Converting Eddy Vacuum System

taskguy

Hello, I have inherited my parents historic home built in 1926. The steam heating system had not worked exactly right for the last 30 years but did work. Last year the boiler died and and a new Dunkirk PSB-8D boiler was delivered. My parents since passed away and we are now wanting to finish installation of the new boiler. I ordered The Lost Art of Steam Heating and have been studying diligently. It appears that the system was designed as a one-pipe, Eddy System due to the Eddy retarder vents installed on each radiator and piped into the basement. It also appears that over the years some of the required equipment for this type of system has been removed and/or modified by my father who repaired everything himself with help and advice from local experts. However, the home is in southern New Mexico and the availability of local steam experts has been non-existent for many years.  All height and dimension requirements are there to install as a traditional gravity return one-pipe system. There is 3" Riser & Header, 2 1/2" Mains, 1 1/2" wet return. 11 radiators 591 sq.ft. EDR.



My question is: Can this be done by installing traditional radiator vents, main vent, and proper return piping per MFG instructions and capping off the air returns from the old Eddy vents?

Steamhead

I wouldn't go that way

the piping was sized for the higher pressure differential the vacuum provided. You may experience steam distribution problems if you do that.



A small ejector, as used on the Moline system, might be the way to go. Or, a small vacuum pump.

taskguy

pipe sizing on Eddy System

I was concerned about pipe sizing myself. My longest main starts out at 3" and ends with 2 1/2. I calculated total sq ft of EDR at 452 for the entire run including 20% pickup factor for insulated Piping. Referencing Dan's book, his chart shows that 2 1/2" piping will service 635 sq ft.. In reading, I understood that they downsized piping when they started adding vacuum to two pipe systems. I believe this system is piped according to traditional one-pipe system requirements with the addition of eddy vents.



Of course I'm no where close to being well versed in all this but do need advice on how to Pipe in the new boiler. Has anyone updated one of these systems and if so a system schematic would be very helpful.

MDNLansing

Still looking for help?

Last spring I bought an old historic house with an original Eddy system designed from the start. I just recently learn of the fact that it is a true Eddy system and not a modification and have learned a tremendous amount about these systems in the last few weeks. I am currently restoring the Eddy components of my system that generate the large vacuum draw so I might be of some help here if you still need it. It really is a quite simple system, but the components are very specific and there are not alternates or replacements. It make the Eddy Vacuum system run properly, you really do need all the right pieces. Let me know if you're still working on this and I'll offer up what help I can.



http://books.google.com/books?id=mBpbAAAAYAAJ&q=eddy#v=snippet&q=eddy&f=false



This is a good start. Notice how the radiator vents aren't just simple 90 degree components with a plug port on them. They are designed to control the amount of air venting the radiator to the proper amount.