Thoughts on the modern "Steve's Receiver"

JStar

Just wondering if this was ever a concept for staging steam.



Two separate pressure controllers / vaporstats. Each one controlling the High or Low fire on a two-stage gas valve. Could also add a throttling valve on the manifold to create a third stage. You see it on some new hot-air furnaces.



Does this wind up being too inaccurate? It would really only save the trouble of installing two gas control valves and what appears to be a lot of extra, cumbersome parts.



My other concern was, with lack of useful information, how the two stage gas control operates. I'm not 100% sure if the Low fire coil is energized in High fire mode.