it is fine from 40 to 38 psi in 15 hours. if it is a slow leak on LP side, it is micro and insignificant, but what worry me it is the HPG lower, by how much?
Almost imperceptible. It was such a small change, that I wondered if it actually changed, or if it was a function of me looking at it at a different angle.
I reassembled everything, and I have had it running into the tank for a couple of hours. So far so good. It is holding its working pressure. We'll see how long the tank lasts.