Siman 435

If he did not search on the night of the fourteenth—he shall search during the day whenever he remembers. And if he remembers before the sixth hour—he shall search and nullify. And at the sixth hour he shall search and burn. And he shall not nullify, for it is no longer in his possession, as it is forbidden for benefit. And he must search by the light of a candle just as at night. And if he did not search on the fourteenth day—he shall search throughout the days of Pesach, and even on the Yom Tov itself, and even if he nullified before Pesach. And he does not violate "bal yera'eh," nevertheless we decree lest he come to eat from it. However, on Yom Tov when it is forbidden to burn it—he shall overturn a vessel upon it until night, and at night he shall burn it (Magen Avraham and Taz). And why do we not decree that he might come to eat during the time of the search? Because this is not a concern, since he is occupied with its removal—he will remember and not eat. And even on the final Yom Tov—he must search (ibid.). And there is one who says that on Yom Tov he should not search (Bach), and it is not the primary view.

And if he did not search during the festival, he is obligated to search even after Pesach, so that he does not stumble upon chametz that remained over Pesach, which is forbidden for benefit. And this search also must be according to the enactment of the sages by the light of a candle (Taz). And if he nullified it before Pesach, such that he does not violate "it shall not be seen" – some say that he does not need to search according to the opinion of the author of the Ittur, for when he nullified it – it is permitted for benefit (Chok Yaakov). However, we do not hold like the Ittur.

When one searches on the eve of Pesah, and on Pesah itself—he must recite a blessing, even if he nullified it. However, after Pesah, since the search is only so that he does not stumble upon the prohibition of hametz that remained over Pesah—it is not relevant to recite a blessing. And how could he recite a blessing "on the removal of hametz" while he is eating hametz? And even if he did not nullify it, and violated "it shall not be seen"—nevertheless, a blessing is not relevant for this. And if he searched and nullified according to the law and hametz was found with him on Pesah, or dough became leavened in his possession on Pesah—some say that he must recite a blessing at the time of removal (Hok Yaakov and Mekor Hayyim). And some are uncertain regarding this (Atteret Zekenim and Magen Avraham). And it appears in my humble opinion that the rule of "uncertainty regarding blessings is to be lenient" applies, and the blessing that he recited on the night of the fourteenth—stands for everything that he will search (and so wrote the Gaon Kereti U-Peleti in the book Sar Ha-Elef). And one who did not search for hametz and died at the sixth hour—the heirs shall not recite a blessing. And they search without a blessing, for they are not violating a prohibition, as they do not wish to inherit a prohibited item. And he is dead, and there is no one upon whom the obligation of searching is placed (Hok Yaakov and Mekor Hayyim). And it is obvious that for a minute amount of hametz—one should not recite a blessing, only for a kezayit (Hok Yaakov). (And the Mekor Hayyim wrote that one can appoint an agent even for hametz that he will acquire afterwards, by way of removal, for he removes himself from the hametz. For with hametz, a manifestation of intent is sufficient.)