5. Scenarios in which insulating on Shabbos is permitted:

A. Placing an upside-down pot over a hot pot on Shabbos:[1]

It is forbidden to place a vessel as a covering over a hot pot for the purpose of retaining its heat (if the pot is entirely insulated underneath the vessel[2]), unless the vessel is wide enough to the point that its walls do not touch the sides of the pot[3], in which case there is no [prohibition of] insulation being done at all.

 

B. Covering the pot in order to guard it:[4]

It is permitted to place a vessel on top of food in order to guard it from mice, or so that it not get dirty from the ash, as this is not considered insulating for retaining of heat, but rather is a measure of guarding and [is like] placing a cover on top of a pot.

May one cover the pot even with materials that add heat when his intent is to guard it? Yes.[5] However some Poskim[6] are stringent in this matter. May one cover the pots in order to prevent his children from touching it and receiving a burn?[7] Yes.

C. May one re-insulate on Shabbos a pot that had been insulated before Shabbos?[8]

If one insulated [a pot] from before Shabbos with a material that does not add heat, and it unraveled before Shabbos, whether it unraveled on its own, or if one unraveled it with his hands and one had in mind to go back and re-insulate it before Shabbos or after Shabbos has begun, then it is forbidden to re-insulate it once Shabbos has begun [past Bein Hashmashos], as this is considered like one is initially insulating [the pot] on Shabbos [which is forbidden to do], since when Shabbos came in it was not insulated.

However, if it was insulated[9] in the beginning of the entrance of (Shabbos[10]) the night, and then afterwards it unraveled, it is permitted to re-insulate it. This applies whether it unraveled on its own or if one did so with his hands, even if [at the time that he unraveled it] he did not have in mind to go back and insulate it[11]. [Furthermore] even initially one may unravel it and then return and insulate it. [See Q&A 1]

May one add insulating material to an already fully insulated pot? If one wants to add [to the insulating material] on Shabbos other materials which do not add heat, he may do so. As well if one wants to remove all of the insulating material [placed before Shabbos] and place other material there in its place, whether the original insulation is hotter than the second one, or if the second insulation is hotter than the first. Even if the pot was only insulated with a sheet, one can remove the sheet and insulate it with a thick blanket.

If the food is not fully cooked: [However] this only applies if the food was fully cooked, however if it is not fully cooked and is insulated on top of a Kirah (that has had its coals swept[12]), then it is forbidden to even add on to the cover, as this addition causes to speed up the cooking due to the coals. [See Q&A 2]

Q&A If the insulation was removed or unraveled by Bein Hashmahos may it be reinsulated after dark?[13] No.[14] The insulation must be intact when the night of Shabbos enters. This applies even if the congregation already accepted Shabbos, and afterwards the insulation unraveled before night, that it may not be reinsulated.[15]   If one insulated the food for purposes of protection may he then remove the insulation on Shabbos and replace it for purposes of insulation? This matter requires further clarification.[16]   If only part of the pot was insulated before Shabbos may one add insulation to it on Shabbos? No. One may not add insulation to make it fully insulated.[17]   May one return the insulating material even if he removed it with intent to not return it on Shabbos?[18] Yes.   Must one fulfill the Chazarah conditions in order to be allowed to return the insulation to the pot? No. One is not required to fulfill the Chazara conditions when returning the insulation to the pot.[19] However some Poskim are stringent regarding the opposite case, that one removed the pot from the insulation and now desires to return the pot to the insulation, as will be explained in the next Q&A!   May one reinsulate a pot that was insulated before Shabbos even if he removed the pot from the insulation, or only if he removed the insulation from the pot, leaving the pot in its original area?[20] There are Poskim[21] which say that when the pot was removed from the insulation one must fulfill all the conditions of Chazara to be allowed to return it to the insulation. However, this does not seem to be the opinion of the Alter Rebbe or the Mishneh Berurah.   May one re-insulate a pot or add insulation to a pot that was insulated before Shabbos even if the food is not fully cooked?[22] If the pot is standing over a source of heat then it may only be reinsulated if the food is fully cooked, as by returning the insulation one speeds up the cooking. However if the pot is not on any source of heat, then it is always allowed to re-insulate or add more insulation on Shabbos, even if the food is not fully cooked, as this does not make it cook any further.[23] [See footnote for opinion of M”B] May one add other pots that were not insulated before Shabbos into the insulation of an insulated pot? No.[24] May one add food to an insulated pot and then return the insulation?[25] If the insulated pot is a Keli Rishon, based on the previous Q&A, it is forbidden to do so.

