Check import

homeassistant/components/thermostat/radiotherm.py

@@ -21,7 +21,13 @@ _LOGGER = logging.getLogger(__name__)
 
 def setup_platform(hass, config, add_devices, discovery_info=None):
     """ Sets up the Radio Thermostat. """
-    import radiotherm
+    try:
+        import radiotherm
+    except ImportError:
+        _LOGGER.exception(
+            "Unable to import radiotherm. "
+            "Did you maybe not install the 'radiotherm' package?")
+        return False
 
     hosts = []
     if CONF_HOST in config: