diff --git a/homeassistant/components/climate/generic_thermostat.py b/homeassistant/components/climate/generic_thermostat.py
index 1b3d20d8b59..a40795c37c5 100644
--- a/homeassistant/components/climate/generic_thermostat.py
+++ b/homeassistant/components/climate/generic_thermostat.py
@@ -198,24 +198,30 @@ class GenericThermostat(ClimateDevice):
                 return
 
         if self.ac_mode:
-            too_hot = self._cur_temp - self._target_temp > self._tolerance
             is_cooling = self._is_device_active
-            if too_hot and not is_cooling:
-                _LOGGER.info('Turning on AC %s', self.heater_entity_id)
-                switch.turn_on(self.hass, self.heater_entity_id)
-            elif not too_hot and is_cooling:
-                _LOGGER.info('Turning off AC %s', self.heater_entity_id)
-                switch.turn_off(self.hass, self.heater_entity_id)
+            if is_cooling:
+                too_cold = self._target_temp - self._cur_temp > self._tolerance
+                if too_cold:
+                    _LOGGER.info('Turning off AC %s', self.heater_entity_id)
+                    switch.turn_off(self.hass, self.heater_entity_id)
+            else:
+                too_hot = self._cur_temp - self._target_temp > self._tolerance
+                if too_hot:
+                    _LOGGER.info('Turning on AC %s', self.heater_entity_id)
+                    switch.turn_on(self.hass, self.heater_entity_id)
         else:
-            too_cold = self._target_temp - self._cur_temp > self._tolerance
             is_heating = self._is_device_active
-
-            if too_cold and not is_heating:
-                _LOGGER.info('Turning on heater %s', self.heater_entity_id)
-                switch.turn_on(self.hass, self.heater_entity_id)
-            elif not too_cold and is_heating:
-                _LOGGER.info('Turning off heater %s', self.heater_entity_id)
-                switch.turn_off(self.hass, self.heater_entity_id)
+            if is_heating:
+                too_hot = self._cur_temp - self._target_temp > self._tolerance
+                if too_hot:
+                    _LOGGER.info('Turning off heater %s',
+                                 self.heater_entity_id)
+                    switch.turn_off(self.hass, self.heater_entity_id)
+            else:
+                too_cold = self._target_temp - self._cur_temp > self._tolerance
+                if too_cold:
+                    _LOGGER.info('Turning on heater %s', self.heater_entity_id)
+                    switch.turn_on(self.hass, self.heater_entity_id)
 
     @property
     def _is_device_active(self):
diff --git a/tests/components/climate/test_generic_thermostat.py b/tests/components/climate/test_generic_thermostat.py
index 1730c3e003b..7c4ee8db58f 100644
--- a/tests/components/climate/test_generic_thermostat.py
+++ b/tests/components/climate/test_generic_thermostat.py
@@ -181,34 +181,10 @@ class TestClimateGenericThermostat(unittest.TestCase):
         self.assertEqual(SERVICE_TURN_OFF, call.service)
         self.assertEqual(ENT_SWITCH, call.data['entity_id'])
 
-    def test_set_temp_change_heater_on(self):
-        """Test if temperature change turn heater on."""
-        self._setup_switch(False)
-        climate.set_temperature(self.hass, 30)
-        self.hass.block_till_done()
-        self._setup_sensor(25)
-        self.hass.block_till_done()
-        self.assertEqual(1, len(self.calls))
-        call = self.calls[0]
-        self.assertEqual('switch', call.domain)
-        self.assertEqual(SERVICE_TURN_ON, call.service)
-        self.assertEqual(ENT_SWITCH, call.data['entity_id'])
-
-    def test_temp_change_heater_off(self):
-        """Test if temperature change turn heater off."""
-        self._setup_switch(True)
-        climate.set_temperature(self.hass, 25)
-        self.hass.block_till_done()
-        self._setup_sensor(30)
-        self.hass.block_till_done()
-        self.assertEqual(1, len(self.calls))
-        call = self.calls[0]
-        self.assertEqual('switch', call.domain)
-        self.assertEqual(SERVICE_TURN_OFF, call.service)
-        self.assertEqual(ENT_SWITCH, call.data['entity_id'])
-
     def test_temp_change_heater_on_within_tolerance(self):
-        """Test if temperature change turn heater on within tolerance."""
+        """Test if temperature change doesn't turn heater on within
+        tolerance.
+        """
         self._setup_switch(False)
         climate.set_temperature(self.hass, 30)
         self.hass.block_till_done()
@@ -217,9 +193,7 @@ class TestClimateGenericThermostat(unittest.TestCase):
         self.assertEqual(0, len(self.calls))
 