D. Insulating on Shabbos food which has been transferred to a different pot:[26]

It was only made forbidden to insulate on Shabbos with material that does not add heat, when one is insulating the actual pot in which the food was cooked in, as then the decree that one may come to heat it up is applicable. However, if one removed the food into another pot, it is permitted to insulate it. [See Q&A 1]

[Furthermore] even if one goes back and returns the food into the original pot, it is permitted to insulate it[27] (being that the food has already cooled off a little in the walls of the second pot, and the Sages only forbade insulating if the food is [still] hot in the original pot that it was cooked in.) [See Q&A]

The above is allowed only with materials that do not add heat: However, the above is only [allowed] when using insulation material that does not add heat, however material which adds heat, is forbidden to insulate with, even completely cold food, and even before Shabbos.

Q&A Does this permission apply even if the food is a solid substance [“Davar Gush”]?[28] Yes. This applies even according to those Poskim that are normally stringent regarding a Davar Gush in other Shabbos laws. [29] May one place hot water on Shabbos into an insulation thermos?[30] Yes, as the insulation is not being done to the original pot.[31] May one place hot water in a stomach pad? Yes. May one insulate a food that was placed from one Keli Rishon to another empty Keli Rishon?[32] No.[33] However, there are Poskim[34] that are lenient in this matter. Likewise, there are Poskim[35] that are lenient to allow pouring water into a thermos that was on a Keli Rishon.[36]  May one insulate a bottle of food that was entered into a Keli Rishon and became hot?[37] No.

• May one use a thermos on Shabbos?

Using a thermos on Shabbos involves pouring hot water into the thermos for the purpose of insulating its heat for an extended period of time, and hence touches upon the question of insulation. The following is the ruling:

It is Rabbinically forbidden to insulate hot foods or liquids on Shabbos even if the insulation does not add heat to the food, but simply conserves it.[38] This however only applies so long as the hot food or liquid remains in the original vessel that it was cooked in [i.e. Keli Rishon]. If, however, the food or liquid is poured into a second vessel, then there is no prohibition against insulating the second vessel on Shabbos.[39] Accordingly, there is no prohibition against using a thermos on Shabbos, and pouring boiling water into it for the sake of conserving the heat of the liquid.[40] For the same reason, it is likewise permitted to enter hot water into a stomach pad on Shabbos.[41]

E. Insulating cold food on Shabbos:[42]

([Furthermore] if the food cooled off to the point that it is not Yad Soledes, it is permitted to insulate it even while it is still in the original pot.[43]) and certainly it is permitted to insulate completely cold food in order so it not become too cold, or in order to remove its coldness [see note][44]. [See Q&A 1]
The above is allowed only with materials that do not add heat: However, all the above is only [allowed] when using insulation material that does not add heat, however material which adds heat is forbidden to insulate with. This applies even with completely cold food, and even before Shabbos.

May one on Shabbos place a cold bottle into a hot pot of water that is off the fire?[45] If the food will not be able to get heated to the point of Yad Soledes[46], or will but does not contain a cooking prohibition [such as the food is fully cooked and does not contain liquid, or the water is a Keli Sheiyni and the bottle contains only liquid], then if it is not completely submerged within the water, such as if the bottle is floating and the upper part of the bottle is revealed, then it is allowed.[47] However if it is completely submerged within the water, then it is only allowed if heat will not be added to the food, and rather is being placed there only to retain its current heat.[48] This applies even by a Keli Sheyni.[49]

_________________________________________________

[1] Admur 257:4

^[2] Meaning that the vessel completely covers the pot, both on its top and its sides, as is the case when one places a large pot over a smaller pot that the smaller pot fits entirely into the large pot.

^[3] Meaning there is space between the walls of the smaller pot and the walls of the large pot which is sitting over it; Based on the ruling of the Mahadura Basra 259 it is also necessary that the top of the pot does not touch the top of the lower pot. [Ketzos Hashulchan 71 footnote 38]

[4] Admur 257:4; Michaber 257:2; See Piskeiy Teshuvos 257:3 and 6

[5] Az Nidbaru 5:15; Rav SZ”A in Maor Hashabbos 1:11; Piskeiy Teshuvos 257:7; However see Minchas Shlomo 2:34-20

[6] Toras Shabbos 257:9

[7] Piskeiy Teshuvos 257 footnote 45

[8] Admur 257:8; Michaber 257:4; See Piskeiy Teshuvos 257:7-8; 259:1

^[9] Based on the definition of insulation for material that does not add heat. A pot is only considered to have been insulated from before Shabbos if its cover was insulated, whether or not its sides were insulated.

