(Had to remove images as they didnt work. See link above for them)
I made this guide to help my guild with progressing their processing to be able to make ingots. I went further than that and went all the way to the progression quests for Gathering as well up to the level 15 quest.
If you follow the guide, eventually you'll see I say you should be able to smelt ingots now with Heating. I say this because once you turn the water quest in, he gives you the "Heating: Beginner" skill. This is all you need to smelt ingots using your own processing ability Heating instead of using your workers.
I wanted to do this because I wanted to know how to smelt without using a worker, and all guides were from the Korean version, in Korean. So here's an English one! Hopefully this isn't a dupe, and if it is...oh well :)
I'm unsure on actual player levels required, I did this at 37.
He gives you a wheat seed and asks you to plant it. Go around the corner and plant it by selecting the seed in your inventory and right clicking to use it. A plot will show up on your screen, place it and place the seed within it
Wait the 20 minutes and harvest the wheat and give it to him.