Index: firmware/App/Controllers/Heaters.c
===================================================================
diff -u -r53d6550ebd61a9527cbecd507e326cc3079c05ce -r08fd3b3564f6852dec6d2038d37f66b8692fdf44
--- firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision 53d6550ebd61a9527cbecd507e326cc3079c05ce)
+++ firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision 08fd3b3564f6852dec6d2038d37f66b8692fdf44)
@@ -40,8 +40,10 @@
 
 // ********** private definitions **********
 
-#define HEATERS_MAX_DUTY_CYCLE                                     1.00F                                                           ///< Heaters max duty cycle (100%) or ON state
-#define HEATERS_MIN_DUTY_CYCLE                                     0.00F                                                           ///< Heaters minimum duty cycle (0.00%) or OFF state
+#define HEATERS_MAX_DUTY_CYCLE                                     1.00F                                                           ///< Heater max duty cycle (100%) or ON state
+#define HEATERS_MIN_DUTY_CYCLE                                     0.00F                                                           ///< Heater minimum duty cycle (0.00%) or OFF state
+#define HEATER_PWM_FULL_SCALE                                      450                                                             ///< Heater full scale PWM value.
+#define HEATER_PWM_OFFSET                                          25                                                              ///< Heater PWM offset.
 #define HEATER_ON_CTRL_DUTY_CYCLE                                  1.00F                                                           ///< Heater ON control duty cycle.
 #define HEATERS_DISINFECT_DUTY_CYCLE                               0.80F                                                           ///< Heaters disinfect cycle.
 #define HEATERS_DISINFECT_TRANSFER_DUTY_CYCLE                      0.60F                                                           ///< Heaters disinfect transfer duty cycle.
@@ -455,10 +457,16 @@
  *************************************************************************/
 static void setHeaterControl( void )
 {
-    F32 ctrl;
+    F32  ctrl = getHeaterControl();
+    BOOL enable = FALSE;
+    U16  pwm = (U16)( ctrl * (F32)HEATER_PWM_FULL_SCALE + (F32)HEATER_PWM_OFFSET + 0.5F );
 
-    ctrl = getHeaterControl();
-//    setFPGACPrimaryHeaterOnOffControl( (BOOL)ctrl );  // TODO ctrl is F32 - why casting as BOOL????      // TODO - implement FPGA set function
+    if ( ctrl > 0.0F )
+    {
+        enable = TRUE;
+    }
+    setFPGAHeaterEnabled( enable );
+    setFPGAHeaterPWM( pwm );
 }
 
 /*********************************************************************//**
Index: firmware/App/Drivers/BoostPump.c
===================================================================
diff -u -r51d83f99e63d9cb52951097996641cc5b3ddffd7 -r08fd3b3564f6852dec6d2038d37f66b8692fdf44
--- firmware/App/Drivers/BoostPump.c	(.../BoostPump.c)	(revision 51d83f99e63d9cb52951097996641cc5b3ddffd7)
+++ firmware/App/Drivers/BoostPump.c	(.../BoostPump.c)	(revision 08fd3b3564f6852dec6d2038d37f66b8692fdf44)
@@ -74,7 +74,7 @@
     }
 
     // set RO pump to stop
-    setROPumpPWMPct( 0 );
+    setROPumpPWM( 0 );
 
     // TODO set boost pump to stop
 }
@@ -91,7 +91,7 @@
     U32 tach;
 
     // get latest RO pump duty cycle read back from FPGA
-    boostPumpReadDutyCycle[ RO_PUMP ].data = getROPumpPWMPct();
+    boostPumpReadDutyCycle[ RO_PUMP ].data = getROPumpPWM();
 
     // get latest RO pump tachometer count from FPGA and convert to RPM
     tach = (U32)getROPumpTachCount();
@@ -139,7 +139,7 @@
         boostPumpCmdDutyCycle[ pumpID ] = pwm;
         if ( RO_PUMP == pumpID )
         {
-            setROPumpPWMPct( pwm );
+            setROPumpPWM( pwm );
         }
         else
         {
Index: firmware/App/Services/FpgaRO.c
===================================================================
diff -u -ra1907314deab28c20945cd41d2d167924daf2c08 -r08fd3b3564f6852dec6d2038d37f66b8692fdf44
--- firmware/App/Services/FpgaRO.c	(.../FpgaRO.c)	(revision a1907314deab28c20945cd41d2d167924daf2c08)
+++ firmware/App/Services/FpgaRO.c	(.../FpgaRO.c)	(revision 08fd3b3564f6852dec6d2038d37f66b8692fdf44)
@@ -38,6 +38,9 @@
 #define MAX_FPGA_COMM_FAILURES              3                                   ///< FPGA maximum comm failures per MAX_FPGA_COMM_FAILURES_WINDOW_MS
 #define MIN_POWER_ON_TIME_FOR_COMM_FAILS    ( 1 * MS_PER_SECOND )               ///< Allow FPGA comm errors for first second after power-up
 
