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17. Issur which fell into one’s food on Shabbos:
It is forbidden to nullify a non-Kosher food within Kosher food on Shabbos, even in those cases that doing so is allowed during the week. It is however permitted to measure whether a food has sixty times against the forbidden food. Likewise a Rav may Pasken in whether a food is Kosher or Treif.
Q&A on covering a pot of food that is on the fire or that is not fully cooked:
May one place a cover onto a pot of food that is on the fire?
If the food is fully cooked one may place the cover onto the pot. However if the pot is not currently boiling and placing back the cover will cause it to re-boil, then there is room to be stringent, although one who is lenient certainly has upon whom to rely.
If, however, the food is not fully cooked placing the cover on the pot is forbidden according to all. Even when the food is fully cooked one must beware not to return the cover to the pot if the cover is wet [which is very common due to vapor] unless the moisture of the cover is still hot, or one dries the cover.
May one remove a cover from a food that is on the fire and then place it back on?
One may remove the cover in all cases even if the food is not fully cooked. Returning the cover back onto the pot follows the same laws as the previous answer. One must especially beware not to return the cover to the pot if the cover is wet [which is very common due to vapor] unless the moisture of the cover is still hot, or one dries the cover.
May one remove the cover from a pot food that is on the fire on Shabbos and then place it back on?
Removing: One may always remove the cover of a pot of food on Shabbos even if the pot is sitting over a fire, or Blech, or electric plate. This applies even if the food is not fully cooked. The question however is asked regarding whether it is permitted to then replace the cover back onto the pot.
Replacing the cover onto the pot: If the food in the pot is fully cooked then one may replace the cover onto the pot even while it is sitting in the fire, and so is the custom. However, if the pot is not currently boiling and placing back the cover will cause it to re-boil, then there is room to be stringent, although one who is lenient certainly has upon whom to rely. If, however, the food is not fully cooked placing the cover on the pot is forbidden according to all.
Making sure that the inside of the cover is dry, or still warm, by them time is replaced: Even when the food is fully cooked and one is thus allowed to return the cover onto the pot while it is on the fire, one must beware not to return the cover to the pot if the cover is wet [which is very common due to vapor] unless the moisture of the cover is still hot, or one dries the cover. [A simple solution to keep the cover from cooling off is to sit it on the Blech.]
May one place a cloth or the like on a pot that is on the fire and insulate the pot in a way that does not pose a Hatmanah prohibition?
May one return a cover to a pot of non fully cooked food that is off the fire?
May one place a cloth or the like on a pot of non fully cooked food that is off the fire?
According to Admur it is permitted to place it on the side of the pot. According to the Mishneh Berurah it is forbidden.
May one move a pot of food that is on the blech to a hotter spot?
If the food is not fully cooked, it is prohibited.
If the food is fully cooked: See the laws of Chazara
Q&A which relate to electrical heating systems:
May an electric water urn be used for Shabbos?
The water is heated based on a thermostat: Some Poskim rule a thermostat based electric water urn may not be used on Shabbos as the amount of water that is in the pot effects when the heat will turn on and off. It is thus forbidden to remove water from it on Shabbos [even when the heat is on, as nevertheless this will cause the heat to turn off earlier than expected, and certainly when it is off, as this will cause it to turn on]. Other Poskim however rule it is permitted to be used.
Shabbos mode-The water is not heated based on thermostat: A non-thermostat based electric water urn may be used on Shabbos. Such an urn is commonly known as a Shabbos mode urn, which is an urn that has a Shabbos mode option that makes the heat turn on periodically, and not based on temperature.
Heating the water before Shabbos: In all cases, the water in the electric urn must be heated to half its heat [i.e. to at least 50 Celsius/122 Fahrenheit] before Shabbos [sunset] begins, and hence one must make sure to set it up and turn it on with enough time before sunset for it to heat up to this amount.
An urn which has its valve on its bottom in a way that it is possible to remove all the water from inside: It is forbidden to use a water urn that contains a bottom valve through which one can us to completely empty the urn of water unless a) The urn simply insulates the heat of the water and does not further heat it [i.e. Shabbos mode]; b) There is a transparent measuring area which tells one how much water is left in the urn; c) The valve is slightly above the bottom of the water. Nevertheless, in all cases one is to beware not to remove all the water from the urn, as this can cause damage to the urn, or causes the safety feature to shut off the heating element.
May urns with a transparent water level measurer be used on Shabbos? Some Poskim rule one must block water from entering into the water level tube. Other Poskim rule it is permitted to be used on Shabbos.
