I've been brewing on and off for about 15 years, but I am new to kegging. I kegged my first brew, set the regulator at 10 psig, and I've been drinking off it for about 5 weeks. It has been going fine. I drink about 1-2 pints a day. In the last couple of days, the beer has started foaming a lot, which I took as a sign of a nearly empty keg. I noticed yesterday, however, that the regulator is at 15 psig. I never changed the setting, and I'm quite sure no one else has fooled with it. I am also sure that this just happened recently, as I glance at the gauges sometimes. The other thing that puzzles me is that the upstream gauge reads nearly empty, as if the CO2 tank is almost out.
Is it likely that I have a bad regulator, or is my tank leaking? The change in pressure setpoint suggests to me the former. I don't know why the tank would hold all this time and then suddenly develop a leak with no change in connections and no one touching the setup, but I guess it's possible.
Thanks for any advice which can be offered,