diff --git a/src/TurbulenceModels/compressible/turbulentFluidThermoModels/derivedFvPatchFields/externalWallHeatFluxTemperature/externalWallHeatFluxTemperatureFvPatchScalarField.C b/src/TurbulenceModels/compressible/turbulentFluidThermoModels/derivedFvPatchFields/externalWallHeatFluxTemperature/externalWallHeatFluxTemperatureFvPatchScalarField.C
index 617860d36..8026e6720 100644
--- a/src/TurbulenceModels/compressible/turbulentFluidThermoModels/derivedFvPatchFields/externalWallHeatFluxTemperature/externalWallHeatFluxTemperatureFvPatchScalarField.C
+++ b/src/TurbulenceModels/compressible/turbulentFluidThermoModels/derivedFvPatchFields/externalWallHeatFluxTemperature/externalWallHeatFluxTemperatureFvPatchScalarField.C
@@ -95,7 +95,7 @@ externalWallHeatFluxTemperatureFvPatchScalarField
     temperatureCoupledBase(patch(), dict),
     mode_(operationModeNames.read(dict.lookup("mode"))),
     Q_(0),
-    Ta_(Function1<scalar>::New("Ta", dict)),
+    Ta_(),
     relaxation_(dict.lookupOrDefault<scalar>("relaxation", 1)),
     emissivity_(dict.lookupOrDefault<scalar>("emissivity", 0)),
     qrRelaxation_(dict.lookupOrDefault<scalar>("qrRelaxation", 1)),
@@ -120,6 +120,7 @@ externalWallHeatFluxTemperatureFvPatchScalarField
         case fixedHeatTransferCoeff:
         {
             h_ = scalarField("h", dict, p.size());
+            Ta_ = Function1<scalar>::New("Ta", dict);
 
             if (dict.found("thicknessLayers"))
             {