diff --git a/applications/solvers/heatTransfer/chtMultiRegionFoam/fluid/createFluidMeshes.H b/applications/solvers/heatTransfer/chtMultiRegionFoam/fluid/createFluidMeshes.H
index 9ded78bb7a..0e76c92caf 100644
--- a/applications/solvers/heatTransfer/chtMultiRegionFoam/fluid/createFluidMeshes.H
+++ b/applications/solvers/heatTransfer/chtMultiRegionFoam/fluid/createFluidMeshes.H
@@ -1,4 +1,7 @@
-    const wordList fluidNames(rp["fluid"]);
+    const wordList fluidNames
+    (
+        rp.found("fluid") ? rp["fluid"] : wordList(0)
+    );
 
     PtrList<fvMesh> fluidRegions(fluidNames.size());
 
diff --git a/applications/solvers/heatTransfer/chtMultiRegionFoam/solid/createSolidMeshes.H b/applications/solvers/heatTransfer/chtMultiRegionFoam/solid/createSolidMeshes.H
index 101d98ebe6..bc08644911 100644
--- a/applications/solvers/heatTransfer/chtMultiRegionFoam/solid/createSolidMeshes.H
+++ b/applications/solvers/heatTransfer/chtMultiRegionFoam/solid/createSolidMeshes.H
@@ -1,10 +1,13 @@
-    const wordList solidsNames(rp["solid"]);
+    const wordList solidNames
+    (
+        rp.found("solid") ? rp["solid"] : wordList(0)
+    );
 
-    PtrList<fvMesh> solidRegions(solidsNames.size());
+    PtrList<fvMesh> solidRegions(solidNames.size());
 
-    forAll(solidsNames, i)
+    forAll(solidNames, i)
     {
-        Info<< "Create solid mesh for region " << solidsNames[i]
+        Info<< "Create solid mesh for region " << solidNames[i]
             << " for time = " << runTime.timeName() << nl << endl;
 
         solidRegions.set
@@ -14,7 +17,7 @@
             (
                 IOobject
                 (
-                    solidsNames[i],
+                    solidNames[i],
                     runTime.timeName(),
                     runTime,
                     IOobject::MUST_READ