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2-pipe steam system air vents on dry return leaking water
Having trouble getting the water from the return lines back to the boiler. We changed some bad steam traps. Removed (2) F&T traps which were on dry returns (somebody had tried to master trap both sides of the house). Then realized someone had removed the dry return going back to the boiler room. We have vents on the steam mains (no problems working well). We also have vents on the dry returns before they drop in to the wet return (which come from the drips at the end of the steam mains. There are (2) steam mains going to each side of the house). Radiators all appear to be working well now, but a lot of water coming out of the vents at the end of dry returns before they drop in to the wet returns. I realized that someone had removed the dry returns going back to the boiler room. I have a 3lb pressure gauge on the boiler. Once the pressure hits between .5 and 1lb vents on the dry returns will start squirting water. I'm happy to reinstall the dry return back to the boiler room but don't fully understand how if I tie it into the wet returns before the hartford loop it will be any different then tying it in to the wet return 20-30ft away. I just want to make sure that if we do reinstall the dry return, it will solve the problem. I'm also thinking maybe we need condensate or boiler feed pumps. Looking for some advice
Boiler was replaced some time around 2005. I don't know when the dry returns were removed. Wet returns run on the floor back to the boiler room. Boiler is in a pit approximately 12" below the floor where the wet returns run. I can run the dry returns back to the boiler room and tie them in probably 12" lower then they're tied into the wet return right now. Just not sure that will make a difference. I know I have to have good quality main vents at the end of the dry returns. Boiler is also flooding and going off on low water at different times.
Just to recap: These are my possible options:
1. Install (2) boiler feed pumps: (1) at the end of each dry return and pump the water back to the boiler. This should definitely solve the problem.
2. Reinstall the (2) dry returns back to the boiler room and tie in before the hartford loop. Not 100% sure this will solve the problem but it's possible that the wet return pipe size is not large enough to bring all the condensate back from the returns as well as the condensate from the steam mains. That added to the fact that there will be no pressure in the dry return and there will be some pressure in the wet return could equate to the fact that we are not getting water from the dry returns back to the boiler. Instead it's squirting out of the vents on the dry returns. If I do run the dry returns back to the boiler, and it doesn't solve the problem. I may still end up having to install a condensate or a boiler feed pump. Another factor is, I don't know where the old water level on the old boiler was. This was all done before we got there. I will measure the B dimension later today and repost, but educated guess, it's approximately 36" maybe even less. I did also consider installing a vaporstat, but if I have water spitting out of the vents at .5lb I think I will need at least 1lb cut out to operate the system properly. Any advice greatly appreciated.