diff --git a/soft/thermostat/inc/mainwindow.h b/soft/thermostat/inc/mainwindow.h
index e524007..461115a 100644
--- a/soft/thermostat/inc/mainwindow.h
+++ b/soft/thermostat/inc/mainwindow.h
@@ -19,6 +19,13 @@
 #include "backgroundloop.h"
 #include "settings.h"
 
+enum power_states {
+	OFF,
+	ON,
+	AUTO,
+	MAX_POWER_STATES
+};
+
 class MainWindow : public QMainWindow
 {
 	Q_OBJECT
@@ -28,15 +35,19 @@ public:
 	~MainWindow();
 
 	MQTTSubcriber *mqttclient;
-private:
 
+private:
+	QPushButton m_state_btn;
 	BackgroundLoop m_backLoop;
 	QVector<ZoneItem *> m_zones;
+	enum power_states m_pwr_state;
+	void update_state_btn(enum power_states st);
 
 private slots:
 	void temperature_slot(int idx, double val);
 	void hygro_slot(int idx, double val);
 	void availability_slot(int idx, bool ok);
+	void change_state(void);
 };
 
 #endif // MAINWINDOW_H
diff --git a/soft/thermostat/src/mainwindow.cpp b/soft/thermostat/src/mainwindow.cpp
index d314d55..a9a88dd 100644
--- a/soft/thermostat/src/mainwindow.cpp
+++ b/soft/thermostat/src/mainwindow.cpp
@@ -43,6 +43,8 @@ MainWindow::MainWindow(QWidget *parent) :
 	 */
 	QGridLayout *mainLayout = new QGridLayout;
 
+	m_state_btn.setText(tr("Auto"));
+
 	if (s->nbZones() < 4) {
 		// TODO
 		qDebug() << "bad configuration" ;
@@ -52,11 +54,13 @@ MainWindow::MainWindow(QWidget *parent) :
 		mainLayout->addWidget(new QPushButton(tr("Menu")), 0, 2);
 		mainLayout->addWidget(m_zones.at(2), 1, 0);
 		mainLayout->addWidget(m_zones.at(3), 1, 1);
-		mainLayout->addWidget(new QPushButton(tr("Auto")), 1, 2);
+		mainLayout->addWidget(&m_state_btn, 1, 2);
 	}
+	m_pwr_state = OFF;
+	update_state_btn(m_pwr_state);
+
 	QWidget *mainWidget = new QWidget;
 	mainWidget->setLayout(mainLayout);
-
 	/*
 	 * Top widget
 	 */
@@ -66,12 +70,50 @@ MainWindow::MainWindow(QWidget *parent) :
 	m_backLoop.start();
 
 	mqttclient->connectToHost();
+
+	connect(&m_state_btn, SIGNAL(clicked()), this, SLOT(change_state()));
 }
 
 MainWindow::~MainWindow()
 {
 }
 
+void MainWindow::update_state_btn(enum power_states st)
+{
+	switch (st) {
+	case OFF:
+		m_state_btn.setText(tr("Force off"));
+		break;
+	case ON:
+		m_state_btn.setText(tr("Force on"));
+		break;
+	case AUTO:
+		m_state_btn.setText(tr("Auto"));
+		break;
+	default:
+		m_state_btn.setText(tr("Error"));
+		break;
+	}
+}
+
+void MainWindow::change_state(void)
+{
+	switch (m_pwr_state) {
+	case OFF:
+		m_pwr_state = ON;
+		break;
+	case ON:
+		m_pwr_state = AUTO;
+		break;
+	case AUTO:
+		/* fall through */
+	default:
+		m_pwr_state = OFF;
+		break;
+	}
+	update_state_btn(m_pwr_state);
+}
+
 void MainWindow::temperature_slot(int idx, double val)
 {
 	Settings *s = Settings::getInstance();