Index: firmware/App/Modes/ModeFill.c
===================================================================
diff -u -r6835f89b10dfac6fa12d27b357a85670fdcde088 -r83e2e219e3a8aeea65d6dbaeea15c9498427fd78
--- firmware/App/Modes/ModeFill.c	(.../ModeFill.c)	(revision 6835f89b10dfac6fa12d27b357a85670fdcde088)
+++ firmware/App/Modes/ModeFill.c	(.../ModeFill.c)	(revision 83e2e219e3a8aeea65d6dbaeea15c9498427fd78)
@@ -55,6 +55,9 @@
 
 #define CONDUCTIVITY_ERROR_PERSISTENCE_PERIOD_MS        ( 5 * MS_PER_SECOND )                       ///< Persistence period for conductivity error.
 
+#define MAXIMUM_DIALYSATE_TEMPERATURE                   42.0                                        ///< Maximum allowed dialysate temperature in degree C.
+#define MINIMUM_DIALYSATE_TEMPERATURE                   33.0                                        ///< Minimum allowed dialysate temperature in degree C.
+
 /// Multiplier to convert flow (L/min) into volume (mL) for period of general task interval.
 static const F32 RO_FLOW_INTEGRATOR = ( ( ML_PER_LITER * TASK_GENERAL_INTERVAL ) / ( SEC_PER_MIN * MS_PER_SECOND ) );
 
@@ -71,6 +74,7 @@
 
 static BOOL isWaterQualityGood( void );
 static BOOL checkDialysateConductivity( void );
+static BOOL checkDialysateTemperature( void );
 static DG_FILL_MODE_STATE_T handleCheckInletWaterState( void );
 static DG_FILL_MODE_STATE_T handleBicarbPumpCheckState( void );
 static DG_FILL_MODE_STATE_T handleAcidPumpCheckState( void );
@@ -238,6 +242,27 @@
 
 /*********************************************************************//**
  * @brief
+ * The checkDialysateTemperature function checks dialysate temperature after
+ * it gets heated up by primary heater.
+ * @details Inputs: TPo temperature value
+ * @details Outputs: None
+ * @return TRUE if dialysate temperature is good, otherwise FALSE
+ *************************************************************************/
+static BOOL checkDialysateTemperature( void )
+{
+    BOOL result = FALSE;
+    F32 const dialysateTemp = getTemperatureValue( TEMPSENSORS_OUTLET_PRIMARY_HEATER );
+
+    if ( ( MINIMUM_DIALYSATE_TEMPERATURE <= dialysateTemp ) && ( dialysateTemp <= MAXIMUM_DIALYSATE_TEMPERATURE ) )
+    {
+        result = TRUE;
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
  * The handleCheckInletWaterState function checks for inlet water quality
  * before jumping to dialysate production state.
  * @details Inputs: Temperature and conductivity alarms
@@ -350,9 +375,8 @@
 
     handleDialysateMixing();
 
-    // TODO - transition when temperature and mix is in range
 #ifndef DISABLE_DIALYSATE_CHECK
-    if ( TRUE == checkDialysateConductivity() )
+    if ( ( TRUE == checkDialysateConductivity() ) && ( TRUE == checkDialysateTemperature() ) )
 #endif
     {
         setValveState( VPO, VALVE_STATE_FILL_C_TO_NC );
@@ -378,8 +402,7 @@
 
     handleDialysateMixing();
 
-    // TODO - transition back when temperature or mix out of range
-    if ( FALSE == checkDialysateConductivity() )
+    if ( ( FALSE == checkDialysateConductivity() ) || ( FALSE == checkDialysateTemperature() ) )
     {
 #ifndef DISABLE_DIALYSATE_CHECK
         setValveState( VPO, VALVE_STATE_NOFILL_C_TO_NO );