diff --git a/homeassistant/components/climate/daikin.py b/homeassistant/components/climate/daikin.py
index 1f38fdf3c82..fea1fcee3a3 100644
--- a/homeassistant/components/climate/daikin.py
+++ b/homeassistant/components/climate/daikin.py
@@ -98,10 +98,16 @@ class DaikinClimate(ClimateDevice):
         daikin_attr = HA_ATTR_TO_DAIKIN[ATTR_FAN_MODE]
         if self._api.device.values.get(daikin_attr) is not None:
             self._supported_features |= SUPPORT_FAN_MODE
+        else:
+            # even devices without support must have a default valid value
+            self._api.device.values[daikin_attr] = 'A'
 
         daikin_attr = HA_ATTR_TO_DAIKIN[ATTR_SWING_MODE]
         if self._api.device.values.get(daikin_attr) is not None:
             self._supported_features |= SUPPORT_SWING_MODE
+        else:
+            # even devices without support must have a default valid value
+            self._api.device.values[daikin_attr] = '0'
 
     def get(self, key):
         """Retrieve device settings from API library cache."""