Index: firmware/App/Controllers/DGInterface.c
===================================================================
diff -u -r6419179374edcd65da462de84e8aeaefb7e20320 -raef738aab88159be8664b91d72b1682a0d0db541
--- firmware/App/Controllers/DGInterface.c	(.../DGInterface.c)	(revision 6419179374edcd65da462de84e8aeaefb7e20320)
+++ firmware/App/Controllers/DGInterface.c	(.../DGInterface.c)	(revision aef738aab88159be8664b91d72b1682a0d0db541)
@@ -17,12 +17,13 @@
 
 #include "DialInFlow.h"
 #include "DGDefs.h"
-#include "ModeInitPOST.h"
-#include "ModeTreatment.h"
+#include "DGInterface.h"
+#include "ModeInitPOST.h"
+#include "ModeTreatment.h"
+#include "PersistentAlarm.h"
 #include "OperationModes.h"
 #include "SystemCommMessages.h"
 #include "Timers.h"
-#include "DGInterface.h"
 
 /**
  *  @addtogroup DGInterface
@@ -31,13 +32,20 @@
 
 // ********** private definitions **********
 
-#define START_DG_CMD                        TRUE                ///< Parameter for DG start/stop command function.  True = start.
-#define STOP_DG_CMD                         FALSE               ///< Parameter for DG start/stop command function.  False = stop.
+#define START_DG_CMD                            TRUE                        ///< Parameter for DG start/stop command function.  True = start.
+#define STOP_DG_CMD                             FALSE                       ///< Parameter for DG start/stop command function.  False = stop.
 
-#define RESERVOIR_SETTLE_TIME_MS            5000                ///< Time (in ms) allotted for reservoir to settle (after fill, before drain).
+#define RESERVOIR_SETTLE_TIME_MS                5000                        ///< Time (in ms) allotted for reservoir to settle (after fill, before drain).
 
-#define SIZE_OF_LARGE_LOAD_CELL_AVG         32                  ///< Large load cell moving average has 32 samples.
+#define SIZE_OF_LARGE_LOAD_CELL_AVG             32                          ///< Large load cell moving average has 32 samples.
 
+#define DIALYSATE_TEMP_PERSISTENCE_PERIOD       ( 3 * MS_PER_SECOND )       ///< Persistence period for dialysate temperature alarm.
+
+#define DIALYSATE_TEMP_RECOVERY_TOLERANCE_C     2.0                         ///< Dialysate temperature recovery tolerance in degree C.
+#define DIALYSATE_TEMP_TOLERANCE_C              4.0                         ///< Dialysate temperature tolerance in degree C.
+#define DIALYSATE_TEMP_HIGH_LIMIT_C             42.0                        ///< Dialysate high temperature limit in degree C.
+#define DIALYSATE_TEMP_LOW_LIMIT_C              33.0                        ///< Dialysate low temperature limit in degree C.
+
 /// States of the treatment reservoir management state machine.
 typedef enum TreatmentReservoirMgmt_States
 {
@@ -156,6 +164,9 @@
     lgLoadCellReadingsIdx = 0;
     lgLoadCellReadingsTotal[ DG_RESERVOIR_1 ] = 0.0;
     lgLoadCellReadingsTotal[ DG_RESERVOIR_2 ] = 0.0;
+
+    initPersistentAlarm( ALARM_ID_DIALYSATE_TEMPERATURE_HIGH, DIALYSATE_TEMP_PERSISTENCE_PERIOD, DIALYSATE_TEMP_PERSISTENCE_PERIOD );
+    initPersistentAlarm( ALARM_ID_DIALYSATE_TEMPERATURE_LOW, DIALYSATE_TEMP_PERSISTENCE_PERIOD, DIALYSATE_TEMP_PERSISTENCE_PERIOD );
 }
 
 /*********************************************************************//**
@@ -928,6 +939,46 @@
 
