
                 handleTestValveStateOverrideRequest( message );
                 break;
 
-            case MSG_ID_VALVES_STATES_PUBLISH_INTERVAL_OVERRIDE:
+            case MSG_ID_DG_VALVES_STATES_PUBLISH_INTERVAL_OVERRIDE:
                 handleTestValvesStatesPublishIntervalOverrideRequest( message );
                 break;
 
@@ -1185,11 +1186,11 @@
                 break;
 
             case MSG_ID_FILTER_FLUSH_TIME_PERIOD_OVERRIDE:
-                handleFilterFlushTimePeriodOverride( message );
+                handleFilterFlushTimePeriodOverride(message);
                 break;
 
-            case MSG_ID_DG_FANS_RPM_OVERRIDE:
-                handleFansRPMOverride( message );
+            case MSG_ID_DG_BLOCK_MESSAGE_TRANSMISSION:
+                handleTestBlockMessagesRequest( message );
                 break;
 
             case MSG_ID_DG_STOP_RTC_CLOCK:
@@ -1200,10 +1201,6 @@
                 handleSetDrainPumpMeasuredRPMOverrideRequest( message );
                 break;
 
-            case MSG_ID_DG_BLOCK_MESSAGE_TRANSMISSION:
-                handleTestBlockMessagesRequest( message );
-                break;
-
             case MSG_ID_DG_SUPER_CLEAR_ALARMS_CMD:
                 handleTestSuperClearAlarmsRequest( message );
                 break;
@@ -1216,6 +1213,10 @@
                 handleTestFansRPMAlarmStartTimeOffsetRequest( message );
                 break;
 
+            case MSG_ID_DG_FANS_RPM_OVERRIDE:
+                handleFansRPMOverride( message );
+                break;
+
             case MSG_ID_DG_USED_ACID_VOLUME_ML_OVERRIDE:
                 handleTestUsedAcidVolumeMLOverrideRequest( message );
                 break;
@@ -1262,14 +1263,14 @@
                 handleTestTareReservoirRequest( message );
                 break;
 
-            case MSG_ID_DG_DRAIN_PUMP_CURRENT_OVERRIDE:
-                handleTestDrainPumpMeasuredCurrentOverride( message );
-                break;
-
             case MSG_ID_DG_GEN_IDLE_PUBLISH_INTERVAL_OVERRIDE:
                 handleTestGenIdlePublishIntervalOverride( message );
                 break;
 
+            case MSG_ID_DG_DRAIN_PUMP_CURRENT_OVERRIDE:
+                handleSetDrainPumpMeasuredRPMOverrideRequest( message );
+                break;
+
             case MSG_ID_DG_DRAIN_PUMP_DIRECTION_OVERRIDE:
                 handleTestDGDrainPumpDirectionOverrideRequest( message );
                 break;
Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -rbb36d57ea11a646b277c8bbb22691be2e535da22 -rcbef3eeccf761b959283d027da24ac389df48434
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision bb36d57ea11a646b277c8bbb22691be2e535da22)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision cbef3eeccf761b959283d027da24ac389df48434)
@@ -422,7 +422,6 @@
     return result;
 }
 
-
 // ***********************************************************************
 // **************** Message Handling Helper Functions ********************
 // ***********************************************************************
@@ -3614,37 +3613,6 @@
 }
 
 /*********************************************************************//**
- * @brief
- * The handleFansRPMOverride function handles a request to override a fans RPM value.
- * @details Inputs: none
- * @details Outputs: message handled
- * @param message a pointer to the message to handle
- * @return none
- *************************************************************************/
-void handleFansRPMOverride( MESSAGE_T *message )
-{
-    TEST_OVERRIDE_ARRAY_PAYLOAD_T payload;
-    BOOL result = FALSE;
-
-    // verify payload length
-    if ( sizeof(TEST_OVERRIDE_ARRAY_PAYLOAD_T) == message->hdr.payloadLen )
-    {
-        memcpy( &payload, message->payload, sizeof(TEST_OVERRIDE_ARRAY_PAYLOAD_T) );
-        if ( FALSE == payload.reset )
-        {
-            result = testSetFanRPMOverride( payload.index, payload.state.f32 );
-        }
-        else
-        {
-            result = testResetFanRPMOverride( payload.index );
-        }
-    }
-
-    // respond to request
-    sendTestAckResponseMsg( (MSG_ID_T)message->hdr.msgID, result );
-}
-
-/*********************************************************************//**
 * @brief
 * The handleStopDGRTCClock function handles a request to stop the RTC clock.
 * @details Inputs: none
@@ -3783,10 +3751,41 @@
 
