Index: firmware/App/Services/Reservoirs.c
===================================================================
diff -u -r3012a339084bbb5fa796d41680bc0c48bdc9f691 -r3efd50bef6d3618b9fed1727aa2bc234ededee2a
--- firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 3012a339084bbb5fa796d41680bc0c48bdc9f691)
+++ firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 3efd50bef6d3618b9fed1727aa2bc234ededee2a)
@@ -55,8 +55,6 @@
 #define DATA_PUBLISH_COUNTER_START_COUNT          5                                               ///< Data publish counter start count.
 #define NUM_OF_ACID_AND_BICARB_NV_DATA_TO_CHECK   1                                               ///< Number of acid and bicarb non-volatile data to check.
 
-#define TARGET_TEMP_IN_FILLS_LESS_THAN_UF_VOL_C    45.0F                                          ///< Target temperature in fill less than the ultrafilter's volume in C.
-
 // ********** private data **********
 
 /// Heaters temperature calculation data structure
@@ -75,6 +73,7 @@
     F32 tempRsrvr0ActualTrimmer;                                                                  ///< Temperature actual reservoir in C.
     F32 tempFillMixAvgTrimmer;                                                                    ///< Temperature fill mix average trimmer in C.
     F32 tempRsrvrEndFillTrimmer;                                                                  ///< Temperature reservoir end fill trimmer in C.
+    BOOL usePriTargetTempEquation;                                                                ///< Use primary heater target temperature enquation flag.
 } HEATERS_TEMPERATURE_CALC_DATA_T;
 
 /// Reservoirs previous status
@@ -626,6 +625,7 @@
     heatersTempCalc.timeReservoirFillMS        = params.timeReservoirFillMS;
     heatersTempCalc.tempTargetTrimmer          = params.trimmerTargetTemperature;
     heatersTempCalc.flowTargetDialysateLPM     = params.dialysateFlowLPM;
+    heatersTempCalc.usePriTargetTempEquation   = params.usePriTargetTempEquation;
 
     // Check if this is the first time that the dialysate heating parameters are set in DG
     if ( TRUE == isThisTheFirstCycle )
@@ -645,7 +645,7 @@
  *************************************************************************/
 F32 getPrimaryHeaterTargetTemperature( void )
 {
-    F32 tempTargetC      = TARGET_TEMP_IN_FILLS_LESS_THAN_UF_VOL_C;
+    F32 tempTargetC      = heatersTempCalc.tempTargetTrimmer;
     F32 priTargetTempC   = 0.0F;
     F32 targetFillVolML  = getTargetFillVolumeML();
     F32 UFTimeConstant   = 0.0F;
@@ -657,7 +657,7 @@
     F32 tgtBicarbFlowLPM = getConcentratePumpTargetFlowMLPM( CONCENTRATEPUMPS_CP2_BICARB ) / ML_PER_LITER;
     F32 tgtTotalFlowLPM  = targetROFlowLPM + tgtAcidFlowLPM + tgtBicarbFlowLPM;
 
-    if ( targetFillVolML > heatingConstsCalRecord.ultrafilterVolmL )
+    if ( TRUE == heatersTempCalc.usePriTargetTempEquation )
     {
         if ( FALSE == isThisTheFirstFill() )
         {