Heating capacity for appropriate size

The heat output corresponds felt the specified 500 W. In order to heat the air in a medium sized room, this fan is therefore not suitable. Nevertheless, there are of course for such a product matching applications.
On my machine it came to a total of several hours duration to a permanent, loud hum and vibrate, so that the fan on smooth underground space automatically rotated (assumption: bearing damage). So the fan was practically no longer usable.