Index: firmware/App/Controllers/Heaters.c
===================================================================
diff -u -r9826fc85bd1497ec617ae0e825f78b91972de2b3 -rb49fcf5c295e49f7133ea07398c54b083bf65d49
--- firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision 9826fc85bd1497ec617ae0e825f78b91972de2b3)
+++ firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision b49fcf5c295e49f7133ea07398c54b083bf65d49)
@@ -850,11 +850,16 @@
  *************************************************************************/
 static void monitorHeatersVoltage( void )
 {
-    F32 mainPriVoltage  = getMonitoredLineLevel( MONITORED_LINE_24V_PRIM_HTR_V );
-    // NOTE: it is assumed that the main and small primary heaters have equal voltage since the PWMs are divided into 2
-    // before applying the PWMs to the heaters. Right now, there is no ADC channel available for the small primary
-    // heater so the main primary heater's ADC channel is used for the small primary heater as well.
-    F32 smallPriVoltage = getMonitoredLineLevel( MONITORED_LINE_24V_PRIM_HTR_V );
+    // NOTE: Default to using Primary heater voltage from FPGA
+    F32 mainPriVoltage = getMonitoredLineLevel( MONITORED_LINE_24V_PRIM_HTR_V );;
+#ifndef _RELEASE_
+    if ( SW_CONFIG_ENABLE_VALUE == getSoftwareConfigStatus( SW_CONFIG_ENABLE_V3_SYSTEM ) )
+    {
+        // V3 use CPU based value for Primary, same as Secondary
+        mainPriVoltage  = getMonitoredLineLevel( MONITORED_LINE_24V_SEC_HTR_V );
+    }
+#endif
+    F32 smallPriVoltage = getMonitoredLineLevel( MONITORED_LINE_24V_SEC_HTR_V );
     F32 trimmerVoltage  = getMonitoredLineLevel( MONITORED_LINE_24V_TRIM_HTR_V );
 
     // Voltage to PWM is reverse. If PWM = 0 -> V = 24V