diff --git a/eeschema/sim/ngspice.cpp b/eeschema/sim/ngspice.cpp
index d28b142545..c1f416ebc3 100644
--- a/eeschema/sim/ngspice.cpp
+++ b/eeschema/sim/ngspice.cpp
@@ -296,12 +296,12 @@ bool NGSPICE::LoadNetlist( const string& aNetlist )
     lines.push_back( nullptr ); // sentinel, as requested in ngSpice_Circ description
 
     Command( "remcirc" );
-    m_ngSpice_Circ( lines.data() );
+    bool success = !m_ngSpice_Circ( lines.data() );
 
     for( auto line : lines )
         free( line );
 
-    return true;
+    return success;
 }
 
 
@@ -345,8 +345,7 @@ bool NGSPICE::Command( const string& aCmd )
 {
     LOCALE_IO c_locale;               // ngspice works correctly only with C locale
     validate();
-    m_ngSpice_Command( (char*) aCmd.c_str() );
-    return true;
+    return !m_ngSpice_Command( (char*) aCmd.c_str() );
 }
 
 
diff --git a/qa/unittests/eeschema/test_netlist_exporter_spice.cpp b/qa/unittests/eeschema/test_netlist_exporter_spice.cpp
index c47bbea294..d7edd29a9a 100644
--- a/qa/unittests/eeschema/test_netlist_exporter_spice.cpp
+++ b/qa/unittests/eeschema/test_netlist_exporter_spice.cpp
@@ -117,8 +117,8 @@ public:
         //ngspice->Init();
         ngspice->Command( "set ngbehavior=ps" );
         ngspice->Command( "setseed 1" );
-        ngspice->LoadNetlist( netlist.ToStdString() );
-        ngspice->Run();
+        BOOST_REQUIRE( ngspice->LoadNetlist( netlist.ToStdString() ) );
+        BOOST_REQUIRE( ngspice->Run() );
 
         // We need to make sure that the number of points always the same.
         ngspice->Command( "linearize" );