The Use Of Timers On Shabbat and Setting A Washing Machine Right Before Shabbat Starts
Taken from Daily Halacha by: Rabbi Eli Mansour
The Gemara in Masechet Shabbat Daf 18 brings down a Halacha that is used as the basis for some very important Halachot in today’s technological culture. The Gemara there brings a case where right before Shabbat some wheat was placed in a grinder that was being powered by a water wheel. The water wheel spurred into Shabbat grinding and processing the wheat. This was permissible on Shabbat according to Bet Hillel, because everything was set in motion from before Shabbat, and no action was actually being performed on Shabbat itself. Maran reiterates this Halacha in Shulchan Aruch in siman 252:6. The Halacha, it is permissible to put wheat in the water wheel powered grinder from before Shabbat even though it would continue grinding into Shabbat, and even though it would make noise on Shabbat. This is permissible because no forbidden action was being performed on Shabbat itself.
Additionally, a radio may not be programmed to go on or off on Shabbat. It might be permissible to listen to a news station during the week, but it is forbidden to program a timer to turn on a radio tuned in to a news station or any other station on Shabbat. Many people use alarm clocks on Shabbat that play the radio. This is forbidden. While it is permissible to have an alarm clock chime at a preset time on Shabbat, it is however forbidden to have the alarm clock play the news or any music on Shabbat. It is a Zilzul (degradation) of the Shabbat to have the news on, for the radio stations will broadcast business issues, advertisements, and other inappropriate for Shabbat content.
Further, I want to bestow on everyone as the summer months approach, that one may not at all program a timer to activate a stereo or music player on Shabbat. This was not the intent of the Chachamim when they allowed the use of timers. We unfortunately see people program timers to play music over a speaker system on Shabbat. This is 100% forbidden on Shabbat. This would be disgraceful and a Chilul Hashem.
So based on the Gemara in Masechet Shabbat, Daf 18, the Chachamim enabled us to program timers to activate and deactivate lights, air conditioning, and heating on Shabbat. One should not abuse this privilege and program timers to turn on and off televisions, radios, or stereo players. Additionally based on this Gemara, for Sephardim it would be permissible to put on a washing machine, dryer, or dishwasher right before Shabbat even though the machine would make noise and operate during Shabbat. This would be permitted because although the machine would be working, there would be however no action performed by the individual during the Shabbat itself.