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Steam boiler: main vents and automatic water feeders...
I have a steam boiler system in our house, and had plumber "A" change the return pipes (we are finishing our basement). He installed two main vents in the pipes. Plumber "A" somehow disappeared after appearing on Fox 5 "Shame on you".
The two main vents have been spraying water out of the vents, so I called another plumber, "B". Plumber "B" initially identified an issue with a pressure that was too high in the system (he lowered this from 12 to 2 psi). He also capped off the vents, since according to him proper radiator vents are sufficient and main venting is only necessary on larger steam boilers (he mentioned apartment buildings as an example)
My question is: is that correct?
Also, he advised against installing an automatic water feeder, since it's harder to identify an issue (during the winter we normally have to refeed every 2-3 weeks). What are your thoughts?