5786/2026
Hatmanah
We conclude our discussion of Bishul with a brief look at the rabbinic prohibition of Hatmanah. Chazal forbade us from enveloping a pot of food on Shabbat to maintain its heat lest one stir the coals (or adjust the flame). In addition, Chazal forbade us from enveloping a pot of food even on Erev Shabbat if the material used to envelop the pot warms the food. See Shulchan Aruch Orach Chaim 257 and Halachapedia’s Hatmanah entry for a full presentation of these laws.
Crockpots
Concern for Hatmanah arises occasionally, especially regarding crock pots.
Until 1995, many people used a two-piece crockpot to cook Chulent for Shabbat. In 1995, some changed their practice when Rav Shlomo Zalman Auerbach (Teshuvot Minchat Shlomo 2:34:5) ruled that using a two-piece crockpot violates the rabbinical prohibition of Hatmanah. Since the outer pot contains the electric coils that heat the inner pot, Rav Shlomo Zalman asserts that one is Matmin (enveloping) the inner pot with the outer pot, which warms the food in the inner pot.
Nevertheless, some people still use a two-piece crockpot to prepare Chulent for Shabbat. Their Halachic basis is that the outer pot does not completely envelop the inner pot, as the former does not cover the latter on its top. The Rama (O.C. 253:1) rules that one violates Hatmana only when the material completely envelops the pot, including its top. The cover of the pot is not considered to be “enveloping” the pot, since its function is to cover the pot, not to warm the food. Rav Moshe Feinstein (Teshuvot Igrot Moshe O.C. 1:95) presents a similar line of reasoning in his ruling that storing hot liquids in a thermos does not constitute Hatmanah.
However, others argue (based on Rabbeinu Tam’s Sefer HaYashar 235) that the Rama does not require complete envelopment, as even if a majority of the pot is wrapped in insulating material, it is Hatmana. Rav Schachter (The Laws of Cooking and Warming Food on Shabbat, p. 184) and Rav Willig (The Laws of Cooking and Warming Food on Shabbat, pp. 126-127) follow Rav Shlomo Zalman.
Sefardim
Rav Ovadia Yosef (Chazon Ovadia Shabbat 1:64-65) writes that three factors combine to permit Sephardic Jews to use a two-piece crockpot on Shabbat. First, considering the Rama, it is not covered with a heating element on top. Second, the opinions (cited in the Rama to Orach Chaim 257:1) that say that Hatmanah applies only to food prepared for Friday night (we are not concerned that he will stir the coals for food that is only to be eaten during the Shabbat afternoon meal). Third, there is a small space between the heating element and the pot that contains the food (Hatmanah applies only when the insulating material directly touches the food or its pot; see Shulchan Aruch, Orach Chaim 257:8).
Solutions According to Rav Shlomo Zalman
Rav Yosef Shalom Elyashiv (cited in Orchot Shabbat p. 540) rules that one can avoid the issue by placing something under the pot (such as marbles) to lift it slightly off the floor of the element. In this way, the base does not surround the bottom of the pot; the top will be exposed, and the top part of it will not be considered enclosed. In this manner, the majority of the crockpot is enveloped in insulating material.
Rav Dovid Ribiat (The 39 Melochos, p. 615) advises lining the inside wall of the crockpot with aluminum foil and having the foil extend noticeably above its rim. The foil also serves as a barrier between the heating element and the pot holding the food, alleviating concerns for Hatmana.
Many follow one of these two approaches.
Shehiyah
Rav Shlomo Zalman also expresses concern for Shehiyah. Rav Ovadia Yosef writes that this concern can be overcome by covering the crockpot’s knobs. Rav Willig told me that he ensures the food in his crockpot is cooked to Ma’achal Ben Derosai before Shabbat, following Chananiah. One may also place the food in a crockpot immediately before Shabbat, following the Kedeirah Chaitah option. Arguably, the aluminum foil lining makes the crockpot equivalent to Katumah, as it reduces the fire’s intensity.
Malca Jachter’s Crockpot
My wife, Malca, uses a crockpot from a mainstream manufacturer that produces a model designed to satisfy Shabbat observers, which appears to address all Shabbat concerns. First, the crockpot sits atop a flat heating element to avoid the Hatmanah concern, which applies only when the top rests inside a circular heating element. Second, the knob is covered by a plastic cover. Third, there is an aluminum metal sheet that protrudes upward slightly to serve as a Blech between the heating element and the cooking pot. The knob cover and aluminum metal sheet (upon which it is written “For Shabbos Use Only”) overcome concern for Sheiya and seem to satisfy the Garuf V’Katum requirement for Hachazra. Finally, Malca uses the top piece for Kedeirah Al Gabei Kedeirah placing. Since the top piece rests on a Blech, it satisfies Rav Willig’s preference for a Kedeirah Al Gabei Kedeirah to be used only on a covered fire (The Laws of Cooking and Warming Food on Shabbat, p. 111).
This product has so many Halachic advantages that Malca even purchased similar crockpots for our children, Bracha, Binyamin, and Atara, when they married.
Conclusion
Rav Shlomo Zalman Auerbach’s crockpot ruling resonated in many circles, especially since this was reportedly the last ruling Rav Shlomo Zalman rendered before his passing. It is even recounted that the crockpots of many leading rabbis suddenly became inoperable on the Shabbat after Rav Shlomo Zalman issued this ruling!
Nonetheless, miracles do not determine Halachah (Bava Metzia 59b; “Lo BaShamayim Hee”), and the debate regarding the use of a crockpot on Shabbat remains, with some adhering to the stricter guidelines and others being lenient.