^[10] The question here is regarding Bein Hashmashos. Meaning if the insulation unraveled by Bein Hashmashos what law do we give it. Seemingly this is the novelty in the additional words “Shabbos” that the Alter Rebbe is saying that once Shabbos has begun, which is after sunset, if it was insulated and unraveled one may reinsulate it on Shabbos. The Piskeiy Teshuvos 257 footnote 51 interprets the added word Shabbos in parentheses to include if the congregation accepted Shabbos upon themselves and does not include Bein Hashmashos. See Q&A for the final ruling on this matter! 

^[11] Seemingly this includes even if one specifically had in mind to not reinsulate it, and then changed his mind, that he is allowed to do it. So rules the Aruch Hashulchan 257:20; and is implied from the Tehila Lidavid. [Shabbos Kehalacha vol. 2 page 63-64]

[12] See M”A 257

[13] See Piskeiy Teshuvos 257:7; Shabbos Kehalacha 11 footnote 83 [p. 62]

[14] Shaar Hatziyon 257:25 in name of Gr”a; wording of Michaber is “at dark”; Damesek Eliezer on Gr”a; Shabbos Kehalacha ibid; Piskeiy Teshuvos ibid

Ruling of Admur: Admur ibid writes “However if it was insulated in the beginning of the entrance of (Shabbos) the night”. Seemingly the novelty in the additional words “Shabbos” is that the Alter Rebbe is saying that once Shabbos has begun, which is after sunset, if it was insulated and unraveled, one may reinsulate it on Shabbos. However, since these words were placed in parentheses, Tzaruch Iyun as to how we should rule. Practically in Shabbos Kehalacha ibid, after bringing the sides for the issue, concludes that one should be stringent. The Piskeiy Teshuvos 257 footnote 51 interprets the added word Shabbos in parentheses to include if the congregation accepted Shabbos upon themselves and does not include Bein Hashmashos. The reason for this is because it is permitted toi insulate during Bein Hashmashos, and this it is not yet considered as if it was insulated into Shabbos. However, it is forbidden to insulate once Maariv was prayed and hence it is considered the pot was insulated into Shabbos.

[15] See Piskeiy Teshuvos ibid that writes “it’s possible in such a case that it is permitted to do so”; However, Shabbos Kehalacha ibid concludes not to do so.

[16] Piskeiy Tehsuvos 257 footnote 52 writes it is forbidden. However, Tzaruch Iyun as perhaps the reason for allowing the reinsulation is because the pot will certainly still be warm if it contained Hatmana material before Shabbos, and hence it would make no difference as to why he insulated it.

[17] Seemingly this applies even according to Admur as perhaps we follow his ruling in the Mahadurah Basra only to be stringent not to cover the pot on Shabbos and not to be lenient to allow covering the rest of the pot on Shabbos if the top was covered before Shabbos. Vetzrauch Iyun!

[18] Aruch Hashulchan 257:20; Shabbos Kehalacha; Piskeiy Teshuvos 259 footnote 1

[19] Admur ibid; Tehila Ledavid 257:4

^[20] Shabbos Kehalacha Vol. 2 page 64; Piskeiy Tehsuvos 259:1

^[21] Tehila Lidavid 257:4; 259:2; Elya Rabah 259:9 in the name of the Lechem Mishneh [not on the Rambam]

^[22] Shabbos Kehalacha Vol. 2 page 60; See Piskeiy Teshuvos 257:7 footnote 53 that discusses the dispute on this matter

[23] Based on Admur 257:8; 318:14; M”A 257:; Peri Megadim; However see 254:4 which rules it is forbidden to place uncooked foods on top of an insulated pot; Tehila Ledavid 254:4 establishes the case there to be referring to a pot that is on the fire and is insulated in a permitted way, such as with a board over the top of the pot, and the insulation is thus not touching the walls of the pot.

