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2 pipe crossover trap or air vents ?
Having to possibly re do a decent portion of a 2 pipe steam over including dry returns which route would you go. A bunch of vents on the main and dry return before the drip w a decent water seal or would you forego the main vents on the steam main and use a crossover trap into your dry return and vent the living crap out of it. In this situation the most possible positive outcome would be that the rads basically see steam only after the crossover trap is closed which I would think would be when radiator would start venting. The other way which would be vents both main n return may end having rads on the beginning of the main would be served first. This is a perimeter main n return starting in the boiler room n from what I can imagine at one time ended near the boiler room. Issue is someone but he’d up the last leg of the system install a f n t trap. Discharging into some crazy sort of knuckleheaded return piping it’s all garbage n I know what needs to be done$$$ but the crossover trap over a vent supply has me leaning. So what’s the gang have to say. On a side note it s 2 pipe 100 year old on who knows what # boiler total hack a piping only stuff the good is the original piping on parts of the system bout 45 ft the rest is knuckle headed most of the traps have never been touched can’t tell after over a 1 hr firing what’s good what’s bad because the mains don’t get that hot being there’s no insulation n the boiler is not even close to manafactures specs aside from all the great stuff how about the original thought. Peace n good luck clammy