\"Strange\" main vent

Nelson R. Pardee

I'm trying to help my sister with their probably 80 year old single pipe steam system. It does not bang, nor exhibit other nasty symptoms. The most puzzling problem is I can't see any normal main vents. There are 3 10-12 inch "things" sticking up from the steam piping: one is just above where the return goes back in to the boiler, and the other two are about 15 feet back on 2 different branches of the piping. I attached a picture, or here it is on the web. http://web.syr.edu/~nrpardee/

The other problem is very uneven heat throughout the house, and yes, the radiators get evenly hot pretty much when they should. Having read "We Got Steam Heat", it looks like some TRV valves are in order. I'd appreciate any words of wisdom on selecting/buying them. It looks like it's a 3 part deal:
- valve
- temp control
- air vent (if I had straight shank ones it looks like I could use the existing ones- or can I use the existing angled ones too if I properly orient the valve?)

And- one room's very cold- it's about 6 x 15, 3 insulated outside walls full of windows (they are brand new energy star double panes). The radiator is a 7 section 40" or so high, and it gets hot!!! I'm guessing it just isn't big enough. We did try blowing a fan at it, and the room warmed up nicely- but then when the heat shuts off, it cools down quickly.

Dave Meers

strange indeed

Hi Nelson,

Thanks for the pics of the "vent". I have not seen one in person or in old literature. I suspect that the piping acts as an air chamber and some type of vent, possibly like a Hoffman 500 (a disc type vent normally used on water but rated for steam) is located on the side.

A couple of questions, do you hear air escaping from these devices? Can you get more of a close-up or description of the two tappings/fittings on the side?

The radiator in the cold room could very well be too small. Have a heat loss calculated and compare it to the output of the installed radiator.

You have to use straight shant vents with most brands of TRV's. Don't try to short cut that step. We sell the Danfoss brand at our supply house and they work very well. What city do you live in?

Best regards, Pat

DanHolohan

What are

its dimensions?

Nelson R. Pardee

Strange main \"vent\"

Nelson R. Pardee

Strange main \"vent\"

Thanks much, Pat and Dan, for your responses.

I have posted 5 more photos at http://web.syr.edu/~nrpardee. I'm using my palm to take the pics, so if better detail would help I'll trot out my "real" camera. These "vents" are screwed onto a short nipple. They are 6 1/8" tall by 1" diameter (diameter is for the body, not the rings or screws). The top is closed, and the closure is part of the casting or forging, it's not a cap. The screws have different heads, and the same types of screws are used on all three of these. I can neither feel nor hear air escaping anywhere when the burner is on. I and my sister and brother in law have looked but see nothing "sticking" up from any pipes other than these (seen nothing sticking out the side either).

I checked the pressuretrol, and it's set to 1 pound and 1.5 pounds (these appear to be the lowest setting it's intended to have). Having read "We Got Steam Heat" I think this is good. I could try to reset to .5 pound, but the scale doesn't appear to be designed for it- it's even above 1 pound, but the gap between 0 & 1 is small.

I'm in Syracuse NY.

gerry gill

hold some smoke by it,

like from a blown out candle or such, to see where the air exhausts from it....carbon post air vent perhaps? what do you guys think?

DanHolohan

These are

Breckenridge air vents, invented by Moses Breckenridge, an employee of the H.B. Smith Company, in 1868. They are carbon-post vents, and they're the oldest around. We have one in our collection. Congratulations!

Nelson R. Pardee

Breckenridge Air Vents

Dan, thank you for clearing up the mystery. The house dates from 1910-1930, no one seems sure. I'm wondering if these vents were scavenged from older system?

If you have time, I wondered if there is any maintenance on these vents? How they work?

Thanks again.

gerry gill

hey Dan,

do you think it was patented? is there a date on it? ;-)

DanHolohan

I was wrong about the carbon post.

It's a brass element. Here's some words and pictures about it (and other good stuff) from 1928. The source is Practical Steam, Hot Water and Vapor Heating and Ventilation by Alfred G. King.

DanHolohan

It was actually

an expanding brass element, not a carbon post. Here's the reference.

DanHolohan

Mine is so old

that I can't read a date or any other markings. Mostly rust, Gerry.

gerry gill

cool stuff Dan

neat-thanks for posting it.

Nelson R. Pardee

Strange main \"vent\" - yet another look

Wow- the "Wall" has sure been useful!

They are in pretty good external shape- appear to have black paint that is largely intact. I can see no writing on them.

Dan, the text you posted was real interesting. I wish they had included a diagram of the Breckenridge vent internals like they did of the others.

I took a close look at the two "screws"- the lower one appears to be a real screw with threads. The upper one (at least the visible part) is smooth, and tapers in toward the vent. I tried pushing on it by hand, but nothing happens. I wonder if this is frozen shut, and if so, what I should do (if anything). I'm also guessing that the bottom screw anchors the mechanism?

Mike Cascio

What book is that from?

Hi Dan,

I read through the attachment that you put on this post. What book is that from?

Thank you,
Michael J. Cascio

DanHolohan

The book is

500 Plain Answers to Direct Questions on Steam, Hot Water, Vapor and Vacuum Heating by Alfred G. King