two pipe steam without traps and with a dry return

The Kid

A friend of mine asked me to take a look at a job that he would like to bid on. He asked me because it is a steam system. I said " sure" thinking i know a little someting about steam "I'll bring my book". The house is a six family with one steam boiler set up as a two pipe with a dry return. No traps on any of the returns and we where unable to get into any apartments that day, so not sure of if there are any traps on the radaitors, i'm thinking no, becuase i didnt see any on the dry returns, however seeing is believing so i can't assume. All the ends of the mains and dry returns have vents. If the radiators do not have traps and the returns are not directly piped into the wet return below the water line then there is that posiblity of the steam backing up into the radiator returns..Correct? WOW just had a vision...The main doesn't loop back and turn into a dry return... which would explain not needing a trap. the main runs out and at the end and there is a vent and a drip into the wet return. so the returns from the radiator have a seprate return loop and I now would guess that the radiators have traps....so with that i must make sure i have 30 inches of height for each pound of steam at the boiler and i should because the lowest trap would be in the first floor radiator....Is that right...?? am i making sense...haha....

Mad Dog

The rads probably have traps

but you really have to see it for yourself. Mad Dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Steamhead

You're on the right track

That's probably an old Vapor system. As with any system that uses a dry return, there has to be a way to stop steam from reaching the dry return.

As Dan says in chapter 15 of Lost Art, you can do this with traps, water seals (Broomell, VECO etc), check valves (Kriebel, Donnelly, Richardson, O-E etc) or orifices (Arco Model K, Thermal etc). Once you see the radiators you'll know what you're looking at.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"