diff --git a/src/regionModels/surfaceFilmModels/thermoSingleLayer/thermoSingleLayer.C b/src/regionModels/surfaceFilmModels/thermoSingleLayer/thermoSingleLayer.C
index ed59cb375792432a20e05dc774ccc93cf85a855f..d15f78aff58fc74cc36ee9b247d678c0eea3717f 100644
--- a/src/regionModels/surfaceFilmModels/thermoSingleLayer/thermoSingleLayer.C
+++ b/src/regionModels/surfaceFilmModels/thermoSingleLayer/thermoSingleLayer.C
@@ -265,12 +265,12 @@ tmp<fvScalarMatrix> thermoSingleLayer::q(volScalarField& hs) const
     return
     (
         // Heat-transfer to the primary region
-      - fvm::Sp(alpha_*htcs_->h()/Cp_, hs)
-      + alpha_*htcs_->h()*(hs/Cp_ - T_ + TPrimary_)
+      - fvm::Sp(htcs_->h()/Cp_, hs)
+      + htcs_->h()*(hs/Cp_ + alpha_*(TPrimary_ - T_))
 
         // Heat-transfer to the wall
-      - fvm::Sp(alpha_*htcw_->h()/Cp_, hs)
-      + alpha_*htcw_->h()*(hs/Cp_ - T_ + Tw_)
+      - fvm::Sp(htcw_->h()/Cp_, hs)
+      + htcw_->h()*(hs/Cp_ + alpha_*(Tw_- T_))
     );
 }