May one open or close the windows of his house if this will cause the air conditioner or heater to turn on or off earlier than expected?
Yes. This applies even if there is a difital temperature reader that will be affected by one’s opening of the door. However a Baal Nefesh should make sure that a single window is always left open.
May one open the door of his fridge if it will cause the motor to turn on or last longer?
This matter is disputed amongst the Poskim. Practically it is best to only open the fridge while the motor is on. While the motor is off one should be stringent against doing so being that it will cause the motor to turn on sooner. The scrupulous are stringent to attach a timer to the fridge and only open it while it is off, on the timer. This thus prevents any problem of starting up or continuing the motor. Those that are lenient to open the fridge
Shabbos Fridges: Today there are special Shabbos fridge settings that come with fridges which effect that on Shabbos the fridge does not work on temperature basis but on time basis. Such a fridge which had its Shabbos setting turned on before Shabbos may be opened even when the fridge is off.
It is forbidden to open or close the door of the fridge if the fridge light was left active, and will inevitably turn on or off upon being opened or closed. This applies even if all one’s Shabbos food is in the fridge. Thus, if one opened the fridge and then realized the light was left on, it is forbidden to close it.
A gentile: It is permitted to ask a gentile to open the door of the fridge even if the fridge light was left active and will inevitably turn on upon being opened. This applies even if one will benefit from the light turning on. This applies even if one can make do without opening the fridge and the matter is not a great need. Some Poskim write that it is best not to tell the gentile about the light, and rather to simply ask him to open it. It is likewise permitted to ask the gentile to close the door. In order to be able to open the fridge the remainder of Shabbos without needing to ask the gentile each time to open and close it, one can either: a) One may hint to the gentile to remove or deactivate the light bulb. [Some Poskim rule one may even ask him directly to remove the bulb, if one needs to continuously open and close the fridge for the sake of one’s Shabbos food. According to Admur, however, it is forbidden to directly tell him to remove it and it may only be done through a hint.] or b) One is to leave the fridge door slightly open through placing a towel and the like in-between, and thus leave the light constantly on.
A child: It is forbidden to ask a child to open the fridge even if the child is beneath the age of Chinuch and even if he is a mere infant. Some Poskim, however, permit telling the child to remove the plug from the outlet while the fridge is off. This, however, only applies to old fridges which do not have any electricity working when the motor is off. It is however permitted to place a child that is below the age of Chinuch [less than 3 years old] in front of the door of the fridge [without telling him to open it], and if the child opens it on his own accord one may leave the fridge slightly ajar throughout the remainder of Shabbos.
Question from our readers:
I was reading the article regarding if someone leaves the light on in the fridge on Shabbos you mentioned there that you may ask a guy to open and close the fridge. Furthermore, you may even ask the guy to remove the lightbulb. However, this may only be done in an indirect manner as explained in chapter 307, 7. You mentioned that some hold that you may even ask directly if it is needed for the Shabbos meal, however this is not the opinion of the Alter Rebbe as recorded in 276,8.I would like to understand:
1. Isn’t turning off the light מלאכה שאינה צריכה לגופה which is only a שבות and would be permitted to ask a goy לצורך מצוה?
2. If the Alter Rebbe would not permit directly asking the goy to remove the lightbulb (since it’s not a שבות) why would it be permitted to ask him indirectly isn’t it generally forbidden to benefit from a מלאכה done by a goy on shabbos unless a certain condition is met that the goy is doing it לדעת עצמו להשלים פעולתו.. But otherwise even for the sake of a mitzvah You may not indirectly ask a goy to do a מלאכה ?”
1. Whether Melacha Sheiyno Tzericha Legufa is a Shvus/Rabbinical is a dispute in Poskim, and there is no clear ruling that fully arbitrates like the lenient opinion. Practically, we do not consider Melacha Sheiyno Tzericha Legufa as Rabbinical regarding Amirah Lenachri, and hence one may not ask him to do so even Letzorech Mitzvah
2. You are correct in the case that there is a tangible direct benefit from which one receives from the Melacha that one may not even hint to the gentile, and many people do not know this Issur and think that every hint to a gentile is allowed. However, here there is no direct benefit and thus there is not an obligation to protest his actions as Admur rules in Kuntrus Achron, and this is the type of example that hinting to the gentile is allowed in. Practically, the Poskim rule that one may hint to a gentile to turn off a light on Shabbos so you can benefit from the darkness, as opposed to hinting to him to turn it on so you can benefit from the light.
Sources on 1: See Admur Kuntrus Acharon 275:2; 278:2; 316:17; 328:3; 334:25; 340:2; 610:7; M”A 307:7; Maharshag 2:54; M”B 302:36; Ketzos Hashulchan chapter 138 footnote 5; Piskeiy Teshuvos 307:10; Amirah Lenachri [Yosef] 2 p. 202-205
Sources on 2: See Admur 305 Kuntrus Achron 1; 307:7; Piskeiy Teshuvos 276:2
May one use a water machine that does not have a Shabbos mode?
Only use when on.
Hot water machine: May never use even when on.
Using Water pipes and faucets that cause a Melacha to happen:
Opening water affects the digital meter: This matter requires further analysis. Practically, while there are sides to permit it, those who are scrupulous try to change the water meter to a non-digital one, and hence circumvent the issue.
Opening faucet turns on pump: If opening the faucet causes an electric pump to turn on, then it is forbidden to open the faucet on Shabbos. Hence, prior to moving into a high riser building, care must be taken o verify this matter and as to how the pump system works.
May one use a hearing aid on Shabbos?
Although some Poskim have questioned its permissibility due to the changes of electric current caused by the voice volume that enters into it, practically, the widespread custom is to permit its use as rule the vast majority of todays Poskim.
May one on Erev Shabbos place food on his electric plate which is not yet on but will later turn on with the timer?
See “The Laws of Chazara” where this question was discussed.
May one on Shabbos itself initially place food on his electric plate which is not yet on but will turn on latter with the timer?
See “The Laws of Chazara” where this question was discussed.
May one adjust the timer of a Shabbos clock on Shabbos?
Some Poskim rule it is permitted to delay the change of whatever is the current status of the timer. Thus if the electricity is now on it is permitted to adjust it that it turn off at a later time than originally set for. Similarly if it is now off it is permitted to adjust it that it turn on at a later time then originally set for. It is however absolutely forbidden to cause the change of action to occur sooner than was set for, whether to have it turn off earlier or turn on earlier. Other Poskim however rule it is always forbidden to adjust a Shabbos clock on Shabbos.
Yom Tov: This matter requires further analysis.
May one adjust the temperature of a heater?
While the heater is off it is permitted to adjust the temperature to have it be heated to a lower temperature than it was originally set for. [Likewise it is permitted to lower the set temperature for when the heater will turn on while the heater is off.] While the heater is on it is completely forbidden to lower the temperature to have it heated to a lower temperature than it was originally set for. To higher the temperature is not to be done at all, even while the heater is on, by gas/water run heaters. However by electric heaters, the heater may be adjusted to reach a higher temperature [however not for it to turn on at an even higher temperature of the house].
May one add water to a humidifier or vaporizer on Shabbos?
Some Poskim rule it is forbidden to add water to any vaporizer or humidifier. Other Poskim rule it is permitted to add water to a vaporizer if certain conditions are met. The following is the law of cold and hot humidifiers according to these Poskim that are lenient:
Cold humidifier: If the humidifier expels only cold air according to this opinion it is permitted to add water to it if the following conditions are met: 1. The machine is still on and will not turn on due to the added water. 2. No lights in the machine will turn on or off due to the added water. 3. The lights in the house will not decrease their quality of light due to this. 4. One may not remove any part of the humidifier in order to enter the water if doing so causes the humidifier to shut off until the part is reinserted.
Hot humidifier: If the humidifier expels hot air it is forbidden to add water to it on Shabbos due to the cooking prohibition. However, it is permitted to add hot water directly from an urn into the humidifier, fulfilling all the Chazara conditions, and provided that all the above mentioned conditions [of a cold humidifier] are fulfilled. Likewise, this may only be done if the water that remains in the container is already cooked.
May one add water to an air cooler on Shabbos?
This has the same ruling as a cold humidifier mentioned above.
Summary of preparing coffee, tea, soup mix, baby formula on Shabbos:
Coffee: Pour the hot water from the Keli Rishon into a dry cup, [unless the cup has water in it which was precooked in which case one need not dry it even if it is now cold] and then pour that water into another cup which contains in it sugar and coffee. With regards to instant coffee, it is best to make it from before Shabbos in order to avoid any suspicion of Molid. Although, from the letter of the law this may too be done on Shabbos in the above way. [The milk may be poured either into the water which is in first cup which is considered the Keli Sheiyni, or into the third cup.]
Tea bags: Same as coffee [with Iruiy Keli Sheiyni], although with regards to removing the tea bag since doing so is questionable if it contains a Borer prohibition, therefore one should remove it using a spoon or pour it out. However, one may not pour out the liquid from the tea bag. [See “The Laws of Borer”]
Tea essence made before Shabbos: May be placed into a Keli Sheiyni, and if still warm may even placed into a Keli Rishon if it was cooked on the fire from before Shabbos [as opposed to merely placed in hot water].
Entering lemon slices into tea: One who is stringent to not do so at all on Shabbos, even in cold water, have what to suspect for. However those which are lenient in this also have upon whom to rely and thus may do so even in a Keli Sheiyni. However even they should be careful not to squeeze any juice out of the lemon, into the tea, within the process of doing so.
Squeezing lemon into one’s tea: Is forbidden due to the Mifarek prohibition. [see chapter 320]
Pouring lemon juice into ones tea: Is allowed in a Keli Sheiyni.
Making soup using soup mix: Same as coffee [i.e. may only be made with Iruiy Keli Sheiyni].
Placing dehydrated vegetables into hot food: Is allowed even in a Keli Rishon [that is off the fire] being that they are precooked in water or smoked. However, if one knows that they are only partially cooked or not cooked at all in water, then they may only be placed in a Keli Shelishi or poured on from a Keli Sheiyni.
Making mashed potatoes using potato puree: With regards to cooking has the same laws as dehydrated vegetables. However, to make it into a thick batter is forbidden due to the kneading prohibition, and even a thin batter may only be made in ways to be explained below with regards to baby formula. See “The Laws of Kneading” for further information.
Baby formula/Materna: With regards to the laws of cooking it has the same laws as making soup mix. [This is with exception to if it contains Quaker in which case if it was not precooked then it may not be mixed with water so long as it is still Yad Soledes]. In addition, by all formulas one must avoid transgressing the kneading prohibition. If made into a very liquidly form, then it has no kneading restrictions involved and may be done even initially. If made into a semi thick liquid, then it may only be done with an irregularity, such as to make it in the opposite manner that it is usually made [I.e. if one first places in the formula then now one first places in the water] as well as that one is to mix it in a different manner than usual. Thus, if one mixes it by shaking the bottle up and down, he is to now shake it by swirling the bottle from side to side and the like. It is absolutely forbidden to make a thick formula.
Baby cereals: If they were precooked [in water or smoked] in manufacturing then it may be placed even in a Keli Rishon. If not, then it follows the same laws as soup mix. [This is with exception to if it contains Quaker in which case if it was not precooked then it may not be mixed with water so long as it is still Yad Soledes]. In all cases one must avoid the kneading prohibition as explained with regards to baby formula.
With regards to immersing a baby bottle in hot water see the laws of Hatmanah chapter 2 Q&A 5.
 Admur 323:10
 Such as by a mixture a Yaveish Beyaveish in which there is majority Heter, one may not add more Heter so there be 60x versus the Issur. [M”B 323:37] However in other cases, such as an Issur fell into a pot accidently, it is forbidden to add more Heter even during the week, even by a Rabbinical prohibition, as rules the Rama in 99:6.
 This applies even if the mixture occurred before Shabbos. [ibid]
 This is not considered as if one is fixing the food, as the Rav is merely revealing to the asker that the food is fixed. [ibid]
 Shabbos Kehalacha Vol. 1 p. 230-232
 Ketzos Hashulchan 124 footnote 10; Shabbos Kehalacha 5:16; See Admur 254:4; 257:8; Igros Moshe 4:74-10 rules that this question depends on the reason behind Meigis, and that according to the reason that it is due to decree that one may come to do so even by uncooked food, then here to it would be forbidden. However according to the other reasons, it would be allowed. The Shevisas Shabbos [Mevashel 81] plainly rules that it is forbidden. His opinion will be explained in the next footnote.
 The Shevisas Shabbos rules that covering even a fully cooked food that is on the fire is forbidden due to “Meigis” mixing. The Ketzos Hashulchan [ibid] however limits this ruling only to a case that covering the pot will cause it to re-boil, as only in such a case is there mixing taking place. Practically the Ketzos Hashulchan leaves this matter in question [even in a case that covering will cause it to re-boil], although leans to be lenient. Rav Farkash in Shabbos Kehalacha [5:16] rules one may be lenient in all cases.
 Ketzos Hashulchan 124 footnote 10
Doing so contains the cooking prohibition being that it hastens the cooking.
