diff --git a/qt-ui/mainwindow.cpp b/qt-ui/mainwindow.cpp
index 0c042cae5..69ffdb224 100644
--- a/qt-ui/mainwindow.cpp
+++ b/qt-ui/mainwindow.cpp
@@ -40,6 +40,8 @@ MainWindow::MainWindow() : ui(new Ui::MainWindow())
 	ui->setupUi(this);
 	setWindowIcon(QIcon(":subsurface-icon"));
 	connect(ui->ListWidget, SIGNAL(currentDiveChanged(int)), this, SLOT(current_dive_changed(int)));
+	connect(PreferencesDialog::instance(), SIGNAL(settingsChanged()), this, SLOT(readSettings()));
+	connect(PreferencesDialog::instance(), SIGNAL(settingsChanged()), ui->ProfileWidget, SLOT(refresh()));
 	ui->mainErrorMessage->hide();
 	ui->ProfileWidget->setFocusProxy(ui->ListWidget);
 	ui->ListWidget->reload();
@@ -355,11 +357,11 @@ void MainWindow::readSettings()
 
 	settings.endGroup();
 	settings.beginGroup("Units");
-	GET_UNIT(v, "feet", length, units::FEET, units::METERS);
-	GET_UNIT(v, "psi", pressure, units::PSI, units::BAR);
-	GET_UNIT(v, "cuft", volume, units::CUFT, units::LITER);
-	GET_UNIT(v, "fahrenheit", temperature, units::FAHRENHEIT, units::CELSIUS);
-	GET_UNIT(v, "lbs", weight, units::LBS, units::KG);
+	GET_UNIT(v, "length", length, units::FEET, units::METERS);
+	GET_UNIT(v, "pressure", pressure, units::PSI, units::BAR);
+	GET_UNIT(v, "volume", volume, units::CUFT, units::LITER);
+	GET_UNIT(v, "temperature", temperature, units::FAHRENHEIT, units::CELSIUS);
+	GET_UNIT(v, "weight", weight, units::LBS, units::KG);
 	settings.endGroup();
 	settings.beginGroup("DisplayListColumns");
 	GET_BOOL(v, "CYLINDER", prefs.visible_cols.cylinder);
@@ -437,11 +439,11 @@ void MainWindow::writeSettings()
 			settings.setValue(QString("colwidth%1").arg(i), ui->ListWidget->columnWidth(i));
 	settings.endGroup();
 	settings.beginGroup("Units");
-	SAVE_VALUE("feet", units.length);
-	SAVE_VALUE("psi", units.pressure);
-	SAVE_VALUE("cuft", units.volume);
-	SAVE_VALUE("fahrenheit", units.temperature);
-	SAVE_VALUE("lbs", units.weight);
+	SAVE_VALUE("length", units.length);
+	SAVE_VALUE("pressure", units.pressure);
+	SAVE_VALUE("volume", units.volume);
+	SAVE_VALUE("temperature", units.temperature);
+	SAVE_VALUE("weight", units.weight);
 	settings.endGroup();
 	settings.beginGroup("DisplayListColumns");
 	SAVE_VALUE("TEMPERATURE", visible_cols.temperature);
diff --git a/qt-ui/mainwindow.h b/qt-ui/mainwindow.h
index a5b1a9b48..2366617c6 100644
--- a/qt-ui/mainwindow.h
+++ b/qt-ui/mainwindow.h
@@ -85,6 +85,9 @@ private Q_SLOTS:
 protected:
 	void closeEvent(QCloseEvent *);
 
+public Q_SLOTS:
+	void readSettings();
+
 private:
 	Ui::MainWindow *ui;
 	QAction *actionNextDive;
@@ -92,7 +95,6 @@ private:
 
 	QString filter();
 	bool askSaveChanges();
-	void readSettings();
 	void writeSettings();
 	void redrawProfile();
 	void file_save();
diff --git a/qt-ui/preferences.cpp b/qt-ui/preferences.cpp
index 1c38fe317..3e684d88a 100644
--- a/qt-ui/preferences.cpp
+++ b/qt-ui/preferences.cpp
@@ -21,6 +21,7 @@ PreferencesDialog::PreferencesDialog(QWidget* parent, Qt::WindowFlags f) : QDial
 	QSettings s;
 
 	// Graph
+	s.beginGroup("TecDetails");
 	ui->calculated_ceiling->setChecked(B(show_calculated_ceiling));
 	ui->phe->setChecked(B(show_phe));
 	ui->po2->setChecked(B(show_po2));
@@ -34,39 +35,44 @@ PreferencesDialog::PreferencesDialog(QWidget* parent, Qt::WindowFlags f) : QDial
 	ui->increment_3m->setChecked(B(show_3m_increments));
 	ui->gflow->setValue(D(gflow));
 	ui->gfhigh->setValue(D(gfhigh));
+	s.endGroup();
 
 	// Units
+	s.beginGroup("Units");
 	bool value = s.value("units_metric").toBool();
 	ui->metric->setChecked(value);
 	ui->imperial->setChecked(!value);
 
