diff --git a/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriver.C b/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriver.C
index 5e97a4059e..f01b31d70d 100644
--- a/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriver.C
+++ b/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriver.C
@@ -1183,7 +1183,8 @@ void Foam::autoHexMeshDriver::mergePatchFaces()
     meshRefiner.mergePatchFaces
     (
         Foam::cos(45*mathematicalConstant::pi/180.0),
-        Foam::cos(45*mathematicalConstant::pi/180.0)
+        Foam::cos(45*mathematicalConstant::pi/180.0),
+        meshRefinement::addedPatches(globalToPatch_)
     );
 
     if (debug_)
diff --git a/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriverLayers.C b/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriverLayers.C
index 7a6c5ffd7a..8ae25d7b65 100644
--- a/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriverLayers.C
+++ b/src/autoMesh/autoHexMesh/autoHexMeshDriver/autoHexMeshDriverLayers.C
@@ -62,7 +62,15 @@ Foam::label Foam::autoHexMeshDriver::mergePatchFacesUndo
     combineFaces faceCombiner(mesh_, true);
 
     // Get all sets of faces that can be merged
-    labelListList allFaceSets(faceCombiner.getMergeSets(minCos, concaveCos));
+    labelListList allFaceSets
+    (
+        faceCombiner.getMergeSets
+        (
+            minCos,
+            concaveCos,
+            meshRefinement::addedPatches(globalToPatch_)
+        )
+    );
 
     label nFaceSets = returnReduce(allFaceSets.size(), sumOp<label>());
 
diff --git a/src/autoMesh/autoHexMesh/meshRefinement/meshRefinement.H b/src/autoMesh/autoHexMesh/meshRefinement/meshRefinement.H
index c643f4d0f6..1919c860f8 100644
--- a/src/autoMesh/autoHexMesh/meshRefinement/meshRefinement.H
+++ b/src/autoMesh/autoHexMesh/meshRefinement/meshRefinement.H
@@ -607,9 +607,8 @@ public:
             label mergePatchFaces
             (
                 const scalar minCos,
-                const scalar concaveCos
-                //const dictionary& motionDict,
-                //const labelList& globalToPatch
+                const scalar concaveCos,
+                const labelList& patchIDs
             );
 
             //- Remove points not used by any face or points used
diff --git a/src/autoMesh/autoHexMesh/meshRefinement/meshRefinementMerge.C b/src/autoMesh/autoHexMesh/meshRefinement/meshRefinementMerge.C
index d5ba7b052f..0f489029af 100644
--- a/src/autoMesh/autoHexMesh/meshRefinement/meshRefinementMerge.C
+++ b/src/autoMesh/autoHexMesh/meshRefinement/meshRefinementMerge.C
@@ -48,14 +48,43 @@ Class
 Foam::label Foam::meshRefinement::mergePatchFaces
 (
     const scalar minCos,
-    const scalar concaveCos
+    const scalar concaveCos,
+    const labelList& patchIDs
 )
 {
     // Patch face merging engine
     combineFaces faceCombiner(mesh_);
 
+    const polyBoundaryMesh& patches = mesh_.boundaryMesh();
+
+    // Pick up all cells on boundary
+    labelHashSet boundaryCells(mesh_.nFaces()-mesh_.nInternalFaces());
+
+    forAll(patchIDs, i)
+    {
+        label patchI = patchIDs[i];
+
+        const polyPatch& patch = patches[patchI];
+
+        if (!patch.coupled())
+        {
+            forAll(patch, i)
+            {
+                boundaryCells.insert(mesh_.faceOwner()[patch.start()+i]);
+            }
+        }
+    }
+
     // Get all sets of faces that can be merged
-    labelListList mergeSets(faceCombiner.getMergeSets(minCos, concaveCos));
+    labelListList mergeSets
+    (
+        faceCombiner.getMergeSets
+        (
+            minCos,
+            concaveCos,
+            boundaryCells
+        )
+    );
 
     label nFaceSets = returnReduce(mergeSets.size(), sumOp<label>());
 
diff --git a/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.C b/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.C
index 06f63c7964..d74f55d503 100644
--- a/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.C
+++ b/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.C
@@ -293,27 +293,10 @@ Foam::combineFaces::combineFaces
 Foam::labelListList Foam::combineFaces::getMergeSets
 (
     const scalar featureCos,
-    const scalar minConcaveCos
+    const scalar minConcaveCos,
+    const labelHashSet& boundaryCells
 ) const
 {
-    const polyBoundaryMesh& patches = mesh_.boundaryMesh();
-
-    // Pick up all cells on boundary
-    labelHashSet boundaryCells(mesh_.nFaces()-mesh_.nInternalFaces());
-
-    forAll(patches, patchI)
-    {
-        const polyPatch& patch = patches[patchI];
-
-        if (!patch.coupled())
-        {
-            forAll(patch, i)
-            {
-                boundaryCells.insert(mesh_.faceOwner()[patch.start()+i]);
-            }
-        }
-    }
-
     // Lists of faces that can be merged.
     DynamicList<labelList> allFaceSets(boundaryCells.size() / 10);
 
@@ -387,6 +370,34 @@ Foam::labelListList Foam::combineFaces::getMergeSets
 }
 
 
+Foam::labelListList Foam::combineFaces::getMergeSets
+(
+    const scalar featureCos,
+    const scalar minConcaveCos
+) const
+{
+    const polyBoundaryMesh& patches = mesh_.boundaryMesh();
+
+    // Pick up all cells on boundary
+    labelHashSet boundaryCells(mesh_.nFaces()-mesh_.nInternalFaces());
+
+    forAll(patches, patchI)
+    {
+        const polyPatch& patch = patches[patchI];
+
+        if (!patch.coupled())
+        {
+            forAll(patch, i)
+            {
+                boundaryCells.insert(mesh_.faceOwner()[patch.start()+i]);
+            }
+        }
+    }
+
+    return getMergeSets(featureCos, minConcaveCos, boundaryCells);
+}
+
+
 // Gets outside edgeloop as a face
 // - in same order as faces
 // - in mesh vertex labels
diff --git a/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.H b/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.H
index 1b9e29476a..c7b76fa874 100644
--- a/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.H
+++ b/src/dynamicMesh/polyTopoChange/polyTopoChange/combineFaces.H
@@ -152,6 +152,15 @@ public:
 
         // Helper functions
 
+            //- Extract lists of all (non-coupled) boundary faces on selected
+            //  cells that can be merged. Uses getFaceRegions.
+            labelListList getMergeSets
+            (
+                const scalar featureCos,
+                const scalar minConcaveCos,
+                const labelHashSet& boundaryCells
+            ) const;
+
             //- Extract lists of all (non-coupled) boundary faces that can
             //  be merged. Uses getFaceRegions.
             labelListList getMergeSets