Vessels made from earthenware that were used for chametz cannot be kashered by immersion in boiling water, nor by heating with charcoal or blow torch. Ovens and stoves made of stone and bricks can be kashered by heating with charcoal (or a blow torch) (see above Chapter 110, par. 1 and 2). It is customary not to Kasher stoves used for heating the house during the winter. If you want to place any kind of a dish on the stove, during Pesach, you must first put a metal plate on the stove and then place the dish on it. This method may be used also with an oven made of tiles.

Vessels made of wood, metal, stoneware or bone, can be kashered by immersing them in boiling water. But vessels that will be damaged by boiling water, such as vessels that are glued together, even if only the handle is glued on, cannot be kashered by immersion in boiling water,¹ 451:23) because we are concerned that they will not be kashered properly.

footnotes: ¹ This also applies, if the handle is made of any substance, that will be damaged by immersion in boiling water. (Mishnah Berurah

Before kashering a vessel, you must clean it thoroughly to remove any rust,², by using charcoal or a blow-torch, you need not remove the rust, because the flame or heat will also remove the rust. (Ibid. 451:24) or similar residue, making it perfectly clean; but rust stains do not matter.³ If the vessel has dents, they should be scraped carefully (with steel wool etc.). If it is made of metal, you should place hot charcoal on the dents (or use a blow torch) to "glow" them, and then kasher the vessel with boiling water. If it is impossible to thoroughly clean the dents and the cracks, and if it is also impossible to "glow" them, then the vessel cannot be kashered.⁴. (Ibid. 451:26; See also Kitzur Shulchan Aruch, paragraph 10) Therefore, knives with handles must be carefully examined⁵. (Ibid. 451:23) to determine whether they can be kashered. The best way to do the mitzvah, if you can afford it, is to buy new knives for Pesach.

footnotes: ² If, however, you are kashering ³ This refers to other stains as well. ⁴ Similarly, vessels, with a very narrow opening, that have rust in them, cannot be kashered ⁵ Handles, that are attached with nails or screws, cannot be kashered

Vessels that are used over fire (or heat), without water, require glowing. Therefore, baking and frying pans, in which chametz was baked,⁶ was never baked in them, it is sufficient to immerse them in boiling water. (Ibid. 451:27) require glowing. Initially, the vessel must be heated so intensely, that it shoots off sparks. A wooden peel cannot be kashered.

footnotes: ⁶ If, however, they were used for meat or fish and you are certain that chametz

If a vessel has a patch, and there is reason to suspect that underneath the patch, some chametz may have become trapped, that place must first be glowed until you are certain, that if there was a trace of chametz, it was burned; and then it should be kashered in boiling water. But if there is no reason to suspect that a trace of chametz was trapped there, then, if the patch was put on before the vessel was used for chametz, you may kasher it as is, because, just as the vessel absorbed the chametz, so it will expel it with the boiling water (used in the kashering)**. However, if the vessel was first used for chametz, and the patch was put on afterwards, then the kashering has no effect on the place underneath the patch, and in this case, too, before kashering, you must place hot charcoal on the patch, to glow that spot. If the patch was soldered with lead, silver, or similar solder, it may be kashered as is, since the chametz that has been absorbed, was burned by soldering.

A mortar, which is ordinarily used for pounding sharp tasting spices together with chametz, requires libun kal —"simple glowing", that is, it should be filled with burning charcoal, until it is hot enough to burn a piece of straw placed on the outside of the vessel. But in a community, where it is customary to pound in it, only pepper and similar spices, kashering with boiling water is sufficient.

In vessels that were used to age whiskey, the taste and aroma of the whiskey is not eliminated by kashering with boiling water. Only if you first boil them thoroughly in water and ashes, until the aroma has disappeared completely, can they then be kashered in boiling water.

The kashering of a barrel, should be done as follows: place heated stones in it, and pour boiling water on them out of the vessel, in which the water was boiled; then roll the barrel, so that the hot water will reach every part of it. The type of barrels which we use, are made of many planks hooped together and if they contained chametz, such as whiskey, or if flour, kashering is of no avail.

