Hi,
I just found out that unlike other recipes taking fluroketone, the returned hot fluoroketone in this recipe is applying the productivity bonus from modules. It means that with enough productivity, it can be exploited to actually output more fluoroketone than what is input.
In other recipes taking fluroketone (ex: cryo science), productivity bonuses are applied on all output except hot fluoroketone to prevent this kind of exploit. I think your recipe should mimic this behaviour.
Thanks

Update: I just found out another recipe with a similar problem.
In the 'Biter egg from petroleum gas' recipe, an empty barrel is returned with 90% probability.
I am playing with the 'Wolverine's Productivity Research' mod which contains an 'Egg Productivity' infinite tech. I just noticed that the productivity bonus is also applied to the returned barrels, which lead to the recipe actually generating barrels. This should probably be fixed in the same way.

Thanks for notifying me :D, this will be fixed as fast as possible.