diff --git a/applications/solvers/combustion/fireFoam/pEqn.H b/applications/solvers/combustion/fireFoam/pEqn.H
index f5364ae314..b6f5ef47b1 100644
--- a/applications/solvers/combustion/fireFoam/pEqn.H
+++ b/applications/solvers/combustion/fireFoam/pEqn.H
@@ -5,7 +5,7 @@ surfaceScalarField rhorAUf(rAU.name() + 'f', fvc::interpolate(rho*rAU));
 volVectorField HbyA("HbyA", U);
 HbyA = rAU*UEqn.H();
 
-surfaceScalarField phig(rhorAUf*ghf*fvc::snGrad(rho)*mesh.magSf());
+surfaceScalarField phig(-rhorAUf*ghf*fvc::snGrad(rho)*mesh.magSf());
 
 surfaceScalarField phiHbyA
 (
@@ -15,7 +15,7 @@ surfaceScalarField phiHbyA
         (fvc::interpolate(HbyA) & mesh.Sf())
       + fvc::ddtPhiCorr(rAU, rho, U, phi)
     )
-  - phig
+  + phig
 );
 
 
@@ -37,7 +37,7 @@ while (pimple.correctNonOrthogonal())
     if (pimple.finalNonOrthogonalIter())
     {
         phi = phiHbyA + p_rghEqn.flux();
-        U = HbyA + rAU*fvc::reconstruct((p_rghEqn.flux() - phig)/rhorAUf);
+        U = HbyA + rAU*fvc::reconstruct((p_rghEqn.flux() + phig)/rhorAUf);
         U.correctBoundaryConditions();
     }
 }
diff --git a/applications/solvers/heatTransfer/buoyantBoussinesqSimpleFoam/pEqn.H b/applications/solvers/heatTransfer/buoyantBoussinesqSimpleFoam/pEqn.H
index 61d4358a8a..32076b4dd1 100644
--- a/applications/solvers/heatTransfer/buoyantBoussinesqSimpleFoam/pEqn.H
+++ b/applications/solvers/heatTransfer/buoyantBoussinesqSimpleFoam/pEqn.H
@@ -6,7 +6,7 @@
     HbyA = rAU*UEqn().H();
     UEqn.clear();
 
-    surfaceScalarField phig(rAUf*ghf*fvc::snGrad(rhok)*mesh.magSf());
+    surfaceScalarField phig(-rAUf*ghf*fvc::snGrad(rhok)*mesh.magSf());
 
     surfaceScalarField phiHbyA
     (
@@ -16,7 +16,7 @@
 
     adjustPhi(phiHbyA, U, p_rgh);
 
-    phiHbyA -= phig;
+    phiHbyA += phig;
 
     while (simple.correctNonOrthogonal())
     {
@@ -39,7 +39,7 @@
 
             // Correct the momentum source with the pressure gradient flux
             // calculated from the relaxed pressure
-            U = HbyA - rAU*fvc::reconstruct((phig + p_rghEqn.flux())/rAUf);
+            U = HbyA + rAU*fvc::reconstruct((phig - p_rghEqn.flux())/rAUf);
             U.correctBoundaryConditions();
         }
     }
diff --git a/applications/solvers/heatTransfer/buoyantSimpleFoam/pEqn.H b/applications/solvers/heatTransfer/buoyantSimpleFoam/pEqn.H
index d558f6c217..a7f873c2f1 100644
--- a/applications/solvers/heatTransfer/buoyantSimpleFoam/pEqn.H
+++ b/applications/solvers/heatTransfer/buoyantSimpleFoam/pEqn.H
@@ -9,7 +9,7 @@
     HbyA = rAU*UEqn().H();
     UEqn.clear();
 
-    surfaceScalarField phig(rhorAUf*ghf*fvc::snGrad(rho)*mesh.magSf());
+    surfaceScalarField phig(-rhorAUf*ghf*fvc::snGrad(rho)*mesh.magSf());
 
     surfaceScalarField phiHbyA
     (
@@ -19,7 +19,7 @@
 
     bool closedVolume = adjustPhi(phiHbyA, U, p_rgh);
 
-    phiHbyA -= phig;
+    phiHbyA += phig;
 
     while (simple.correctNonOrthogonal())
     {
@@ -41,7 +41,7 @@
 
             // Correct the momentum source with the pressure gradient flux
             // calculated from the relaxed pressure
-            U = HbyA - rAU*fvc::reconstruct((phig + p_rghEqn.flux())/rhorAUf);
+            U = HbyA + rAU*fvc::reconstruct((phig - p_rghEqn.flux())/rhorAUf);
             U.correctBoundaryConditions();
         }
     }
diff --git a/applications/solvers/lagrangian/reactingParcelFilmFoam/pEqn.H b/applications/solvers/lagrangian/reactingParcelFilmFoam/pEqn.H
index f5364ae314..b6f5ef47b1 100644
--- a/applications/solvers/lagrangian/reactingParcelFilmFoam/pEqn.H
+++ b/applications/solvers/lagrangian/reactingParcelFilmFoam/pEqn.H
@@ -5,7 +5,7 @@ surfaceScalarField rhorAUf(rAU.name() + 'f', fvc::interpolate(rho*rAU));
 volVectorField HbyA("HbyA", U);
 HbyA = rAU*UEqn.H();
 
-surfaceScalarField phig(rhorAUf*ghf*fvc::snGrad(rho)*mesh.magSf());
+surfaceScalarField phig(-rhorAUf*ghf*fvc::snGrad(rho)*mesh.magSf());
 
 surfaceScalarField phiHbyA
 (
@@ -15,7 +15,7 @@ surfaceScalarField phiHbyA
         (fvc::interpolate(HbyA) & mesh.Sf())
       + fvc::ddtPhiCorr(rAU, rho, U, phi)
     )
-  - phig
+  + phig
 );
 
 
@@ -37,7 +37,7 @@ while (pimple.correctNonOrthogonal())
     if (pimple.finalNonOrthogonalIter())
     {
         phi = phiHbyA + p_rghEqn.flux();
-        U = HbyA + rAU*fvc::reconstruct((p_rghEqn.flux() - phig)/rhorAUf);
+        U = HbyA + rAU*fvc::reconstruct((p_rghEqn.flux() + phig)/rhorAUf);
         U.correctBoundaryConditions();
     }
 }