When a vessel requires kashering with boiling water, merely scouring the surface is of no avail,⁷. (Ibid. 451:26) it must be immersed in boiling water.

footnotes: ⁷ Because the entire thickness of the walls have absorbed the chametz

Kashering is of no avail regarding vessels that cannot be thoroughly cleaned, such as a sieve, the receptacle of a grinder, baskets used for keeping chametz, a grater, as well as any vessel that has a narrow opening, which is impossible to clean on the inside, (or a vessel) that has a spout.

A cabinet, in which food is kept⁸. (Ibid. 451:113) the entire year, and soup is sometimes spilled there from the pots, requires simple kashering, that is pouring boiling water on it;⁹, are sometimes placed there, they require that hot stones be placed on them, (similar to kashering tables, that are discussed in this paragraph). (Ibid. 451:114) but it must be poured out of the vessel, in which the water was boiled.¹⁰. 451:20) The water should not be thrown, but it should be poured in a steady stream. (As for kashering) tables, it is also customary to place glowing hot stones on the table, and pour boiling water on them, and then to move the stones from place to place in such a manner, that the boiling water covers the entire surface. The table must be scrubbed first, and after twenty-four hours, it should be kashered, in the manner described above. Nevertheless, some people are accustomed, not to use tables and chests even after kashering, without covering them with a cloth or something else.

footnotes: ⁸ This is only when hot foods are kept in them, but otherwise, they do not require kashering ⁹ Others hold that since hot puddings, that contain chametz ¹⁰ You must not use another vessel to dip into the vessel containing the boiling water and then pour it onto the surface from the second vessel. (Ibid

Handles of vessels also require kashering. However, if the handle does not fit into the kashering pot, you should kasher the handle, by pouring boiling water on it.¹¹; pouring hot water over them will not help, but they must be kashered in the regular way by immersion, then in boiling water. (Ibid. 451:71)

footnotes: ¹¹ However, if you know, for certain, that the handles were immersed in boiling liquid, containing chametz

Vessels used for drinking or measuring, also require kashering.¹² drinking glasses. If they have not been used during a twenty-four hour period, you may fill them, even with cold water, allowing the water to overflow, and then leave the water in the glasses for twenty-four hours. After twenty-four hours, you spill out the water and refill the glasses with new water. After twenty-four hours, you spill out the water and repeat the process a third time. This need not be done in consecutive days, so long as it was repeated thrice, as outlined. (Ibid. 451:150) As for glassware, it is the custom in these regions not to kasher them.¹³ writes that you may rely on the kashering, described in note 12 above. (Ibid. 451:156) Vessels made of metal, glazed on the inside, cannot be kashered by immersion in boiling water; but "simple glowing" is sufficient, just as with a mortar, see par. 6.

footnotes: ¹² There is another method for kashering ¹³ In a situation where new glasses cannot be purchased, and you have no other drinking vessels, the Chayei Adam

Only water should be used for kashering, and nothing should be mixed with it, not even ashes or similar substances. If you kashered many vessels in one kashering kettle, so that the water became thick and filmy like soup, you should not continue to kasher with it.

If you kasher, using a pair of tongs, to hold the vessel, you should relax your hold on the vessel, and then grip it firmly again; otherwise, the kashering water would not reach the spot held by the tongs. It is better to put the vessel in a net or in a basket. You should not put many vessels at one time into the kettle in which you kasher, so that they should not touch each other; otherwise, the place where they touch, would not be kashered.

You should not kasher a vessel that has been used the same day, that is, unless twenty-four hours have passed, since chametz was cooked in it. Likewise, the kettle, in which the kashering is done, should not have been used that same day. You should pay attention that the water is still bubbling when you put a vessel in the kettle. If the kettle, itself, has to be kashered, then, when the water is boiling, it must be full and you should throw glowing stones into it, so that the boiling water will overflow its rim. On erev Pesach, kashering must be done, only until midday.

It is customary, after kashering, to rinse the vessels with cold water.¹⁴ vessel. (Ibid. 452:34)

footnotes: ¹⁴ This should be done immediately, so that the vessel will not absorb the boiling water of the kashering

If possible, the kashering should be done in the presence of a Torah scholar, who is well versed in the laws of kashering.