 Shabbos Kehalacha Vol. 1 p. 285
 Shabbos Kehalacha Vol. 1 p. 285
 See Shabbos Kehalacha Vol. 1 p. 230-232; Piskeiy Teshuvos 318:56, 58; Igros Moshe 4:74-10 rules that this question depends on the reason behind Meigis, and that according to the reason that it is due to decree that one may come to do so even by uncooked food, then here too it should be forbidden. However, according to the other reasons, it would be allowed.
 Setimas Kol Haposkim Baalei Hashulchan Aruch who all omit any such prohibition despite it being very common; Ketzos Hashulchan 124 footnote 10; Igros Moshe ibid according to Poskim who rule the reason of Meigis has nothing to do with a decree of “Atu Eino Mevushal”; Shabbos Kehalacha 5:16; Mara Deshmaasah 122; Maor Hashabbos 2 Letters of Rav SZ”A 19:1 and Rav Fisher and Rav Elyashiv; Az Nidbaru 1:79; 5:13; Teshuvos Vehanhagos 1:297; Piskeiy Teshuvos 318:58; See Admur 254:4 and 257:8 that one may return fallen insulation onto the pot if the food was fully cooked
Other opinions: Some Poskim rule that it is forbidden to cover a pot of food while it is on the fire even if it is fully cooked, due to the Meigis prohibition and the fact that it appears as if one is cooking, and may come to do so to an non-fully cooked food. [Makor Chaim of Chavos Yair 318; Tehila Ledavid Tinyana 252; Shevisas Shabbos Mevashel 81; Igros Moshe 4:74-10 according to Poskim who rule the reason of Meigis is because of a decree of “Atu Eino Mevushal”; Piskeiy Teshuvos ibid footnote 531] Some Poskim conclude based on this that it is proper to be stringent. [Vayaan Yosef O.C. 159; Igros Moshe ibid; SSH”K 1 footnote 108]
 Ketzos Hashulchan ibid; Rav Farkash in Shabbos Kehalacha 5:16 writes that one may be lenient even in such a case
The reason: The Shevisas Shabbos ibid rules that covering even a fully cooked food that is on the fire is forbidden due to “Meigis” mixing. The Ketzos Hashulchan ibid however limits this ruling only to a case that covering the pot will cause it to re-boil, as only in such a case is there mixing taking place. Practically, the Ketzos Hashulchan leaves this matter in question [even in a case that covering will cause it to re-boil], although leans to be lenient.
 Admur 254:4 and 257:8; Biur Halacha 257:4 “Goreim”; Ketzos Hashulchan 124 footnote 10; Piskeiy Teshuvos ibid and ibid
The reason: Doing so is forbidden due to the cooking prohibition, being that it hastens the cooking.
 Shabbos Kehalacha Vol. 1 p. 285; Piskeiy Teshuvos ibid footnote 533
 Even if some of the moisture accidentally spills onto the Blech and causes it to sizzle, we do not find any recorded prohibition in doing so, as the moisture is already fully cooked and does not contain a looking like you’re cooking prohibition.
 Shabbos Kehalacha Vol. 1 p. 230-234
 Admur 254:4; 257:8; 318:14
 Admur 254:4; Ketzos Hashulchan 124 footnote 10
 Shabbos Kehalacha Vol. 1 p. 230-234
 Admur in 257:8 and 318:14; 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 here 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.
 Biur Halacha 257 “Lo Nisbashel”
 Shabbos Kehalacha Vol. 1 p. 230-234
 Shabbos Kehalacha Vol. 1 p. 135
 See Piskeiy Teshuvos 277:6
 Minchas Yitzchak 5:91; Orchos Shabbos 2:26; Shabbos Kehalacha ibid
 Orchos Shabbos ibid
 SSH”K 1:40 [46 new edition] in name of RSZ”A; Maor Hashabbos 1:12 in letter of Rav SZ”A; See Igros Moshe 4:74 Bishul in which a number of Teshuvos rule that it may be used and no mention is made of any prohibition; Piskeiy Teshuvos 254 footnote 45 one who is lenient has upon whom to rely.
 The reason: As it is a case of Germa Delo Nicha Lei and is not a full Pesik Reishei. [Rav SZ”A ibid]
 Admur 254:14
 This refers to all urns that have adjustable modes, or a switch to turn on:off.
 Igros Moshe 4:74 Bishul 24; Shabbos Kehalacha Vol. 1 pages 317-319; See Ketzos Hashulchan 71 footnote 1; Piskeiy Teshuvos 254:6
 Admur 253:1 “if by the time the night [of Shabbos] begins the dish is still not cooked to the point of Ben Drusaiy.” M”A 253:26; Peri Megadim 253 A”A 26; Rav Akivah Eiger 253; Shabbos Kehalacha Vol. 1 pages 313-314;
 SSH”K 1:40; Piskeiy Teshuvos 318:61; See Minchas Yitzchak 3:137; 5:91; 6:21; Az Nidbaru 7:21; Shevet Hakehasi 3:109; 4:108
 The reason: This is due to suspicion that the water may completely finish and one may come to add more water in order to prevent the urn from burning up. [See M”B 318:117]
 Minchas Yitzchak ibid; Piskeiy Teshuvos ibid
 See Piskeiy Teshuvos 318 footnote 254
 Rav Moshe Yadler in Maor Hashabbos end of volume 1 and Minchas Yitzchak 10:28 [unlike his ruling in 6:21]; Minchas Yitzchak ibid according to those who hold there is a prohibition of cooking by water that was not boiled before Shabbos; So rules Rav Asher Lemel Cohen; and the Machon for Halachic technology
 The reason: The reason for this is because they suspect the water in the tube does not become Yad Soledes and when one releases water from the urn some of that water in the tube consequently enters the urn of hot water and gets cooked. Furthermore, even if it did reach Yad Soledes, some Poskim rule that so long as the water did not reach boiling point it is not fully cooked and retains a cooking prohibition, and hence when one now removes water from the urn it causes the uncooked water to mix in with the cooked water and further cook. [Igleiy Tal in Hashmatos, retracting from his ruling in the “Ofeh” 8; Tehila Ledavid 318:17 and Rav SZ”A in SSH”K 1 footnote 96 leave this matter in question; Sheivet Haleivi 7:42 and Minchas Yitzchak 10:28 lean to be stringent]
 Orchos Shabbos 2:30; Minchas Shlomo 34:23; Shalmei Yehuda 53 in name of Rav Elyashiv; Az Nidbaru 9:14; Shevet Hakehasi 4:108; Or Letziyon 2:30-10; See Minchas Yitzchak ibid that it is possible the water reaches Yad Soledes and hence there is no prohibition according to those who rule that Yad Soledes is already considered cooked.
 The reason: As the water in the tube certainly reaches above Yad Soledes [Piskeiy Teshuvos ibid says it reaches between 55-70 Celsius] and many Poskim rule that once water has reached Yad Soledes it is considered cooked and no longer has a cooking prohibition to further heat. [Igros Moshe 4:74 based on Admur 318:9; Az Nidbaru 9:14 seemingly retracting his ruling in Bris Olam; Olas Shabbos 318:12; Shevisas Shabbos 18; Iglei Tal Ofeh 8] Alternatively, all the water in the urn and valve get mixed during the boiling process, and hence according to all everything is already pre-cooked and no longer has a cooking prohibition so long as it is still warm. [Orchos Shabbos ibid] Alternatively, it is permitted being it is a Safek Gerama and not Niacha Lei. [Minchas Shlomo]
 Minchas Yitzchak 3:24; brought in Piskeiy Teshuvos 326:9
 As besides for the possibility that it is a Psik Reisha which is done indirectly [Grama] and one has no benefit, of which may be done on Shabbos, here it is not even a case of a Pseik Reisha being that one does not know upon opening the door if the heat/air is on or off. [Minchas Yitzchak ibid]
 Piskeiy Teshuvos 277 footnote 51
 Minchas Yitzchak 3:24-18
 See Piskeiy Teshuvos 277; Minchas Yitzchak 2:16; 3:24-14
 Nevertheless this itself is not simple that it is forbidden being that possibly a Psik Reisha which is done indirectly and one has no benefit of may be done on Shabbos. See Minchas Yitzchak ibid which discusses the different sides to the matter
 Minchas Yitzchak ibid
 Beir Moshe 6 Elektri 4; Brought in Piskeiy Teshuvos 320 footnote 20
 Az Nidbaru 2:36
 Igros Moshe 2:68; Beir Moshe Electri 6:9
 Igros Moshe 2:68; Beir Moshe Electri 6:9-10; SSH”K 31:1; Piskeiy Teshuvos 276:15
