In-airid steam vent

chestyp74

Have any one if you fine people cone across a steam rad vent such as this?

Steamhead

Many times! Welcome to the World of Steam.

Erin Holohan Haskell

Here are some articles about the In-Air-Rid vent:

https://heatinghelp.com/systems-help-center/in-appreciation-of-steam-radiator-vents/

https://heatinghelp.com/blog/doctor-bobs-radiator/

And here's the patent: https://heatinghelp.com/heating-museum/in-air-rid-vent-patent/

JUGHNE

I thought the vent hole in those was a paper clip size.
This one looks reamed out....or not?

chestyp74

So I'm assuming that like all one pipe air vents, these need replacing every 10 years as well? Not 80 years. What is the vent rate on these, I'm assuming these aren't a one size fits all. This job has rads as big as 120 edr and as small as 27 edr. Very I'm even heat. End of mains are getting a make over as well. I want to remove them and put Hoffman 1a adjustable vents in to balance the system better.

chestyp74

Yes the hole does appear to be larger than a paper clip. This pic is on a road with edr of 120. Is the their way of allowing to vent the rad faster by reaming the hole out?

nicholas bonham-carter

If they are letting the air out, and closing against steam, then they are still good, even though, they are really mounted in a higher position than a standard radiator vent.
What sort of main vents have you got?—NBC

Danny Scully

@nicholas bonham-carter, “The In-Air-Rid also has a spring loaded seat that seals the last radiator section from the next-to-last section. When steam enters the radiator from the bottom it rises to the top of the radiator because it's lighter than air. Once at the top, the steam wants to move horizontally across the top of the radiator and toward the vent. Without that spring-loaded seat, the steam would close the vent before most of the radiator was hot, but with it, the steam has to take a detour downward through that next-to-last radiator section, and then upward into the final section. This ensures that the radiator heats all the way across.” If you remove them @chestyp74, please send them all my way, free of charge of course. Consider it tuition

chestyp74

The EOM vent is the typical single vent that is plugged up. It takes steam 30 plus minutes to make its way around. I am bidding 5 new gorton main vents. I will attempt to remove those in-arid vents hot cold method. If the body is all brass I should be ok. If it's cast iron they may have to be cut out. Yes. If anyone wants one I will share. I have 9 to remove.

JUGHNE

I would just leave them if not leaking.
Add an air vent on the side in the normal location.

Are there plugged taps on the side of the rad.

AntB

I also have a 90+ year old house with a gas fired, steam-heat boiler with one-pipe radiators. I am not sure if these are In-Airid air vents, but I've not found any other air vents on any of the radiators in my home; and I, too, have a few very cold ones. I plan to call the Baltimore contractor for advice, but wanted to put it out there here as well. 2 pictures each, of 2 of my 10+ radiators

Thanks in advance

Steamhead

This looks like a Hoffman Vapor system. Call @The Steam Whisperer (Formerly Boilerpro) and he'll take good care of you.

AntB

Thanks @Steamhead - appreciate the input. Will call my local pro. Here is a pic of the main air vent (only one I've seen in the system) and the loop in the basement. Does this help?

mattmia2

I would recommend calling the peon we know has worked on Hoffman vapor systems before. Yours looks to be intact and someone who doesn't know how those systems work could really screw it up.

It is a 2 pipe system, your radiators vent through the return and through that Hoffman device on the return, they do not have radiator vents.

Jamie Hall

That does indeed appear to be a more or less intact Hoffman Equipped system, @AntB . Operates on very low pressure -- less than 7 ounces per square inch.

You state that you have "one-pipe radiators". I beg to differ, if those pictures are of your radiators. They are two pipe.

The probability of some idiot messing it up beyond recovery is substantial. Please, please call @The Steam Whisperer (Formerly Boilerpro) to work on it. If he is unavailable or you are out of the area, please please first get a copy of "The Lost Art of Steam Heating" and read it, in particular the section on your system. Then, if you hire someone to work on the system, ask him or her to explain what the purpose of the Hoffman Differential Loop you pictured is, and how it accomplishes that purpose (hint: the purpose is to limit the maximum pressure differential between the mains and the dry returns to between 7 and ounces per square inch). If they can't do that, show them the door.

Just to give you some starters.

There must be no, repeat no, vents on the system anywhere except where that one is located over that "loop" (Hoffman Differential Loop) in the basement. If you find others scattered around, whether on radiators or steam mains, they don't belong and they've got to go. Remove them and plug the holes.

The crossover traps must be present and functioning. If they've been removed, replace them. If they aren't functioning, repair or replace them.

The radiator traps must all be functioning, although if the valves on the radiators are set properly that isn't as critical if they are failed open. If they are failed closed, repair them.

If your boiler is not controlled by a vapoustat or other low pressure controller, it needs to be. The cutoff should be set to 6 ounces per square inch (and verified by a reliable low pressure gauge) and the cutio should be about 3 ounces.

Do it right and you will have one of the best, quietest, and most even heating systems made. Do it wrong, and you will have a mess.

AntB

Thanks Jamie,
I did have a conversation with @Steamhead, who told me many of the same things you did. I have been looking around all over the internet and had only found posts/forums, etc. about 1- or 2-pipe, steam or water boilers. Even most of my local contractors would ask that question with those - and only those - factors. Never about vapor. I will get Dan's book soon.

In the meantime, as noted by you and @Steamhead, @Steam Whisperer will be called soon. From the radiator, they look like one pipes, and last night when I found HeatingHelp.com, I thought I'd struck gold in learning about the In-Airid vents (and it's been fascinating reading on the history of boilers/heating), so I was up pretty late trying to take apart what I thought was an In-Airid vent in one of my existing (not in service) radiators in the basement. 24" pipe wrench and it wouldn't budge. I kept looking at the "vent" (plug) and saying, "this just doesn't look exactly the same," so I'm grateful to find you guys with so much knowledge and passion for this art.

I think I'm finally on the right track to solving the problems of cold radiators, water hammer, cold rooms, and probably more energy use than necessary in heating my home.

Thanks much!!

Jamie Hall

Glad you found our comments useful, @AntB ! And I can assure you that providing nothing really drastic has been done to your system @The Steam Whisperer (Formerly Boilerpro) will make all of the problems you mention vanish. And even if something drastic has been done -- it happens! -- he will be able to find it and correct it.

The Hoffman Equipped system is dismayingly simple, and like most vapour systems, when it's in full working order it's almost magic.

nickdu

Danny Scully said:

@nicholas bonham-carter, “The In-Air-Rid also has a spring loaded seat that seals the last radiator section from the next-to-last section. When steam enters the radiator from the bottom it rises to the top of the radiator because it's lighter than air. Once at the top, the steam wants to move horizontally across the top of the radiator and toward the vent. Without that spring-loaded seat, the steam would close the vent before most of the radiator was hot, but with it, the steam has to take a detour downward through that next-to-last radiator section, and then upward into the final section. This ensures that the radiator heats all the way across.”

I'm curious then, why not just always leave the top push nipple between the last two sections closed and use a regular vent? Wouldn't that produce similar results?