2 pipe Steam

Jim Robinson_2

Do I leave this kidney shaped air vent? On this 2 pipe steam trapped system I have to replace the boiler and I am thinking it is here for a reason but the guy who installed it is dead!

Danny Scully

This is going to sound harsh Jim, but if you don't know what that is, you probably shouldn't be replacing the boiler. You are correct, however, it is there for a reason. Do you have a copy of the Lost Art?

ChrisJ

I've got a feeling this isn't going to end well for the system.

What are your plans for the rest of the piping? What size boiler are you using?

@Steamhead

JUGHNE

This is something different......vapor/vacuum etc....someone here will probably tell you.

How has it been working with the existing piping (not good BTY) on the boiler?

The old boiler must be leaking?

New England SteamWorks

It's a Dunham 2203 Air Eliminator. I think it looks like a heart, so when I rebuild them I paint them red. Rebuilding one this very afternoon. It stays.

Steamhead

What @New England SteamWorks said.

In this system, the radiators do not have air vents on them. Air exits the radiators through the traps, travels through the dry (overhead) returns and goes out through that vent. Without the vent, the system won't heat well, if it heats at all. There should also be radiator traps piped between the ends of the steam mains and the dry returns. These route the air from the steam mains quickly into the dry returns and out the vent. If these are leaking or stuck shut, the system won't heat well.

And I hope you're not going to re-use the existing steam piping around the boiler. It was wrong from the get-go. What boiler are you going to install?

Gordo

This is a video of Warren Webster's smaller version of the Dunham air eliminator.
https://www.youtube.com/watch?v=YO7_65-uWzw

JohnNY

@Gordo, do you think that can be replaced with some creative piping terminating to a Hoffman 79? It seems like the functions are similar.

Steamhead

JohnNY said:

@Gordo, do you think that can be replaced with some creative piping terminating to a Hoffman 79? It seems like the functions are similar.

Hoffman #79? That's a hot-water vent:

http://bellgossett.com/steam-specialties/water-vents-model-77-78-79/

You need a vent that can close against steam if, for example, a trap fails open and fills the dry return with steam.

One Gorton #2 is the minimum here. The only vents Hoffman ever made that were big enough for a system like this were the #10 non-vacuum and #11 vacuum vents, and those went out of production sometime around 1930.

Since this is on a "B" dimension rather than an "A" dimension, I would not use a Big Mouth. You need a vent with a float so the vent won't discharge water if the pressure gets too high.

New England SteamWorks

Beating once again.