     def test_temp_change_heater_on_outside_tolerance(self):
-        """Test if temperature change doesn't turn heater on outside
-        tolerance.
-        """
+        """Test if temperature change turn heater on outside tolerance."""
         self._setup_switch(False)
         climate.set_temperature(self.hass, 30)
         self.hass.block_till_done()
@@ -231,6 +205,30 @@ class TestClimateGenericThermostat(unittest.TestCase):
         self.assertEqual(SERVICE_TURN_ON, call.service)
         self.assertEqual(ENT_SWITCH, call.data['entity_id'])
 
+    def test_temp_change_heater_off_within_tolerance(self):
+        """Test if temperature change doesn't turn heater off within
+        tolerance.
+        """
+        self._setup_switch(True)
+        climate.set_temperature(self.hass, 30)
+        self.hass.block_till_done()
+        self._setup_sensor(31)
+        self.hass.block_till_done()
+        self.assertEqual(0, len(self.calls))
+
+    def test_temp_change_heater_off_outside_tolerance(self):
+        """Test if temperature change turn heater off outside tolerance."""
+        self._setup_switch(True)
+        climate.set_temperature(self.hass, 30)
+        self.hass.block_till_done()
+        self._setup_sensor(35)
+        self.hass.block_till_done()
+        self.assertEqual(1, len(self.calls))
+        call = self.calls[0]
+        self.assertEqual('switch', call.domain)
+        self.assertEqual(SERVICE_TURN_OFF, call.service)
+        self.assertEqual(ENT_SWITCH, call.data['entity_id'])
+
     def _setup_sensor(self, temp, unit=TEMP_CELSIUS):
         """Setup the test sensor."""
         self.hass.states.set(ENT_SENSOR, temp, {
@@ -297,7 +295,18 @@ class TestClimateGenericThermostatACMode(unittest.TestCase):
         self.assertEqual(SERVICE_TURN_ON, call.service)
         self.assertEqual(ENT_SWITCH, call.data['entity_id'])
 
-    def test_set_temp_change_ac_off(self):
+    def test_temp_change_ac_off_within_tolerance(self):
+        """Test if temperature change doesn't turn ac off within
+        tolerance.
+        """
+        self._setup_switch(True)
+        climate.set_temperature(self.hass, 30)
+        self.hass.block_till_done()
+        self._setup_sensor(29.8)
+        self.hass.block_till_done()
+        self.assertEqual(0, len(self.calls))
+
+    def test_set_temp_change_ac_off_outside_tolerance(self):
         """Test if temperature change turn ac off."""
         self._setup_switch(True)
         climate.set_temperature(self.hass, 30)
@@ -310,7 +319,18 @@ class TestClimateGenericThermostatACMode(unittest.TestCase):
         self.assertEqual(SERVICE_TURN_OFF, call.service)
         self.assertEqual(ENT_SWITCH, call.data['entity_id'])
 
-    def test_temp_change_ac_on(self):
+    def test_temp_change_ac_on_within_tolerance(self):
+        """Test if temperature change doesn't turn ac on within
+        tolerance.
+        """
+        self._setup_switch(False)
+        climate.set_temperature(self.hass, 25)
+        self.hass.block_till_done()
+        self._setup_sensor(25.2)
+        self.hass.block_till_done()
+        self.assertEqual(0, len(self.calls))
+
+    def test_temp_change_ac_on_outside_tolerance(self):
         """Test if temperature change turn ac on."""
         self._setup_switch(False)
         climate.set_temperature(self.hass, 25)