Index: firmware/App/Modes/ModeTreatmentParams.c
===================================================================
diff -u -rabd0f05c634651fec6615c0f8cb75af166610cc3 -r8466e63f95f65a3ffb18c3af85ac99328e41167b
--- firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision abd0f05c634651fec6615c0f8cb75af166610cc3)
+++ firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision 8466e63f95f65a3ffb18c3af85ac99328e41167b)
@@ -132,6 +132,8 @@
     treatParamsRejected = FALSE;
     treatmentCancelled = FALSE;
 
+    setTreatmentParameterF32( TREATMENT_PARAM_UF_VOLUME, 0.0 );
+
     // Set user alarm recovery actions allowed in this mode
     setAlarmUserActionEnabled( ALARM_USER_ACTION_RESUME, FALSE );
     setAlarmUserActionEnabled( ALARM_USER_ACTION_RINSEBACK, FALSE );
@@ -401,16 +403,13 @@
 {
     BOOL accepted = FALSE;
     REQUEST_REJECT_REASON_CODE_T rejReason = REQUEST_REJECT_REASON_NONE;
-    F32  uFVolumeL = uFVolumeMl / (F32)ML_PER_LITER;
+    F32 uFVolumeL = uFVolumeMl / (F32)ML_PER_LITER;
 
     // Validate given UF volume
     accepted = setTreatmentParameterF32( TREATMENT_PARAM_UF_VOLUME, uFVolumeL );
-    if ( FALSE == accepted )
+
+    if ( TRUE == accepted )
     {
-        rejReason = REQUEST_REJECT_REASON_UF_VOLUME_OUT_OF_RANGE;
-    }
-    else
-    {
         U32 treatmentDuration = getTreatmentParameterU32( TREATMENT_PARAM_TREATMENT_DURATION );
 
         if ( treatmentDuration > 0 )
@@ -429,6 +428,10 @@
             rejReason = REQUEST_REJECT_REASON_TREATMENT_TIME_LESS_THAN_MINIMUM;
         }
     }
+    else
+    {
+        rejReason = REQUEST_REJECT_REASON_UF_VOLUME_OUT_OF_RANGE;
+    }
 
     // Respond to set treatment parameters request message
     uFVolumeL = getTreatmentParameterF32( TREATMENT_PARAM_UF_VOLUME );