Question: May one use an electric blanket (heating pad) on Shabbat or is it prohibited to be moved due to the prohibition of Muktzeh? Similarly, may one turn a fan to another direction on Shabbat?
Answer: In the previous Halachot we have discussed several laws of Muktzeh on Shabbat which are objects our Sages have prohibited moving on Shabbat. When addressing the above question, we must first clarify what category of Muktzeh moving an electric blanket or fan falls into.
Certainly, these objects cannot be classified as “innate Muktzeh,” for only objects which are not a “vessel” and do not serve any purpose on Shabbat fall into this category. A blanket and a fan, however, are considered “vessels” and they most definitely do serve a purpose on Shabbat.
We must consider though the law of “a tool which is used for work forbidden on Shabbat”. Our Sages prohibited moving tools that are designated for work forbidden on Shabbat, such as a rake, shovel, or hammer. Clearly, it is forbidden to turn on a fan or an electric blanket on Shabbat. It would seem then that it should be prohibited to move these objects on Shabbat.
The Tosafot (Shabbat 36a) write that a candle which is made to be lit is considered “a tool used for work forbidden on Shabbat.” Nevertheless, Hagaon Rabbeinu Akiva Eiger quotes the Rashba and other great Rishonim who write that a candle is not a “tool used for work forbidden on Shabbat,” for this only applies to tools which are used themselves for the forbidden work through being moved, such as a hammer or a shovel; however, an object whose igniting is forbidden but is not used itself to perform the forbidden work cannot be classified as a “tool used for work forbidden on Shabbat”. (A candle may, nevertheless, not be moved on Shabbat because of a different law called, “A base for a forbidden object”, which we shall, G-d willing, explain another time).
It would now seem that an electric blanket or fan should not be considered Muktzeh on Shabbat since they are, in essence, not “tools used for work forbidden on Shabbat”; rather they are only powered on by an action prohibited on Shabbat. Similarly, Hagaon Harav Shlomo Zalman Auerbach and Hagaon Harav Moshe Feinstein rule that an object which is turned on through electricity is not necessarily considered Muktzeh on Shabbat unless it is used to perform a work forbidden on Shabbat, such as a drill and the like. Therefore, one may move a fan on Shabbat in order to turn it to a different direction. Similarly, one may move an electric blanket on Shabbat.
For this reason, among other considerations, Maran zt”l writes that one who is hard of hearing may move his hearing aid on Shabbat since this device is not Muktzeh although it is powered by electricity (or battery power).
Summary: One may turn a fan to another direction on Shabbat. Similarly, one may use an electric blanket on Shabbat that was connected to a power source before the onset of Shabbat. However, care must be taken that the plug not be pulled out of the outlet on Shabbat.