diff --git a/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.C b/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.C
index 422e6725de..7a10e2f844 100644
--- a/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.C
+++ b/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.C
@@ -94,19 +94,20 @@ Foam::fv::fixedTemperatureConstraint::fixedTemperatureConstraint
     }
 
 
-    fieldNames_.setSize(1, "energy");
+    // Set the field name to that of the energy field from which the temperature
+    // is obtained
+
+    const basicThermo& thermo =
+        mesh_.lookupObject<basicThermo>("thermophysicalProperties");
+
+    fieldNames_.setSize(1, thermo.he().name());
+
     applied_.setSize(1, false);
 }
 
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
-bool Foam::fv::fixedTemperatureConstraint::alwaysApply() const
-{
-    return true;
-}
-
-
 void Foam::fv::fixedTemperatureConstraint::constrain
 (
     fvMatrix<scalar>& eqn,
@@ -116,34 +117,30 @@ void Foam::fv::fixedTemperatureConstraint::constrain
     const basicThermo& thermo =
         mesh_.lookupObject<basicThermo>("thermophysicalProperties");
 
-    if (eqn.psi().name() == thermo.he().name())
+    switch (mode_)
     {
-        switch (mode_)
+        case tmUniform:
         {
-            case tmUniform:
-            {
-                const scalar t = mesh_.time().value();
-                scalarField Tuni(cells_.size(), Tuniform_->value(t));
-                eqn.setValues(cells_, thermo.he(thermo.p(), Tuni, cells_));
+            const scalar t = mesh_.time().value();
+            scalarField Tuni(cells_.size(), Tuniform_->value(t));
+            eqn.setValues(cells_, thermo.he(thermo.p(), Tuni, cells_));
 
-                break;
-            }
-            case tmLookup:
-            {
-                const volScalarField& T =
-                    mesh().lookupObject<volScalarField>(TName_);
-
-                scalarField Tlkp(T, cells_);
-                eqn.setValues(cells_, thermo.he(thermo.p(), Tlkp, cells_));
-
-                break;
-            }
-            default:
-            {
-                // error handling done by NamedEnum
-            }
+            break;
         }
+        case tmLookup:
+        {
+            const volScalarField& T =
+                mesh().lookupObject<volScalarField>(TName_);
 
+            scalarField Tlkp(T, cells_);
+            eqn.setValues(cells_, thermo.he(thermo.p(), Tlkp, cells_));
+
+            break;
+        }
+        default:
+        {
+            // error handling done by NamedEnum
+        }
     }
 }
 
diff --git a/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.H b/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.H
index 0337ef31e5..7ca1285a7b 100644
--- a/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.H
+++ b/src/fvOptions/constraints/derived/fixedTemperatureConstraint/fixedTemperatureConstraint.H
@@ -136,13 +136,8 @@ public:
 
     // Member Functions
 
-        virtual bool alwaysApply() const;
-
-
-        // Set values directly
-
-            //- Scalar
-            virtual void constrain(fvMatrix<scalar>& eqn, const label fieldI);
+        //- Constrain energy equation to fix the temperature
+        virtual void constrain(fvMatrix<scalar>& eqn, const label fieldI);
 
 
         // IO
diff --git a/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.C b/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.C
index 44969e43f7..dfb6d77b95 100644
--- a/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.C
+++ b/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.C
@@ -166,7 +166,6 @@ Foam::fv::effectivenessHeatExchangerSource::effectivenessHeatExchangerSource
     faceSign_(),
     faceZoneArea_(0)
 {
-
     if (zoneID_ < 0)
     {
         FatalErrorIn
@@ -185,7 +184,14 @@ Foam::fv::effectivenessHeatExchangerSource::effectivenessHeatExchangerSource
             << nl << exit(FatalError);
     }
 
-    fieldNames_.setSize(1, "energy");
+    // Set the field name to that of the energy field from which the temperature
+    // is obtained
+
+    const basicThermo& thermo =
+        mesh_.lookupObject<basicThermo>("thermophysicalProperties");
+
+    fieldNames_.setSize(1, thermo.he().name());
+
     applied_.setSize(1, false);
 
     eTable_.reset(new interpolation2DTable<scalar>(coeffs_));
@@ -196,12 +202,6 @@ Foam::fv::effectivenessHeatExchangerSource::effectivenessHeatExchangerSource
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
-bool Foam::fv::effectivenessHeatExchangerSource::alwaysApply() const
-{
-    return true;
-}
-
-
 void Foam::fv::effectivenessHeatExchangerSource::addSup
 (
     const volScalarField& rho,
@@ -212,11 +212,6 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
     const basicThermo& thermo =
         mesh_.lookupObject<basicThermo>("thermophysicalProperties");
 
-    if (eqn.psi().name() != thermo.he().name())
-    {
-        return;
-    }
-
     const surfaceScalarField Cpf(fvc::interpolate(thermo.Cp()));
 
     const surfaceScalarField& phi =
diff --git a/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.H b/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.H
index b6904701c8..72212d5412 100644
--- a/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.H
+++ b/src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.H
@@ -245,10 +245,7 @@ public:
 
     // Member Functions
 
-        virtual bool alwaysApply() const;
-
-
-        // Add explicit and implicit contributions
+        // Explicit and implicit source
 
             //- Scalar
             virtual void addSup
@@ -265,7 +262,7 @@ public:
             }
 
 
-        // Add explicit and implicit contributions to compressible equation
+        // Explicit and implicit source for compressible equation
 
             //- Scalar
             virtual void addSup
diff --git a/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSourceTemplates.C b/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSourceTemplates.C
index 6487d4021f..ee3481f45f 100644
--- a/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSourceTemplates.C
+++ b/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSourceTemplates.C
@@ -55,13 +55,13 @@ void Foam::fv::solidificationMeltingSource::apply
     if (eqn.psi().dimensions() == dimTemperature)
     {
         // isothermal phase change - only include time derivative
-//        eqn -= L/Cp*(fvc::ddt(rho, alpha1_) + fvc::div(phi, alpha1_));
+        // eqn -= L/Cp*(fvc::ddt(rho, alpha1_) + fvc::div(phi, alpha1_));
         eqn -= L/Cp*(fvc::ddt(rho, alpha1_));
     }
     else
     {
         // isothermal phase change - only include time derivative
-//        eqn -= L*(fvc::ddt(rho, alpha1_) + fvc::div(phi, alpha1_));
+        // eqn -= L*(fvc::ddt(rho, alpha1_) + fvc::div(phi, alpha1_));
         eqn -= L*(fvc::ddt(rho, alpha1_));
     }
 }