Factorio Forums

First post and first bug report!
I think this bug from viewtopic.php?t=8275 has popped up again.
As you can see here, if there is steel in the output slot of the furnace, the inserter does not insert anything other than iron plates into the furnace.

However if you take out the steel from the output slot, the inserter will attempt to put any other smeltable item into the furnace, resulting in a stuck system.

kovarex wrote:[...] when the furnace is already smelting (using some recipe), it will only accept the item if it matches the recipe in use.

So it seems that since there is not enough iron to start steel smelting the inserter starts inserting ore again.
Ill keep this open as the fix sounds inconsistent to me, but you should sort your ores before smelting never the less.

We had a lengthy discussion about this a while ago, where we established that this is an issue with how the furnace type entity works and when I remember correctly the answer a dev gave was "working as intended"

Do you have the link to that discussion?

Arch666Angel wrote:viewtopic.php?f=23&t=21993

Ill file this as duplicate then.