Index: sources/gui/qml/pages/pretreatment/create/PreTreatmentCreate.qml
===================================================================
diff -u -rdf4a8ce65fc27ab5842327810ba4545d0a2f8fcb -r20639e283efe066d113c8b81630d89e4f8e82902
--- sources/gui/qml/pages/pretreatment/create/PreTreatmentCreate.qml	(.../PreTreatmentCreate.qml)	(revision df4a8ce65fc27ab5842327810ba4545d0a2f8fcb)
+++ sources/gui/qml/pages/pretreatment/create/PreTreatmentCreate.qml	(.../PreTreatmentCreate.qml)	(revision 20639e283efe066d113c8b81630d89e4f8e82902)
@@ -38,7 +38,7 @@
         _heparinBolusVolume     .active      && _heparinBolusVolume     .          valid &&
         _heparinStopTime        .active      && _heparinStopTime        .          valid &&
         _salineBolus            .active      && _salineBolus            .          valid &&
-        _heparinType            .active      &&
+        _heparinType._heparinTypeActive      &&
         _acidConcentrate        .active      &&
         _bicarbonateConcentrate .active      &&
         _dialyzerType           .active      &&
@@ -409,10 +409,20 @@
             }
 
             GridSelection { id  : _heparinType
+                readonly property bool _heparinTypeActive : (enabled && active) || (!enabled)
+
                 objectName      : "_heparinTypeRect"
                 title           : qsTr("Heparin Type")
                 labels          : vTreatmentRanges.heparinTypeOptions
                 onClicked       :{vTreatmentCreate.heparinType = curIndex               ; vTreatmentCreate.heparinTypeSet               = true; }
+                enabled         : _heparinDispensingRateSwitch.checked || _heparinBolusVolumeSwitch.checked
+                onEnabledChanged: {
+                    if (!enabled) {
+                        // set disabled value
+                        vTreatmentCreate.heparinType    = -1
+                        vTreatmentCreate.heparinTypeSet = false
+                    }
+                }
 
                 valid               : ! vTreatmentCreate.heparinTypeRejectReason
                 onCurIndexChanged   :   vTreatmentCreate.heparinTypeRejectReason            = Variables.noRejectReason