I have two identical ceiling fans in my house that were installed around 4 years ago. One no longer rotates as fast as it used to at top speed. At a guess I would say it has lost 30 or 40% of its speed.
All other electrical items in the room and house seem fine and the fan is not making any unusual noises, nor does it seem to be restrained or struggling to spin.
Could anyone suggest what could be causing this?