Index: firmware/App/Controllers/Ultrafiltration.c
===================================================================
diff -u -rf2b23abd44f71103b3ef6b0a96f18cc82d263735 -r25dbc6221b63e20fe61b2af0ce9c9f56bf13e807
--- firmware/App/Controllers/Ultrafiltration.c	(.../Ultrafiltration.c)	(revision f2b23abd44f71103b3ef6b0a96f18cc82d263735)
+++ firmware/App/Controllers/Ultrafiltration.c	(.../Ultrafiltration.c)	(revision 25dbc6221b63e20fe61b2af0ce9c9f56bf13e807)
@@ -19,6 +19,7 @@
 #include "Messaging.h"
 #include "OperationModes.h"
 #include "TaskGeneral.h"
+#include "Temperature.h"
 #include "TDInterface.h"
 #include "TestSupport.h"
 #include "Ultrafiltration.h"
@@ -31,12 +32,18 @@
 // ********** private definitions **********
 
 #define UF_DATA_PUBLISH_INTERVAL            ( 1000 / TASK_GENERAL_INTERVAL )                    ///< Interval (ms/task time) at which the ultrafiltration data published.
+#define UF_COMPENSATION_PERIOD              ( 2 * SEC_PER_MIN * MS_PER_SECOND )                 ///< Interval at which the ultrafiltration compenstaion executed.
+#define UF_COMP_INTERVAL                    ( UF_COMPENSATION_PERIOD / TASK_GENERAL_INTERVAL )  ///< Interval (ms/task time) at which the peroidic ultrafiltration compensation calculated.
+#define COMP_SLOPE                          -0.000376F                                          ///< UF Temperature compensation slope factor
+#define COMP_INTERCEPT                      1.007269F                                           ///< UF temperature compensation intercept factor
 #define ZERO_RATE                           0.0F                                                ///< Zero value.
 
 // ********** private data **********
 
 static UF_EXEC_STATE_T ufExecState;                                                             ///< Current ultrafiltration executive state.
 static BOOL isUltrafiltrationRequested;                                                         ///< Flag indicating ultrafiltration request.
+static U32 currentUFCompCounter;                                                                ///< Counter (in task interval) to initiate the periodic ultrafiltration temperature compensation.
+static F32 compUFrate;                                                                          ///< compensated UF rate
 static U32 ufDataPublicationTimerCounter;                                                       ///< Used to schedule ultrafiltration data publication to CAN bus.
 static OVERRIDE_U32_T ufDataPublishInterval;                                                    ///< Ultrafiltration data publish interval.
 
@@ -45,6 +52,7 @@
 static UF_EXEC_STATE_T handleUFRunningState( void );
 static UF_EXEC_STATE_T handleUFPausedState( void );
 static void updateUFRequest( void );
+static void UpdateUFCompensation( void );
 static void publishUltrafiltrationData( void );
 
 /*********************************************************************//**
@@ -62,6 +70,8 @@
     ufDataPublishInterval.ovInitData        = 0;
     ufDataPublishInterval.override          = OVERRIDE_RESET;
     isUltrafiltrationRequested              = FALSE;
+    currentUFCompCounter                    = 0;
+    compUFrate                              = getTDUFRate();
     ufDataPublicationTimerCounter           = 0;
 }
 
@@ -92,6 +102,9 @@
     // Calculate UF volume and determine UF pause/run
     updateUFRequest();
 
+    // Compensate balancing error at defined interval
+    UpdateUFCompensation();
+
     // execute current ultrafiltration exec state
     switch ( ufExecState )
     {
@@ -129,7 +142,7 @@
 
     if ( TRUE == isUltrafiltrationRequested )
     {
-        setConcentratePumpTargetSpeed( D76_PUMP, getTDUFRate(), DOSING_CONT_VOLUME );
+        setConcentratePumpTargetSpeed( D76_PUMP, compUFrate, DOSING_CONT_VOLUME );
         requestConcentratePumpOn( D76_PUMP );
 
         //Tranistion to run state
@@ -159,7 +172,7 @@
     else
     {
         // Get the updated rate if there is any change
-        setConcentratePumpTargetSpeed( D76_PUMP, getTDUFRate(), DOSING_CONT_VOLUME );
+        setConcentratePumpTargetSpeed( D76_PUMP, compUFrate, DOSING_CONT_VOLUME );
     }
 
     return state;
@@ -189,6 +202,34 @@
 
 /*********************************************************************//**
  * @brief
+ * The UpdateUFCompensation function updates the ultrafiltration rate
+ * based on the dialysate temperature compensation.
+ * @details \b Inputs: D4 and D50 temperature
+ * @details \b Outputs: updated UF rate
+ * @return none.
+ *************************************************************************/
+static void UpdateUFCompensation( void )
+{
+    if ( ++currentUFCompCounter >= UF_COMP_INTERVAL )
+    {
+        F32 freshDensity            = ( COMP_SLOPE * getD4AverageTemperature() ) + COMP_INTERCEPT;         // Fresh side dialysate density
+        F32 spentDensity            = ( COMP_SLOPE * getD50AverageTemperature() ) + COMP_INTERCEPT;        // spent side dialysate density
+        F32 compFreshFlowrate       = getTDDialysateFlowrate() * freshDensity;                             // Qd * fresh density
+        F32 compSpentFlowrate       = getTDDialysateFlowrate() * spentDensity;                             // Qd * spent density
+        F32 balancingError          = compFreshFlowrate - compSpentFlowrate;                               // Error in g/min
+
+        //Update compensate UF rate with the balancing chamber error
+        if ( getTDUFRate() > ZERO_RATE )
+        {
+            compUFrate = getTDUFRate() + balancingError;
+        }
+
+        currentUFCompCounter = 0;
+    }
+}
+
+/*********************************************************************//**
+ * @brief
  * The getCurrentUFExecState function returns the current state
  * of the ultrafiltration.
  * @details \b Inputs: ufExecState
@@ -218,6 +259,7 @@
 
         data.ufExecState                = (U32)ufExecState;
         data.ufRate                     = getTDUFRate();
+        data.compUFrate                 = compUFrate;
         data.isUFRequested              = (U32)isUltrafiltrationRequested;
 
         broadcastData( MSG_ID_DD_UF_DATA, COMM_BUFFER_OUT_CAN_DD_BROADCAST, (U08*)&data, sizeof( UF_DATA_T ) );