is this a vapor system and what do i have to know...

dobro23

sorry if this has already been discussed and i have missed it but I am replacing a boiler this week that is a bit unusual compared to others in the area. i believe it may have originally been a vapor system based on the piping layout, valves and fittings, etc. i am attaching a few ( blurry) pics just to see what you guys think and if there is anything i need to pay special attention to. a few of my immediate concerns are:
1. what is this fitting on the larger of the 2 returns that seems to have a vent on it? do i need to keep it or can it just be replaced with a regular main line vent or do i just plug it?
2. do i need main line vents on the end of the SUPPLY pipes to the radiators?
3. do I need a main line vent on both of the returns as they come back to the boiler?
4. am i correct in assuming that the check valve that is on one of the returns prior to the hartford loop should be removed?
5. do i need a vaporstat specifically or will a pressuretrol work if the pressure setting is kept low?
6. is standard near boiler piping acceptable here (ie, dim A, dropped header, equalizer, hartford loop etc)

I can provide better pics tomorrow if necessary.

dobro23

and also, how do i set the valves in the individual radiators? I assume i need to match them to the amount that is actually condensing in the radiator? How ?

JUGHNE

I am sure more pictures will be wanted. What is the name written on the handle of the rad valve? Are those special 90 connections on the lower rad cond return? Is there a vent pipe sticking into the chimney? What is the printing on the trap/vent/crossover device in the basement? I can't tell you anything other than ask questions.....but someone will recognize this system....I would guess a vapor type of some sort.

Do you recognize the fire extinguisher in your photo #3?
The large ice cream cone looking device with the red ball on top in the white metal holder....it usually has a spring loaded firing pin in the bottom to be activated by the melting of the lead link, just like a sprinkler head. Legend has it that this contains a fluid that will displace the oxygen enough to put out a fire and perhaps suffocate anyone in the room.....maybe carbon tetrachloride, not sure, some people here probably know more.
Anyway, use caution around it or even move it away.

New England SteamWorks

dobro23 said:

I am replacing a boiler this week that is a bit unusual compared to others in the area.

New England SteamWorks

Hopefully, you found your contractor here.

Otherwise, proceed with extreme caution.

Steamhead

Some sort of Vapor system for sure. The device with the vent is probably an air trap, and the vent probably has a vacuum check in it, though I don't think I've ever seen one that looks like that. I'm very interested to see who made them.

Where is this job located?

KC_Jones

dobro23 said:

I am replacing a boiler this week that is a bit unusual compared to others in the area.

Are you the contractor or the homeowner?

dobro23

I am the contractor. I guess i should have mentioned that!

Jamie Hall

Almost surely a vapour system, and I'd be willing to bet that there is some sort of gizmo in what looks like the innocent elbow at the outlet of the radiators.

We will know more if you can get some names, but here are some thoughts -- and questions.

On that fire extinguisher thingy. Haven't seen one in years -- except in the place I care for. The glass bulb is exceedingly fragile, and meant to be. The liquid is carbon tetrachloride -- good call, @JUGHNE -- and it is a hazardous substance, but it will put out a fuel fire right now. Don't breathe it, and try not to breathe the fumes if it gets onto a fire.

On the vapourstat -- I'm pretty sure you will need one; unless I miss my guess, that system will work best at 12 ounces per square inch or less.

You do need vents on the dry returns; that is how the radiators are vented. They can be clustered at the boiler, where the dry returns drop.

The check valve has to go. It was probably a kludge because of excessive boiler pressure.

You may or may not need, or even want, vents on the steam mains. If you go to the ends of the steam mains, is there a trap arranged to connect the end of the steam main with the dry return? If there is, that is sufficient for a vent for the steam main (provided you have those vents on the dry returns!). In some systems, it is necessary that there not be vents on the steam mains. The presence or absence of the crossover traps mentioned above is your clue for that.

You can control each radiator with its valve, but before you start playing with them make sure that your pressure is low and that you have operating crossover traps or main/dry return venting. It is possible that they may be pretty close to right, and it would be a shame to mess them up.

JUGHNE

Jamie, we had those extinguishers in the movie projector booth I worked in, they were there from the 1950's or earlier. Before the days of safety film there was nitrate film which burned like gas. Someone told me that if they ever broke to run away like hell.

dobro23

Thanks Jamie. I will know more tomorrow when i check it out for myself. I'm going by what our salesman told me. but he did make mention that the "trap/vent" thing was the only strange device. he did not notice any traps, or vents anywhere else in the system. and the device is only on 1 of the returns. I will take better pics tomorrow.

Steamhead

Dobro23 sent me some pics- this is a Thermal System, which appears on page 267 of Lost Art.