+#define HEATER_ENABLED                      0x01                                ///< Heater enable bit.
+#define HEATER_DISABLED                     0x00                                ///< Heater disabled.
+
 #define FPGA_CONDUCTIVITY_RESET_BIT             0x01                            ///< Conductivity Sensor reset bit mask.
 #define FPGA_CONDUCTIVITY_INIT_ENABLE_BIT       0x02                            ///< Conductivity Sensor initialization enable bit mask.
 #define FPGA_CONDUCTIVITY_WR_ENABLE_BIT         0x04                            ///< Conductivity Sensor write enable bit mask.
@@ -403,27 +406,29 @@
 
 /*********************************************************************//**
  * @brief
- * The setROPumpPWMPct function sets the RO pump PWM duty cycle.
+ * The setROPumpPWM function sets the RO pump PWM duty cycle.
  * The higher the PWM duty cycle (0..500), the faster the pump will go.
+ * @note PWM values < 5% or > 95% will cause pump to stop so effective
+ * range is actually 25..475.
  * @details \b Inputs: none
  * @details \b Outputs: fpgaActuatorSetPoints.roPumpPWMDutyCyclePct
  * @param pwm PWM duty cycle magnitude
  * @return none
  *************************************************************************/
-void setROPumpPWMPct( U16 pwm )
+void setROPumpPWM( U16 pwm )
 {
    fpgaActuatorSetPoints.roPumpPWMDutyCyclePct = pwm;
 }
 
 /*********************************************************************//**
  * @brief
- * The getROPumpPWMPct function gets a read back from FPGA of RO pump PWM
+ * The getROPumpPWM function gets a read back from FPGA of RO pump PWM
  * duty cycle.
  * @details \b Inputs: fpgaSensorReadings.roPumpPWMReadback
  * @details \b Outputs: none
  * @return measured speed (RPM) of the RO pump
  *************************************************************************/
-U16 getROPumpPWMPct( void )
+U16 getROPumpPWM( void )
 {
     return fpgaSensorReadings.roPumpPWMReadback;
 }
@@ -443,6 +448,42 @@
 
 /*********************************************************************//**
  * @brief
+ * The setFPGAHeaterEnabled function sets the heater enable on or off.
+ * @details \b Inputs: none
+ * @details \b Outputs: fpgaActuatorSetPoints.heaterControl
+ * @param enable Flag indicating whether to enable or disable the heater.
+ * @return none
+ *************************************************************************/
+void setFPGAHeaterEnabled( BOOL enable )
+{
+    if ( TRUE == enable )
+    {
+        fpgaActuatorSetPoints.heaterControl = HEATER_ENABLED;
+    }
+    else
+    {
+        fpgaActuatorSetPoints.heaterControl = HEATER_DISABLED;
+    }
+}
+
+/*********************************************************************//**
+ * @brief
+ * The setFPGAHeaterPWM function sets the heater PWM duty cycle.
+ * The higher the PWM duty cycle (0..500), the faster the pump will go.
+ * @note PWM values < 5% or > 95% will cause heater to go off so effective
+ * range is actually 25..475.
+ * @details \b Inputs: none
+ * @details \b Outputs: fpgaActuatorSetPoints.heaterPWMDutyCyclePct
+ * @param pwm PWM duty cycle magnitude
+ * @return none
+ *************************************************************************/
+void setFPGAHeaterPWM( U16 pwm )
+{
+    fpgaActuatorSetPoints.heaterPWMDutyCyclePct = pwm;
+}
+
+/*********************************************************************//**
+ * @brief
  * The getFPGAPRiRawPressure function gets the PRi pressure reading.
  * @details \b Inputs: fpgaSensorReadings.pressurePri
  * @details \b Outputs: none
Index: firmware/App/Services/FpgaRO.h
===================================================================
diff -u -ra1907314deab28c20945cd41d2d167924daf2c08 -r08fd3b3564f6852dec6d2038d37f66b8692fdf44
--- firmware/App/Services/FpgaRO.h	(.../FpgaRO.h)	(revision a1907314deab28c20945cd41d2d167924daf2c08)
+++ firmware/App/Services/FpgaRO.h	(.../FpgaRO.h)	(revision 08fd3b3564f6852dec6d2038d37f66b8692fdf44)
@@ -45,10 +45,13 @@
 U16  getFPGAValveStates( void );
 
 void setROPumpEnable( BOOL enable );
-void setROPumpPWMPct( U16 pwm );
-U16  getROPumpPWMPct( void );
+void setROPumpPWM( U16 pwm );
+U16  getROPumpPWM( void );
 U16  getROPumpTachCount( void );
 
+void setFPGAHeaterEnabled( BOOL enable );
+void setFPGAHeaterPWM( U16 pwm );
+
 S16  getFPGAPRiRawPressure( void );
 S16  getFPGAPRiRawTemperature( void );
 U08  getFPGAPRiReadCount( void );