 /*********************************************************************//**
  * @brief
+ * The checkDialysateTemperature function checks the dialysate temperature
+ * reported by DG and alarm if temperature is out of range.
+ * @details Inputs: dgTrimmerTempSet, dgDialysateTemp, dgRedundantDialysateTemp
+ * @details Outputs: alarm if dialysate temperature is out of accepted range
+ * @return none
+ *************************************************************************/
+void checkDialysateTemperature( void )
+{
+    BOOL const dialysateHighTemp = ( ( ( dgDialysateTemp - dgTrimmerTempSet ) > DIALYSATE_TEMP_TOLERANCE_C ) ||
+                                     ( ( dgRedundantDialysateTemp - dgTrimmerTempSet ) > DIALYSATE_TEMP_TOLERANCE_C ) ||
+                                     ( dgDialysateTemp > DIALYSATE_TEMP_HIGH_LIMIT_C ) ||
+                                     ( dgRedundantDialysateTemp > DIALYSATE_TEMP_HIGH_LIMIT_C ) );
+
+    BOOL const dialysateLowTemp = ( ( ( dgTrimmerTempSet - dgDialysateTemp ) > DIALYSATE_TEMP_TOLERANCE_C ) ||
+                                    ( ( dgTrimmerTempSet - dgRedundantDialysateTemp ) > DIALYSATE_TEMP_TOLERANCE_C ) ||
+                                    ( dgDialysateTemp < DIALYSATE_TEMP_LOW_LIMIT_C ) ||
+                                    ( dgRedundantDialysateTemp < DIALYSATE_TEMP_LOW_LIMIT_C ) );
+
+    BOOL const dialysateTempRecovered = fabs( dgDialysateTemp - dgTrimmerTempSet ) < DIALYSATE_TEMP_RECOVERY_TOLERANCE_C ? TRUE : FALSE;
+
+    if ( TRUE == isPersistentAlarmTriggered( ALARM_ID_DIALYSATE_TEMPERATURE_HIGH, dialysateHighTemp ) )
+    {
+        SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DIALYSATE_TEMPERATURE_HIGH, dgTrimmerTempSet, dgDialysateTemp );
+    }
+
+    if ( TRUE == isPersistentAlarmTriggered( ALARM_ID_DIALYSATE_TEMPERATURE_LOW, dialysateLowTemp ) )
+    {
+        SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DIALYSATE_TEMPERATURE_LOW, dgTrimmerTempSet, dgDialysateTemp );
+    }
+
+    if ( ( TRUE == isPersistentAlarmConditionCleared( ALARM_ID_DIALYSATE_TEMPERATURE_LOW, dialysateTempRecovered ) ) ||
+         ( TRUE == isPersistentAlarmConditionCleared( ALARM_ID_DIALYSATE_TEMPERATURE_HIGH, dialysateHighTemp ) ) )
+    {
+        clearAlarm( ALARM_ID_DIALYSATE_TEMPERATURE_HIGH );
+        clearAlarm( ALARM_ID_DIALYSATE_TEMPERATURE_LOW );
+    }
+}
+
+/*********************************************************************//**
+ * @brief
  * The checkDGRestart function checks to see if DG has restarted after started
  * by HD and triggers appropriate alarm.
  * @details Inputs: dgStarted
Index: firmware/App/Controllers/DGInterface.h
===================================================================
diff -u -r6419179374edcd65da462de84e8aeaefb7e20320 -raef738aab88159be8664b91d72b1682a0d0db541
--- firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision 6419179374edcd65da462de84e8aeaefb7e20320)
+++ firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision aef738aab88159be8664b91d72b1682a0d0db541)
@@ -96,6 +96,11 @@
     F32 HtrTrimColdJunc;
     F32 HtrPrimInternal;
     F32 HtrTrimInternal;
+    F32 DGBoardTemp;
+    F32 ResOneLoadCellTemp;
+    F32 ResTwoLoadCellTemp;
+    F32 THDoInternalTemp;
+    F32 TDiInternalTemp;
 } DG_TEMPERATURES_T;
 
 /// Payload record structure for a drain reservoir command message.
@@ -159,6 +164,8 @@
 void handleDGCommandResponse( DG_CMD_RESPONSE_T *dgCmdRespPtr );
 BOOL getDGCommandResponse( U32 commandID, DG_CMD_RESPONSE_T *cmdRespPtr );
 
+void checkDialysateTemperature( void );
+
 BOOL testSetDialOutLoadCellWeightOverride( U32 sensor, F32 value );
 BOOL testResetDialOutLoadCellWeightOverride( U32 sensor );
 
Index: firmware/App/Modes/ModeTreatment.c
===================================================================
diff -u -r4b358e1af8512dd9a0e948ef7c534b6af393b611 -raef738aab88159be8664b91d72b1682a0d0db541
--- firmware/App/Modes/ModeTreatment.c	(.../ModeTreatment.c)	(revision 4b358e1af8512dd9a0e948ef7c534b6af393b611)
+++ firmware/App/Modes/ModeTreatment.c	(.../ModeTreatment.c)	(revision aef738aab88159be8664b91d72b1682a0d0db541)
@@ -417,6 +417,8 @@
         activateAlarmNoData( ALARM_ID_TREATMENT_STOPPED_BY_USER );
     }
 
+    checkDialysateTemperature();
+
     // Treatment mode state machine
     switch ( currentTreatmentState )
     {