Other opinions: Some Poskim rule it is forbidden to add or reinsulate whenever the food is not fully cooked even if it is not on a source of heat. The reason for this is because the insulation delays the cooling down of the food and during this time the food is able to cook more. [M”B in Biur Halacha 257:4 “Gorem Lah”; Beis Meir; Nehar Shalom; Mor Uketzia]

[24] Admur 318:14; Shevisas Shabbos Mevashel 105; Chazon Ish 37:17

Other opinions: Some Poskim rule it is permitted to do so. [M”B 318:51; See Minchas Shlomo 2:34-18; Piskeiy Teshuvos 257:8]

[25] See Piskeiy Teshuvos 257 footnote 54

[26] Admur 257:9; Michaber 257:5; See Piskeiy Teshuvos 257:9

[27] Admur ibid; M”A 257; M”B 257:28

^[28] Shabbos Kehalacha Vol. 2 page 52; Piskeiy Teshuvos 257:9; Migdanos Eliyahu 1:83; Chut Hashani 257:6

[29] The reason: As even according to those Poskim that are stringent by a Davra Gush, nevertheless he has performed which cools off the food and hence there is no longer a worry that he may forget that it is Shabbos due to his desire to heat up the food.

^[30] Kuntrus Achron 257:1 “Even if it does not cool it off”; Peri Megadim 257 M”Z 5 in opinion of Rambam; Givas Levona 25; Keren Ledavid 1:77; Zekan Ahron 2:14; Darkei Chaim Veshalom 421; Ketzos Hashulchan 71 footnote 36; Chelkas Yaakov 84; Or Letziyon 2:17-11; Igros Moshe 1:95; Betzeil Hachochmah 2:74; Beir Moshe 1:12; Minchas Shlomo 2:8; Tzitz Eliezer 11:29; Chazon Ish 37:32; Even Yisrael 9:8; Shabbos Kehalacha Vol. 2 page 66; Piskeiy Teshuvos 257:9

Other Poskim: Some Poskim are stringent based on the opinion of Rashi that requires cooling down, to prohibit the use of a thermos being that one does not intend to cool off the water. [Levushei Mordechai 2:55; Tzafnas Paneiach 2:27; Melamed Lehoil 1:45; Shevet Halevi 1:93] Even one who desires to be stringent can simply avoid filling the water until the top [Pnei Shabbos in name of Divrei Yatziv] or through pouring the water into a Keli Sheiyni and then into the thermos. [Levushei Mordechai ibid].

[31] The reason: A the thermos is considered a Keli Sheiyni, and the Sages did not decree against it even if it does not cool off the food. [Igros Moshe ibid based on Rambam] Furthermore, doing so is permitted even according to Rashi that requires cooling down, as the entire prohibition is in covering the thermos, and it is permitted to cover it just like it is permitted to cover any vessel. [See Igros Moshe ibid; Chazon Ish ibid that there is never a prohibition in pouring from one vessel to another even if it insulates]

[32] Piskeiy Teshuvos 257:9

[33] Piskeiy Teshuvos 257:9; Shabbos Kehalacha 11 footnote 68

[34] P”M 257 M”Z 5; Implication of Admur 257:9 “And the Sages only prohibited in the Keli Rishon that it was cooked in”. See Shabbos Kehalacha 11 footnote 68

[35] Chazon Ish 37:32; Piskeiy Teshuvos 257:6

[36] The reason: As there is no prohibition of Hatmana in pouring from one vessel to another even if it insulates, and the entire prohibition of Hatmana is to take insulating material and wrap it around the vessel.

[37] Piskeiy Teshuvos 257:9

[38] Admur 257:2; Michaber 257:1; Shabbos 51a

The reason: This is due to a decree that perhaps when one comes to remove the pot from the stove in order to insulate it with material that does not increase heat, he will find that the pot is cold, and will forget that it is Shabbos and reheat it on the fire, hence being liable for [the prohibition of] cooking.

Other opinions: Some Poskim rule that the reason insulating on Shabbos is forbidden is because one may come to insulate in ember. [Rambam Hilchos Shabbos 4:3; See Lechem Mishneh ibid]

[39] Admur 257:9; Michaber 257:5

^[40] Kuntrus Achron 257:1 “Even if it does not cool it off”; Peri Megadim 257 M”Z 5 in opinion of Rambam; Givas Levona 25; Keren Ledavid 1:77; Zekan Ahron 2:14; Darkei Chaim Veshalom 421; Ketzos Hashulchan 71 footnote 36; Chelkas Yaakov 84; Or Letziyon 2:17-11; Igros Moshe 1:95; Betzeil Hachochmah 2:74; Beir Moshe 1:12; Minchas Shlomo 2:8; Tzitz Eliezer 11:29; Chazon Ish 37:32; Even Yisrael 9:8; Shabbos Kehalacha Vol. 2 page 66; Piskeiy Teshuvos 257:9