 /*********************************************************************//**
  * @brief
- * The handleTestFansRPMAlarmStartTimeOffsetRequest function handles a
- * request to set the fans RPM alarm start time offset.
+ * The handleFansRPMOverride function handles a request to override a fans RPM value.
  * @details Inputs: none
  * @details Outputs: message handled
+ * @param message a pointer to the message to handle
+ * @return none
+ *************************************************************************/
+void handleFansRPMOverride( MESSAGE_T *message )
+{
+    TEST_OVERRIDE_ARRAY_PAYLOAD_T payload;
+    BOOL result = FALSE;
+
+    // verify payload length
+    if ( sizeof(TEST_OVERRIDE_ARRAY_PAYLOAD_T) == message->hdr.payloadLen )
+    {
+        memcpy( &payload, message->payload, sizeof(TEST_OVERRIDE_ARRAY_PAYLOAD_T) );
+        if ( FALSE == payload.reset )
+        {
+            result = testSetFanRPMOverride( payload.index, payload.state.f32 );
+        }
+        else
+        {
+            result = testResetFanRPMOverride( payload.index );
+        }
+    }
+
+    // respond to request
+    sendTestAckResponseMsg( (MSG_ID_T)message->hdr.msgID, result );
+}
+
+/*********************************************************************//**
+ * @brief
+ * The handleTestFansRPMAlarmStartTimeOverrideRequest function handles a
+ * request to override the fan RPM alarm start time.
+ * @details Inputs: none
+ * @details Outputs: message handled
  * @param message : a pointer to the message to handle
  * @return none
  *************************************************************************/
@@ -3809,7 +3808,6 @@
 }
 
 /*********************************************************************//**
- * @brief
  * The handleTestUsedAcidVolumeMLOverrideRequest function handles a
  * request to override the acid volume.
  * @details Inputs: none
Index: firmware/App/Services/SystemCommMessages.h
===================================================================
diff -u -rbb36d57ea11a646b277c8bbb22691be2e535da22 -rcbef3eeccf761b959283d027da24ac389df48434
--- firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision bb36d57ea11a646b277c8bbb22691be2e535da22)
+++ firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision cbef3eeccf761b959283d027da24ac389df48434)
@@ -167,6 +167,12 @@
 // MSG_ID_DG_RESPONSE_SERVICE_MODE_REQUEST
 BOOL sendServiceModeResponse( BOOL accepted, U32 rejCode );
 
+// MSG_ID_HD_OP_MODE
+BOOL handleSetHDOperationMode( MESSAGE_T *message );
+
+// MSG_ID_HD_REQUEST_DG_USAGE_INFO
+void handleHDRequestDGUsageInfo( MESSAGE_T * message );
+
 // MSG_ID_DG_SET_SERVICE_TIME
 void handleSetDGServiceTime( MESSAGE_T *message );
 
@@ -396,6 +402,12 @@
 // MSG_ID_DG_DRAIN_PUMP_MEASURED_RPM_OVERRIDE
 void handleSetDrainPumpMeasuredRPMOverrideRequest( MESSAGE_T *message );
 
+// MSG_ID_DG_ALARM_INFO_SEND_INTERVAL_OVERRIDE
+void handleTestAlarmInfoSendIntervalOverrideRequest( MESSAGE_T *message );
+
+// MSG_ID_DG_SUPER_CLEAR_ALARMS_CMD
+void handleTestSuperClearAlarmsRequest( MESSAGE_T *message );
+
 // MSG_ID_DG_SET_FANS_RPM_ALARM_START_TIME_OFFSET
 void handleTestFansRPMAlarmStartTimeOffsetRequest( MESSAGE_T *message );
 
@@ -416,21 +428,27 @@
 void handleSetDGSoftwareConfigRecord( MESSAGE_T *message );
 #endif
 
+// MSG_ID_HD_REQUEST_DG_ALARMS
+void handleResendAllAlarmsCommand( MESSAGE_T *message );
+
 // MSG_ID_DG_HD_COMMUNICATION_STATUS
 void handleTestHDCommunicationStatusOverrideRequest( MESSAGE_T *message );
 
 // MSG_ID_DG_SET_PRIMARY_AND_TRIMMER_HEATERS_TARGET_TEMP
 void handleSetPrimaryAndTrimmerHeatersTargetTemperature( MESSAGE_T *message );
 
+// MSG_ID_DG_USED_ACID_VOLUME_ML_OVERRIDE
+void handleTestUsedAcidVolumeMLOverrideRequest(MESSAGE_T *message);
+
+// MSG_ID_DG_USED_BICARB_VOLUME_ML_OVERRIDE
+void handleTestUsedBicarbVolumeMLOverrideRequest(MESSAGE_T *message);
+
 // MSG_ID_DG_GET_USAGE_INFO_RECORD
 void handleGetDGUsageInfoRecord( MESSAGE_T *message );
 
 // MSG_ID_DG_SET_USAGE_INFO_RECORD
 void handleSetDGUsageInfoRecord( MESSAGE_T *message );
 
-// MSG_ID_HD_REQUEST_DG_ALARMS
-void handleResendAllAlarmsCommand( MESSAGE_T *message );
-
 // MSG_ID_DG_SET_OP_MODE_REQUEST
 void handleTestSetOpModeRequest( MESSAGE_T *message );