The reason: As it is permitted to ask a gentile to perform an action which causes a Melacha to occur as a Pesik Reishei. [Admur 253:10 and Kitzur Hilchos Shehiya Vihatmana regarding a gentile moving a pot that is insulated within coals; 259:7 regarding a gentile opening a coal oven; 276:9 regarding gentile carrying candle; 277:5 regarding having a gentile shake a candle off one’s table; 253:28 regarding having him turn on heater and consequently heat food; 331:12 regarding having gentile soak garment in water; So also rule: Michaber 259:7; M”A 253:18; 259:11; 276:10; Hagahos Maimanis 6:20; Maharil 60; Minchas Shabbos 80:109; Tehila Ledavid 336:4; Tiferes Yisrael Kalkeles Shabbos 5:6; Shoel Umeishiv Gimel 3:3; M”B 259:21; 277:15; 337:10; Shaar Hatziyon 255:1; However, see M”B 276:30 and how he is explained in Piskeiy Teshuvos 276:15; See also Bris Olam Amira Lenachri 16 who is stringent by Biblical prohibitions]
Other opinions: Some Poskim question the basis of the validity of this Heter as perhaps the gentile’s action of opening the fridge is in truth not considered a Pesik Reishei after all, but rather a direct act. This means as follows: A Pesik Reishei is when one does an action that unintentionally causes an unrelated second action to occur. If, however one does an action that has dual functions, one of Issur and one of Heter, then one cannot consider it simply a Pesik Reishei when one is doing the action for the purpose of the permitted function, if it will inevitably perform also its forbidden function. This is similar to the switch of a water machine that accomplishes two things when turned on: 1) Turns on the light and 2) Opens the faucet. If one turns on the switch with intent to open the faucet and thus causes the light to turn on, this is not considered a Pesik Reishei but a direct act, being the purpose of the switch is also to turn on the light. [Rav SZ”A in SSH”K ibid and Shulchan Shlomo]
 Tehila Ledavid 336:4 based on M”A 253:41 and Admur 253:28 who allows the gentile to place the food near the heater and then turn on the heater; SSH”K 31:1 footnote 1; Poskim in Piskeiy Teshuvos 276:15 footnote 114
Other opinions: Some Poskim rule that is forbidden to ask a gentile to perform a Pesik Reishei action if one receives benefit from the Melacha that is performed [i.e. Nicha Lei]. [Biur Gra end of 253, brought in Shaar Hatziyon 253:4; Piskeiy Teshuvos ibid; See SSH”K ibid]
 Igros Moshe ibid
 Beir Moshe ibid; See Rav SZ”A ibid
 SSH”K ibid
 Beir Moshe ibid; SSH”K ibid; See Admur 307:7
 Igros Moshe ibid
 The reason: As it is permitted to ask a gentile to perform a Melacha in a time of great need. [Igros Moshe ibid; Opinion in Rama 276:2 and in Admur 276:8; 331:7; 340:2; 446:6]
 Final ruling of Admur 276:8; 331:7; 340:2; 446:6 in Hagah
 Beir Moshe ibid
 Admur 343:5; 265:10; Ketzos Hashulchan 147:3; Beir Moshe ibid
 Beir Moshe ibid
 Admur 340:10; Vetzaruch Iyun from Admur 266:10, and so rules Ketzos Hashulchan 147 footnote 11, that a child even below Chinuch may only be given an object if the adult has no intent for the child to perform the prohibition with that object, while here the entire intent of bringing the child is for him to turn off the light. Hence on what bases is it permitted? Perhaps however one can say that since here one is not placing the item into the hands of the child and is simply placing him near the item, therefore it is more lenient.
 Piskeiy Teshuvos 277 footnote 52
 See Har Tzevi 1:173; Shearaim Hametzuyanim Behalacha 80:40; Chelkas Yaakov 2:41; 3:186; Igros Moshe 4:85; Minchas Yitzchak 1:37; 2:17; 112; 3:41; Tzitz Eliezer 6:6; Minchas Shlomo 1:9; Yabia Omer 1:19; SSH”K 34:28; Orchos Rabbeinu 1:146; Nishmas Avraham 301; Piskeiy Teshuvos 277 footnote 39;
 Shabbos Kehalacha Vol. 1 p. 253 based on ruling of RSZ”A brought in SSH”K 23 footnote 73; See Piskeiy Teshuvos 277:5
 See PT 277 footnote 42; SSH”K 13:25; Eretz Tzevi 1:72; Minchas Yitzchak 2:10; 3:37; Minchas Shlomo 1:13; Tzitz Eliezer 6:5; Yabia Omer 3:18
 The reason: As this is similar to closing a door in front of a candle to prevent it from extinguishing [277:1] or igniting. [277:4] Adjusting the clock does not pose a problem of Mukztah as it is considered MM”I which is permitted top be moved “Letzorech Mekomo”. [Piskeiy tehsuovs 277 footnote 46]
 Igros Moshe Orach Chayim 4:91; Yoreh Deah 3:47; Az Nidbaru 3:25; 8:32; Beir Moshe Elektri 6:26; Betzeil Hachomah 2:32
However, the Igros Moshe [Orach Chayim 4:91] plainly rules that all adjusting of Shabbos clocks are forbidden, whether to make the light turn on earlier or later. He does not give any reason behind his explanation.
