Rabbi Dovid Cohen
Administrative Rabbinic Coordinator
Updated May 2020
Nowadays, many appliances, especially ovens, are sold with a “Sabbath mode”, and the following is an attempt to clarify how that mode is helpful to consumers. The primary function of the Sabbath mode is to override the following features of modern ovens that conflict with the needs of a kosher home, including:
- Auto shutoff which shuts off the oven after 12 or 24 hours to conserve energy and/or prevent fires.
- Lights and signals that go on or off when one opens the door, food finishes cooking, the temperature is adjusted etc.
Once these features are overridden, the oven basically reverts to being an ‘old fashioned’ oven and the following halachos apply:
On Shabbos
- Fires cannot be turned on or off or adjusted up or down on the stovetop or in the oven.
- Food cannot be placed on the stovetop or in the oven on Shabbos, whether it is put there to cook or warm. Consumers should consult with their Rabbis regarding permitted ways to warm food on Shabbos or leave it on the fire from before Shabbos, as the details of the halachos of chazarah and shehiyah are quite intricate.
- The oven should be turned off before Shabbos, even if one has activated the “Sabbath mode” to override the concerns described above. Although Rav Moshe Feinstein was lenient in certain cases to open an oven door on Shabbos even when the oven is on, this is subject to debate and various other conditions, and therefore should be avoided unless done in careful consultation with one’s Rabbi.
On Yom Tov
- New fires cannot be turned on and existing fires cannot be turned off both on the stovetop or in the oven.
- A fire on the stovetop which is on, may be adjusted higher or lower to help cooking or prevent food from burning, but not for other reasons (e.g. to save fuel).
- The “Sabbath mode” setting on an oven enables one to leave the oven on during Yom Tov, and to open and close the over doors while the fire is on (if the fire is off, see below).
- There are differing opinions as to whether one may open the doors of an oven when the oven is on but the fire is off, and Rav Schwartz has ruled that it is permitted.
- If the fire is visibly burning in the oven, the thermostat may be adjusted higher, and if the fire is not burning then the thermostat may be adjusted lower. Both of these adjustments are only acceptable if the temperature is controlled by a non-electric dial (rather than with buttons).
- Cooking and warming of foods is permitted on Yom Tov.
- Some claim that since there’s a random delay between one’s adjusting the oven’s thermostat and the flame’s reaction, one may therefore adjust temperatures at will (on Yom Tov). However, this opinion is not widely accepted.
- If someone forgot to put their oven into Sabbath mode before Shabbos or Yom Tov, they should consult with their local Rabbi as to whether a non-Jew may do that for them.