Is it Permitted to Move a Fan on Shabbat?
A practical guide to handling electric appliances on the holy day

Answer: In order to address this question, we need to examine which type of muktzeh (prohibited object to move on Shabbat) might forbid moving a fan or electric blanket on Shabbat.
From the perspective of "muktzeh machmat gufo" (inherently prohibited objects), there is certainly no prohibition, since muktzeh machmat gufo refers to items that are not "vessels" and are not designated for any use on Shabbat. However, fans and blankets are considered "vessels" and are definitely made to be used on Shabbat.
But we must consider the category of "kli shemelachto l'issur" (a vessel whose primary purpose involves a prohibited activity). Our Sages prohibited the moving of vessels that are designated for work that is forbidden on Shabbat, such as a hoe, rake, chisel, or hammer. Since these are made for work prohibited on Shabbat, it is forbidden to move them. It is known that it is prohibited to turn on a fan on Shabbat, and likewise prohibited to turn on an electric blanket on Shabbat. According to this, it would seem that it should be forbidden to move them on Shabbat.The Tosafot (in Tractate Shabbat 36a) wrote that a lamp made for lighting is considered a vessel whose primary purpose is prohibited, as it is forbidden to light it on Shabbat. However, Rabbi Akiva Eiger cited that the Rashba and other early authorities wrote that a lamp is not considered a vessel whose primary purpose is prohibited, because such a vessel is one that inherently serves a prohibited purpose through its movement, like a hammer or chisel. But an item whose operation involves prohibition, yet the item itself does not serve for prohibition, is not considered muktzeh due to being a vessel whose primary purpose is prohibited (rather, it might be prohibited as a base for a prohibited item).
From this, it appears that an electric blanket and a fan are not considered muktzeh on Shabbat since they are not vessels whose primary purpose is prohibited; they are merely operated by means prohibited on Shabbat. This was also ruled by Rabbi Shlomo Zalman Auerbach and Rabbi Moshe Feinstein, that an item operated by electricity is not necessarily considered muktzeh unless it is made for prohibited work, such as a drill or similar items. Therefore, it is permitted on Shabbat to move a fan to direct it in another direction, and it is also permitted to move an electric blanket on Shabbat.
For this reason, and for several other reasons, our great rabbi (may he live a good and long life) wrote that it is permissible for a hearing-impaired person to move the hearing aid in his ear on Shabbat, since this device is not muktzeh, even though it operates by electrical power.
In summary: It is permitted to adjust a fan to a different direction on Shabbat, and it is also permitted to use an electric blanket on Shabbat that was connected to the electrical current before Shabbat. However, one should be careful not to disconnect the power cord from the wall socket.
Rulings of Rabbi Ovadia Yosef shlita courtesy of "Daily Halacha" website
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