@Override public void setInventorySlotContents(int slot, ItemStack itemstack) { // reset heat if set to null or a different item if (itemstack == null || (getStackInSlot(slot) != null && !ItemStack.areItemStacksEqual(itemstack, getStackInSlot(slot)))) { itemTemperatures[slot] = 0; } super.setInventorySlotContents(slot, itemstack); // when an item gets added, check for its heat required updateHeatRequired(slot); }