Is it permitted to cook/boil purchased dairy equipment liquid in a meat equipment pot? Does the liquid or the pot become treif or are both kosher?
If the liquid is parve, i.e. it does not contain any dairy ingredients, and it was cooked using dairy equipment, it is allowed.
All the best
Pri Megadim Mishbitzos Zahav Y:D 95:5, Hashmatos Rav Akiva Eiger Y:D 95:2