Cracks in the firebox or ring

The firebox or fire ring has cracked

The 2019 FAQ: the slots are expansion joints, and stress cracks "are not a defect". A cracked piece usually does not crack further, and the cook is not affected. Keep using it; replace a segment that has broken apart.

Older LeChefs (before 2016) had a one-piece firebox and a cast-iron coal divider. If the divider sat tight, its expansion could burst the firebox; Monolith sent a shortened divider (2019 FAQ). The Pro 2.0's divider is in the stainless basket.