The first step was to clean up the components. This machine had been sitting with water in it for quite a while. There was a lot of scale buildup that needed to be cleaned up before I was going to taste anything that came out of it. So, I disassembled the whole machine and put all of the parts in a bath of hot Citric acid for several hours.

It came out very clean. You can see at the bottom of the heat exchanger where the fitting has become detached due to a failed weld. This was the culprit of the leak, and was easy enough to repair myself without having to buy any parts.