FML

[dank69]

After thinking this I think what's happening is that blue valve may be leaking slightly. Every drop of water that comes out slowly starts to go down the valve stem, but never makes it down before it freezes as the metal is conducting the cold. Over time it just created an ice dam and then accumulated too much water at the end.

This run has a small ball valve as a shut off too, so think I will need to turn it off at that valve too.

I wonder if they make air compressor quick connect fittings that go on standard pumbing fittings. I could also blow air into the lines to ensure there's not a single drop of water left.

Speaking of bad situations though I saw two plumbing company trucks at my neighbor's house. I have a feeling one of his pipes actually burst.

You don't need to make sure every drop is out, you just need to make sure the pipe isn't full or close to full. Even if the blue valve had a slow leak, if you left the outer spigot open you probably would not have had a burst like that. The ice dam theory you have there would never happen; the water pressure would never be high enough. If it were an ice dam the leak would just stop until it melted.

 

[Red Squirrel]

You don't need to make sure every drop is out, you just need to make sure the pipe isn't full or close to full. Even if the blue valve had a slow leak, if you left the outer spigot open you probably would not have had a burst like that. The ice dam theory you have there would never happen; the water pressure would never be high enough. If it were an ice dam the leak would just stop until it melted.

That's what I'd like to think, but I DID leave it open and I DID remove the hose and it is slopped properly. Everything is done right. It was a pro that did it (and I read lot about it online) and I did everything he said. Removing the hose, leaving it open, and opening the little drain plug.