-	value = s.value("units_celcius").toBool();
-	ui->celsius->setChecked( value);
-	ui->fahrenheit->setChecked( !value);
+	int unit = s.value("temperature").toInt();
+	ui->celsius->setChecked(unit == units::CELSIUS);
+	ui->fahrenheit->setChecked(unit == units::FAHRENHEIT);
 
-	value = s.value("units_meters").toBool();
-	ui->meter->setChecked(value);
-	ui->feet->setChecked(!value);
+	unit = s.value("length").toInt();
+	ui->meter->setChecked(unit == units::METERS);
+	ui->feet->setChecked(unit == units::FEET);
 
-	value = s.value("units_bar").toBool();
-	ui->bar->setChecked(value);
-	ui->psi->setChecked(!value);
+	unit = s.value("pressure").toInt();
+	ui->bar->setChecked(unit == units::BAR);
+	ui->psi->setChecked(unit == units::PSI);
 
-	value = s.value("units_liter").toBool();
-	ui->liter->setChecked(value);
-	ui->cuft->setChecked(!value);
+	unit = s.value("volume").toInt();
+	ui->liter->setChecked(unit == units::LITER);
+	ui->cuft->setChecked(unit == units::CUFT);
 
-	value = s.value("units_kgs").toBool();
-	ui->kgs->setChecked(value);
-	ui->lbs->setChecked(!value);
+	unit = s.value("weight").toInt();
+	ui->kgs->setChecked(unit == units::KG);
+	ui->lbs->setChecked(unit == units::LBS);
+
+	s.endGroup();
 
 	// Defaults
+	s.beginGroup("GeneralSettings");
 	ui->font->setFont( QFont(s.value("table_fonts").toString()));
 	ui->fontsize->setValue(D(font_size));
 
 	ui->defaultfilename->setText(s.value("default_file").toString());
 	ui->displayinvalid->setChecked(B(show_invalid));
-
+	s.endGroup();
 #undef B
 #undef D
 }
@@ -95,11 +101,11 @@ void PreferencesDialog::syncSettings()
 	// Units
 	s.beginGroup("Units");
 	s.setValue("units_metric", ui->metric->isChecked());
-	s.setValue("fahrenheit", ui->fahrenheit->isChecked() ? units::FAHRENHEIT : units::CELSIUS);
-	s.setValue("feet", ui->feet->isChecked() ? units::FEET : units::METERS);
-	s.setValue("psi", ui->psi->isChecked() ? units::PSI : units::BAR);
-	s.setValue("cuft", ui->cuft->isChecked() ? units::CUFT : units::LITER);
-	s.setValue("lbs", ui->lbs->isChecked() ? units::LBS : units::KG);
+	s.setValue("temperature", ui->fahrenheit->isChecked() ? units::FAHRENHEIT : units::CELSIUS);
+	s.setValue("length", ui->feet->isChecked() ? units::FEET : units::METERS);
+	s.setValue("pressure", ui->psi->isChecked() ? units::PSI : units::BAR);
+	s.setValue("volume", ui->cuft->isChecked() ? units::CUFT : units::LITER);
+	s.setValue("weight", ui->lbs->isChecked() ? units::LBS : units::KG);
 	s.endGroup();
 	// Defaults
 	s.beginGroup("GeneralSettings");
diff --git a/qt-ui/profilegraphics.cpp b/qt-ui/profilegraphics.cpp
index deef8a9d5..722cea6bd 100644
--- a/qt-ui/profilegraphics.cpp
+++ b/qt-ui/profilegraphics.cpp
@@ -220,14 +220,19 @@ void ProfileGraphicsView::clear()
 	toolTip = 0;
 }
 
-void ProfileGraphicsView::plot(struct dive *d)
+void ProfileGraphicsView::refresh()
+{
+	plot(current_dive, TRUE);
+}
+
+void ProfileGraphicsView::plot(struct dive *d, bool forceRedraw)
 {
 	struct divecomputer *dc;
 
 	if (d)
 		dc = select_dc(&d->dc);
 
-	if (dive == d && (d && dc == diveDC))
+	if (!forceRedraw && dive == d && (d && dc == diveDC))
 		return;
 
 	clear();
diff --git a/qt-ui/profilegraphics.h b/qt-ui/profilegraphics.h
index 715c81ebf..963dd7d90 100644
--- a/qt-ui/profilegraphics.h
+++ b/qt-ui/profilegraphics.h
@@ -62,7 +62,7 @@ class ProfileGraphicsView : public QGraphicsView
 Q_OBJECT
 public:
 	ProfileGraphicsView(QWidget* parent = 0);
-	void plot(struct dive *d);
+	void plot(struct dive *d, bool forceRedraw = FALSE);
 	bool eventFilter(QObject* obj, QEvent* event);
 	void clear();
 
@@ -72,6 +72,9 @@ protected:
 	void wheelEvent(QWheelEvent* event);
 	void showEvent(QShowEvent* event);
 
+public Q_SLOTS:
+	void refresh();
+
 private:
 	void plot_depth_profile();
 	QGraphicsSimpleTextItem* plot_text(text_render_options_t *tro, const QPointF& pos, const QString &text, QGraphicsItem *parent = 0);