Index: firmware/App/Controllers/ROPump.c
===================================================================
diff -u -rc7ea3969643ead419cbfcd34c3cb203c45bcad71 -r39799e6911039979ddec56a4eda7876aa4e0f165
--- firmware/App/Controllers/ROPump.c	(.../ROPump.c)	(revision c7ea3969643ead419cbfcd34c3cb203c45bcad71)
+++ firmware/App/Controllers/ROPump.c	(.../ROPump.c)	(revision 39799e6911039979ddec56a4eda7876aa4e0f165)
@@ -735,11 +735,13 @@
     F32 actualPressure = getMeasuredDGPressure( PRESSURE_SENSOR_RO_PUMP_OUTLET );
 
     // Control at set interval
-    if ( ++roControlTimerCounter >= ROP_CONTROL_INTERVAL && roPumpControlMode == PUMP_CONTROL_MODE_CLOSED_LOOP )
+    if ( ( ++roControlTimerCounter >= ROP_CONTROL_INTERVAL ) && ( roPumpControlMode == PUMP_CONTROL_MODE_CLOSED_LOOP ) )
     {
         if ( actualPressure > targetROPumpMaxPressure )
         {
+            // Reduce the duty cycle and make sure it does not go below 0%
             roPumpDutyCyclePctSet -= ROP_RAMP_DOWN_DUTY_CYCLE_RATIO;
+            roPumpDutyCyclePctSet  = MAX( roPumpDutyCyclePctSet, MIN_RO_PUMP_DUTY_CYCLE );
             resetPIController( PI_CONTROLLER_ID_RO_PUMP_MAX_PRES, roPumpDutyCyclePctSet );
         }
         else