diff --git a/applications/solvers/lagrangian/reactingParcelFoam/pEqn.H b/applications/solvers/lagrangian/reactingParcelFoam/pEqn.H
index 0344f9b1a41a170b197e75500146a4e57e6e8e49..81f5e5447adcadc497f7dc868e9ee2c146a344a5 100644
--- a/applications/solvers/lagrangian/reactingParcelFoam/pEqn.H
+++ b/applications/solvers/lagrangian/reactingParcelFoam/pEqn.H
@@ -23,6 +23,7 @@ surfaceScalarField phiHbyA
   + phig
 );
 
+fvc::makeRelative(phiHbyA, rho, U);
 MRF.makeRelative(fvc::interpolate(rho), phiHbyA);
 
 // Update the pressure BCs to ensure flux consistency