Thanks for the sucker advice! Definitely need to catch, identify, and perhaps eat.
Oh... I have no idea if the OPV will whistle at me when/if it pops. It looks like your garden variety OPV that would be found on
an air compressor, but I can't imagine that the volume/pressure our diffusion pumps run at would cause it to make much noise.
I have seen high-pressure OPVs that are spring loaded on gas pipelines. They typically have a little disk that blows out of the vent port when they open due to overpressure, or have a thin wire attached that breaks when the stem moves on the relief port.
I was just wondering if you could make some "poor boy" version of that? Maybe just lightly obstruct your pressure relief port with a dowel or similar item that would easily blow out if you hit overpressure. That way you would at least know that something was plugging in your system.
