Help identifiying old steam device

heidleml

Here is a pic of a device on a two pipe system in Maryland. We are replacing existing boiler this week.

heidleml

Pic attached

Jamie Hall

@Steamhead will tell you exactly the name of the system -- but it's a vapour system, which means you want to have nice low pressure and a vapourstat control -- probably around 10 ounce cutout. It almost certainly has crossover traps at the ends of the steam mains connecting to the dry returns. Make sure those are working properly, and don't be tempted to put vents there. They don't belong there.

KC_Jones

To keep pressure low make sure you size it properly, this will be critical even more so than the Vaporstat control in my opinion. Also top notch near boiler piping.

Erin Holohan Haskell

That's a boiler return trap. You can find more about it in Chapter 15 of The Lost Art of Steam Heating.

And here is the original documentation for that Illinois Vapor Heating System: https://archive.org/details/IllinoisThermoModulatingSystemOfVaporHeatingIllinoisEngineeringCo._824 You'll find the return trap on page 17 with more info about its operation.

Steamhead

Jamie Hall said:

@Steamhead will tell you exactly the name of the system

I don't have to, 'cause @Erin Holohan Haskell nailed it.

Where in Maryland is this?

heidleml

@Erin Holohan Haskell Thank you so much for this amazing resource!!
@Steamhead Boiler replacement is in Harwood (southern Anne Arundel co.). I may have come across a service ticket of yours (All Steamed Up?) at another steam job in south county. Big house on the water, a plumbing company botched putting the steam system back together after the house caught fire. I couldn't have agreed more with your technical description of the situation on your ticket "FUBAR".

Steamhead

Oh yes, I remember that job. IIRC, there were issues as to who was going to pay for the repairs that needed to be resolved. That's the last I remember. Do you know what ultimately happened there?

SteamCoffee

The system you are asking about has had a couple great discussion from a few months back. The size on the unit iirc is for under 1000 edr. Vents under a 1/3 of an ounce, the acts as a vacuum vent to seal the system, and has some return capabilities if the return backs up. Super neat system. 2 things it needs most are 1)Absolutely crucial to have low pressure. 2)water in the unit to make the float work. If there is no plan to keep it, I would love to take it off your hands. Btw, the newer gasket means someone's been in there, hope it didn't get "improved"

heidleml

@Steamhead She payed for re-piping the majority of the pipes in the crawlspace. I spent a few days under there. There were a few places where pitch became an issue but everything turned out well for that wing of the house. Of course, most of her rad traps were also shot. We just replaced the boiler this winter. Ill attach a pic.

heidleml

@SteamCoffee The boiler we are replacing had a cracked section. It was only 4 years old. Some oil company installed and serviced and when I arrrived the power had been disconnected and boiler almost completely dismantled. I will say the vaporstat was set for 2 1/2 psi. Should I be installing the vaporstat with ozs for both t

SteamCoffee

I re-read the Illinois System manual...., it sold itself, like many other Systems of the time as a 3 in 1 function. A low resistance "open" system to quickly fill on cold start, a vacuum system when the fire was doused, then a limited boiler return system when the returns backed up. All of the functions are predicated on careful piping, low pressures and the ball float in the unit working. Without all those parameters met, it turns into a very heavy place to mount a vent on. It looks like someone has been inside the unit, judging by the red silicon gasket. I kinda doubt many installers would understand the nuances of the way it functions. Getting to know the system and getting it up and going would be great. Otherwise you may have to simplify it. Depends on the amount of time you want to devote to it. Good luck, to the right homeowner, it could be a real winner.

Fred

One would like to believe that it just leaked at the old gasket and that someone replaced that old gasket.

SteamCoffee

The take away is that 2 of 3 functions may not be needed. The return trap function is almost irrelevant if your b dimension and system pressure are squared away. It's a left over from the coal burning days where dampers couldn't always keep the coal from flaring up and spiking pressure. The vacuum function is nice, but not necessary. What's left is a 95lbs cast iron vent...a vent whose rate is unknown and again, probably happier in a slow steady vent/burn associated with coal. Btw I hope Fred is right. either way, let us know..