Q. I heard that Horav Miller Shlit’a ruled that if you are burning little pieces of chometz that may not contain each separate one the full size of a kezais as required, you should place all those small pieces in a container that will be metzaref (join) them as one. Since if you place them all in a bag, the bag that joins them will burn first, what should one then do?
A. Horav Shlomo Miller’s opinion is that if the fire is contained, as is often done inside a metal drum, that drum is a utensil that will be metzaref the small pieces into a kezais that you place inside. If one does not have such a drum. he can use an aluminum disposable baking tray, where he may place the pieces of wood etc. to fuel the fire, and that tray will serve as a unifying container. The Rov added that when the pieces are inside a paper bag at the beginning of the burning it is considered as being a complete kezais.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit’a