Thanks. What's sort of interesting to me is that these lines survived the big freeze that we had a few years ago when temps got down to -8 and never got into the 20's for a full week. I had other lines break on me, but not these two.
The one with Ice has been there for at least a dozen years. It's Schedule 40 PVC wrapped in foam insulation, inside a 2 inch PVC pipe that I used as a sleeve. I sort of thought I had it figured out with that combination, but I was wrong.
The other line is Type L Copper, which is what I used in several other outdoor spickets without issue, that also survived the big freeze a few years ago.
I have two spickets that are blue colored PEX that come out of the ground, and up a wood fence post that seem to be fine. I like the idea of protecting them, but I haven't thought of a good way to do that. I'll have to think about that.
For the two that failed, I'll dig down to the supply lines, install a PEX fitting, and run PEX back up the wood posts.
I wonder if snow insulated them when we had the big freeze? We had about six inches of snow when that happened.