They are not commonly replaced, unless there is obvious corrosion or damage; and my regulator was "asymptomatic," though I was, by that time, probably in the shallows; I cannot be certain. That incident was my only spring-related failure; and I very carefully examine them now, when I service regulators.Do you recommend replacing the spring at specific intervals? Probably not an issue for a 5 year old regulator, but how about at 10 or 15 year old regulator? Does the regulator exhibit any symptoms prior to failure?
O.
That tech (I wasn't servicing my own gear back then), I recall, handed me two neatly sheared pieces of the main spring, along with the comment that the IP actually remained within specs, just with the secondary in place . . .