Index: firmware/App/Controllers/Heaters.c
===================================================================
diff -u -r45a4cb0693621b5dc1cf7b1ae237d916856b6c41 -r3efd50bef6d3618b9fed1727aa2bc234ededee2a
--- firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision 45a4cb0693621b5dc1cf7b1ae237d916856b6c41)
+++ firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision 3efd50bef6d3618b9fed1727aa2bc234ededee2a)
@@ -71,7 +71,7 @@
 #define TRIMMER_HEATER_CONTROL_INTERVAL_COUNT                      ( ( 30 * MS_PER_SECOND ) / TASK_GENERAL_INTERVAL )              ///< Trimmer heater control interval count.
 #define TRIMMER_HEATER_MIN_DIALYSATE_FLOWRATE_LPM                  0.00F                                                           ///< Trimmer heater minimum dialysate flow rate in L/min.
 
-#define DELTA_TEMPERATURE_TIME_COSNTANT_C                          8.6F                                                            ///< Delta temperature calculated from time constant.
+#define DELTA_TEMPERATURE_TIME_CONSTANT_C                          8.6F                                                            ///< Delta temperature calculated from time constant.
 #define PRIMARY_HEATER_DUTY_CYCLE_PER_TEMPERATURE_C                0.015F                                                          ///< Primary heaters duty cycle per temperature in C.
 #define DATA_PUBLISH_COUNTER_START_COUNT                           70                                                              ///< Data publish counter start count.
 #define MIN_RO_HEATER_FLOWRATE_LPM                                 0.2F                                                            ///< Minimum target RO heater flow rate in L/min.
@@ -91,7 +91,7 @@
     BOOL startHeaterSignal;                                                                                                        ///< Heater start indication flag.
     BOOL isHeaterOn;                                                                                                               ///< Heater on/off status flag.
     OVERRIDE_F32_T dutyCycle;                                                                                                      ///< Heater duty cycle.
-    F32 targetFlowLPM;                                                                                                             ///< Heater target flow in L/min.
+    F32 targetFlowLPM;                                                                                                             ///< Heater target flow in L/min to calculate the duty cycle.
     F32 nomTargetFlowLPM;                                                                                                          ///< Heater nominal target flow in L/min.
     BOOL hasTargetTempChanged;                                                                                                     ///< Heater target temperature change flag indicator.
     F32  heaterEstGain;                                                                                                            ///< Heater estimation gain during the run.
@@ -526,13 +526,13 @@
     if ( DG_MODE_FILL == opMode )
     {
         // If the previous average fill flow rate is 0, use the nominal target RO flow from the RO pump
-        targetFlowLPM = ( getAvgFillFlowRateLPM() - 0.0F > NEARLY_ZERO ? getAvgFillFlowRateLPM() : getTargetROPumpFlowRateLPM() );
+        targetFlowLPM = ( getAvgFillFlowRateLPM() > NEARLY_ZERO ? getAvgFillFlowRateLPM() : getTargetROPumpFlowRateLPM() );
         dutyCycle     = calculatePrimaryHeaterDutyCycle( targetTemperature, inletTemperature, targetFlowLPM, TRUE );
         state         = HEATER_EXEC_STATE_PRIMARY_CONTROL_TO_TARGET;
     }
     else if ( ( DG_MODE_GENE == opMode ) || ( DG_MODE_DRAI == opMode ) )
     {
-        targetTemperature += DELTA_TEMPERATURE_TIME_COSNTANT_C;
+        targetTemperature += DELTA_TEMPERATURE_TIME_CONSTANT_C;
         targetFlowLPM      = getTargetROPumpFlowRateLPM();
         dutyCycle          = calculatePrimaryHeaterDutyCycle( targetTemperature, inletTemperature, targetFlowLPM, FALSE );
         state              = HEATER_EXEC_STATE_PRIMARY_CONTROL_TO_TARGET;
@@ -783,7 +783,7 @@
  * @details Inputs: none
  * @details Outputs: none
  * @param targetTemperature target temperature of the heater
- * @oaram currentTemperature current inlet temperature of the heater
+ * @param currentTemperature current inlet temperature of the heater
  * @param flow current flow
  * @return calculated duty cycle
  *************************************************************************/
@@ -808,7 +808,7 @@
  * @details Inputs: none
  * @details Outputs: none
  * @param targetTemperature target temperature of the heater
- * @oaram currentTemperature current inlet temperature of the heater
+ * @param currentTemperature current inlet temperature of the heater
  * @param flow current flow
  * @param check efficiency flag to indicate whether to consider heater's
  * efficiency