Copper Tube Soldering Problems
Okay, so I'm in the process of replacing some old valves in preparation for adding a new water softener bought from a contributor on this list.
I'm new at soldering, but have been soldering with electrics for decades, so it's not that different. Of more than three dozen joints I've made, I have two that are leaking. One leak is horizontal, the other is vertical. Not huge, but enough, especially since they are on the line that goes from the well to the softener.
With every joint I sanded the tubing and fluxed both the inlet and outlet. I use a basic propane torch and solder, both bought at Menards.
I heat up the joint, then let the solder flow into it, just like I've seen on several videos. On these two joints, after they leaked, I resanded, cleaned them with alcohol and refluxed them, but did not take them apart. It seems that no matter how hot the joint gets (other joints six inches away start to soften) , the solder doesn't want to flow into it.
What happened? Do I need to remove these two and start over from scratch?
Is it contaminated somehow?