Index: firmware/App/Controllers/DGInterface.c
===================================================================
diff -u -rf6c512d7d0c0a7e37b11423412af8e792438b1d3 -r8acad167bcf7ad07043192007e59d253a5216e3a
--- firmware/App/Controllers/DGInterface.c	(.../DGInterface.c)	(revision f6c512d7d0c0a7e37b11423412af8e792438b1d3)
+++ firmware/App/Controllers/DGInterface.c	(.../DGInterface.c)	(revision 8acad167bcf7ad07043192007e59d253a5216e3a)
@@ -22,6 +22,7 @@
 #include "ModeInitPOST.h"
 #include "ModeTreatment.h"
 #include "ModeTreatmentParams.h"
+#include "PersistentAlarm.h"
 #include "OperationModes.h"
 #include "SystemCommMessages.h"
 #include "Timers.h"
@@ -33,15 +34,22 @@
 
 // ********** 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 MAX_RESERVOIR_VOLUME_ML             1950.0              ///< Maximum reservoir volume.  Switch reservoirs if active reservoir exceeds this volume.
+#define MAX_RESERVOIR_VOLUME_ML                 1950.0              ///< Maximum reservoir volume.  Switch reservoirs if active reservoir exceeds this volume.
 
-#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
 {
@@ -161,6 +169,9 @@
     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 );
 }
 
 /*********************************************************************//**
@@ -1114,6 +1125,47 @@
 
 /*********************************************************************//**
  * @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 ) ||
+                                     ( dgDialysateTemp > DIALYSATE_TEMP_HIGH_LIMIT_C ) );
+
+    BOOL const dialysateLowTemp = ( ( ( dgTrimmerTempSet - dgDialysateTemp ) > DIALYSATE_TEMP_TOLERANCE_C ) ||
+                                    ( dgDialysateTemp < DIALYSATE_TEMP_LOW_LIMIT_C ) );
+
+    BOOL const dialysateTempRecovered = fabs( dgDialysateTemp - dgTrimmerTempSet ) < DIALYSATE_TEMP_RECOVERY_TOLERANCE_C ? TRUE : FALSE;
+
+#ifndef DISABLE_DIALYSATE_TEMP_CHECK
+    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_HIGH, dialysateHighTemp ) )
+    {
+        clearAlarmCondition( ALARM_ID_DIALYSATE_TEMPERATURE_HIGH );
+    }
+
+    if ( TRUE == isPersistentAlarmConditionCleared( ALARM_ID_DIALYSATE_TEMPERATURE_LOW, dialysateTempRecovered ) )
+    {
+        clearAlarmCondition( ALARM_ID_DIALYSATE_TEMPERATURE_LOW );
+    }
+#endif
+}
+
+/*********************************************************************//**
+ * @brief
  * The checkDGRestart function checks to see if DG has restarted after started
  * by HD and triggers appropriate alarm.
  * @details Inputs: dgStarted