 The reason: As it is similar to removing oil or adding oil to a lamp which is forbidden. [265:1] Likewise the clock is Mukztah MMCK. [Piskeiy Teshuvos 277 footnote 46]
 Shabbos Kehalacha chapter 6; Piskeiy Teshuvos 326:9; SSH”K 23:20
 As by doing so one is causing the heater to last for less time when it is anyways not even yet on.
 Meaning one may adjust to have it turn on only later when the house reaches a lower temperature than was set for from before Shabbos.
 As one simply delays it from turning on when it was supposed to.
 As there is suspicion that this will cause some of the water to get heated to Yad Soledes as opposed to if it was left at its current temperature.
 See Shabbos Kehalacha Vol. 1 6:21-22; Piskeiy Teshuvos 318:28; Minchas Yitzchak 7:21; 8:28;
The possible issues involved in adding water to a vaporizer:
- Increasing or decreasing current of electricity [problem of Molid or Kibuiy of the lights which have their current diminished]
- Causing light on machine to turn on or off.
 Minchas Yitzchak 7:21
 The Minchas Yitzchak ibid forbids adding even cooked hot water to a hot vaporizer being that in his opinion this is considered cooking. Likewise, he leans to forbid even cold vaporizers due to Nolad and possibly causing change of current in electricity.
 Shabbos Kehalacha Vol. 1 6:21-22; Hilchos Shabbos Zoreh footnote 64 in name of Rav Moshe Feinstien allows doing so for an ill person; Beir Moshe 6:52 allows doing so through a gentile for the sake of an ill person; Shalmei Yehuda 2:14 in name of Rav SZ”A permits doing so for the sake of an ill person.
 According to them there is no problem of increasing or decreasing the electricity as what Melacha is there involved in making a greater current of electricity. Likewise, the electric current does not decrees the quality if the lights in the house due to a mere amount of added electricity. If, however adding more water to the machine takes a lot of electricity then even in their opinion it would be forbidden to add more water if it causes the quality of light in the house to diminish. [Shabbos Kehalacha ibid footnote 33]
 See previous footnote
 Hilchos Shabbos Zoreh footnote 64 in name of Rav Moshe Feinstien and Shalmei Yehuda 2:14 in name of Rav SZ”A permit adding water only through a water hole and do not allow one to remove any parts to enter the water. Vetzaruch Iyun as the logic of this ruling. Seemingly those machines that they referred to would shut off when the water container was removed and hence if removing the container will not shut off the machine then it is allowed to be done. [Shabbos Kehalacha ibid footnote 33]
 Thus, one must pour the water directly from an urn without removing it with a utensil. [Shabbos Kehalacha ibid]
 Otherwise adding removing it and then reinserting it is considered cooking the water. [Shabbos Kehalacha ibid] Likewise one may not pour from a Keli Rishon on to such water. [Shalmeiu Yehuda ibid; However, see Shabbos Kehalacha ibid Biurim 6]
 Piskeiy Teshuvos 318 footnote 85
 Piskeiy Teshuvos ibid concludes that he heard from many great Moreh Horaas that they permit adding water to an air cooler on Shabbos.
 Based on Shabbos Kehalacha chapter 7
 Regarding Turkish coffee, see Piskeiy Teshuvos 318:36 and the compilation at the end of this chapter
 The Minchas Yitzchak [4:99] compares doing so to placing whole grapes into wine on Shabbos so they break and seep out juice, which according to Admur is not to be done initially. [Although the Minchas Yitzchak himself rules that it is allowed.]
 Shabbos Kehalacha Vol. 2 p. 408. As the custom today is to prohibit squeezing lemon into liquids, as will be explained in The Laws of Squeezing Halacha 3 Q&A there.
 So is the opinion of Admur in the Siddur. However according to the M”B [and Admur in the SH”A] it may be placed in a Keli Sheiyni unless one has knowledge that this specific soup mix had not been precooked during the manufacturing, in which case according to all it would only be allowed with Iruiy Keli Sheiyni.