Index: firmware/App/Modes/ModeHeatDisinfect.c
===================================================================
diff -u -r321e3603df2611c653e4bd330f640ab35822fd6d -r97eb7ff2d2b3640ec1d8c80d3749a2741c2b308c
--- firmware/App/Modes/ModeHeatDisinfect.c	(.../ModeHeatDisinfect.c)	(revision 321e3603df2611c653e4bd330f640ab35822fd6d)
+++ firmware/App/Modes/ModeHeatDisinfect.c	(.../ModeHeatDisinfect.c)	(revision 97eb7ff2d2b3640ec1d8c80d3749a2741c2b308c)
@@ -608,9 +608,13 @@
     // Check if flush time has elapsed
     if ( TRUE == didTimeout( stateTimer, FLUSH_DRAIN_WAIT_TIME_MS ) )
     {
+#ifndef DISABLE_HEAT_DISINFECT_CONDUCTIVITY
         // If the inlet temperature and conductivity are in range, move onto the next state
         if ( ( getTemperatureValue( TEMPSENSORS_INLET_PRIMARY_HEATER ) > MIN_INLET_TEMPERATURE_C ) &&
              ( getConductivityValue( CONDUCTIVITYSENSORS_CPI_SENSOR )  <=  MAX_INLET_CONDUCTIVITY_US_PER_CM ) )
+#else
+        if ( TRUE )
+#endif
         {
             setValveState( VPD, VALVE_STATE_OPEN_C_TO_NC );
             setROPumpTargetFlowRateLPM( RO_PUMP_TARGET_FLUSH_FILL_FLOW_RATE_LPM, MAX_RO_PUMP_FLUSH_FILL_PRESSURE_PSI );