The reason: As the thermos is considered a Keli Sheiyni, and the Sages did not decree against it even if it does not cool off the food. [Igros Moshe ibid based on Rambam] Furthermore, doing so is permitted even according to Rashi who requires cooling down, as the entire prohibition is in covering the thermos, and it is permitted to cover it just like it is permitted to cover any vessel. [See Igros Moshe ibid; Chazon Ish ibid that there is never a prohibition in pouring from one vessel to another even if it insulates]

Other Poskim: Some Poskim are stringent based on the opinion of Rashi that requires cooling down, to prohibit the use of a thermos being that one does not intend to cool off the water. [Levushei Mordechai 2:55; Tzafnas Paneiach 2:27; Melamed Lehoil 1:45; Shevet Halevi 1:93] Even one who desires to be stringent can simply avoid filling the water until the top [Pnei Shabbos in name of Divrei Yatziv] or through pouring the water into a Keli Sheiyni and then into the thermos. [Levushei Mordechai ibid].

[41] M”B 326:6 in opinion of Rashi and Admur 326:5 who only records Rashi’s opinion

The reason: As there is now no suspicion that it will spill. As well, there is no medication prohibition involved here as is seen from the fact that Admur ibid makes no mention of it.

Other opinions: According to the reason of Tosafus, even a closed bottle is forbidden to be placed on the body, as it is considered Refua. [M”B 326:19 in name of Karban Nesaanel] Thus, some Poskim rule one may only be lenient on Shabbos in a time of great need or pain. [M”B 326:19; Beir Moshe 1:33-15]

[42] 257:9; 318:23; Michaber 257:6; See Piskeiy Teshuvos 257:9

^[43] Admur ibid [parentheses in original]; see also Kuntrus Achron 1 that leaves in Tzaruch Iyun; M”A 257:14 “Its possible…”; M”B 257:31 [Allows in case of need];

May one rely on this even initially? Some Poskim rule one should only be lenient to insulate food, which is still hot but not Yad Soledes, within the original pot, if it is a pressing situation. [Mishneh Berurah 257:28; Admur here places in parenthese and in Kuntrus Achron 257:1 he leaves this ruling with a Tzaruch Iyun] Rav Farkash rules likewise being that even the Alter Rebbe placed this ruling of the Magen Avraham in parentheses. [Shabbos Kehalacha Vol. 2 page 53] Other Poskim are lenient even initially. [Chazon Ish 37:31; Shevet Halevi 8:166; see Piskeiy Teshuvos 257:10]

^[44] However, if the material adds heat to the food, even if it is not defined as a material that adds heat, it is forbidden. [Mahadura Basra for chapter 259; p. 878 in new Shulchan Aruch; see however 318:23 that one may immerse a bottle of cold water completely in a Keli Sheiyni; Shabbos Kehalacha Vol. 2 page 54-55 concludes as Mahadurah Basra that it is forbidden.]

^[45] Mahadura Basra for chapter 259 p. 878 in new Shulchan Aruch; M”B 258:2; Sheivet Halevy 5:31; Shabbos Kehalacha Vol. 2 page 65; Piskeiy Teshuvos 258:2

Ruling of Admur in Shulchan Aruch: In 318:23 Admur rules that one may immerse a bottle of cold water completely in a Keli Sheiyni. Likewise in 254:4 Admur implies that if a food is fully cooked one may return the insulation even if it is on top of a hot pot, hence implying that one may add heat. However, see Tehila Ledavid 154:4 that establishes this case to be referring to a pot that is on the fire and the insulation was done over a wood board and is hence not defined as insulation at all. Based on this one cannot bring a proof from 254:4 regarding how Admur would rule regarding actual insulation 

[46] M”B ibid

^[47] M”B ibid “if top is revealed”; Sheivet Halevy 5:31 and other Poskim based on the rules explained in this chapter.

[48] M”B 258:2 regarding if one’s intent is to heat up the food and Shaar Hatziyon 258:7 regarding if one’s intent is simply to remove its coldness; Sheivet Halevi ibid

Other opinions: Some Poskim rule it is forbidden in all cases to submerge the bottle even if one’s intent is simply to thaw it down and not add heat. [Chazon Ish 37:17]

^[49] See Piskeiy Teshuvos ibid

Bookmark