David wrote:
On Sep 3, 6:07 pm, David wrote:
SNIP

The pressure could be a problem. I had a PEX joint start to leak
about a year ago, and the plumber (who didn't have a pressure gauge)
turned down the pressure regulator at the main shutoff (it was wide
open). Perhaps it needs to be turned down even further.


You misunderstood. The pressure regulator *is* the problem.
They contain a check valve which prevents the expansion
pressure from dumping back to the city main. That's why
the expansion tank is needed.

But do the bucket-under-the-relief test before doing anything.

Jim