What main vents to use? Return vents?

Eric Scheidler

My steam main is about 67' and has no vents. It's an unusual main—it branches off from the header in two directions which meet, making one big loop. Read all about it <a href="http://forums.invision.net/Thread.cfm?CFApp=2&Thread_ID=29755&un=6e3yor">here</a>.

Here's a pretty accurate drawing of the main, with pipe widths indicated:

<img src="http://squarezero.org/images/steam10.jpg" />

The pipes are all pitched downward to the spot indicated with a star, which is where a drip ought to be. At or near that spot I'd like to add a vent. Or possibly I should add it at the other spot marked "plug," which happens to be just about the last spot to get hot when the boiler's firing. Or both.

There are about 6' of pipe from the boiler to the main loop. From that spot to the star is 19' going counter-clockwise and 43' going clockwise.

Going clockwise, the low point is about 24' from the header, most of which is 2 1/4" pipe; going counter-clockwise.

I need to know what type of vent to use here. Also, there are two sets of returns (not pictured) which more or less run alongside the main, and which are vented above the boiler. Here's a photo:

<img src="http://squarezero.org/images/steam11.jpg" />

I want to replace these vents. I've felt a little air coming from one of them, but the other, nothing. What vents should I use here?

I'd also apprecaite feedback on my plan to add a drip, described <a href="http://forums.invision.net/Thread.cfm?CFApp=2&Thread_ID=29755&un=6e3yor#Message198335">here</a>.

Eric Scheidler

Replacement for Dole No. 5 and Dole No. 6B?

Here's a close up of those vents:





The small print on the Dole No. 5 reads, "Quick vent float air valve," followed by the patent numbers and "Dole Valve Co., Morton Grove, Ill, USA."

The small pring o the Dole No. 6B reads, "Vacuum valve," followed by the parent numbers and "Dole Valve Co., Chicago, Ill, USA."

The 6B looks a little rustier than the other, but the could possibly be the same age.

Please advise which vents I should replace these with.

Also: does this printing on the 6B mean that I've got myself a vacuum system? If so, what does that mean vis-a-vis adding drips, main vents, rad traps, pressuretrol vs. vaporstat, etc.?

Steamhead (in transit)

For the mains

a Gorton #1 on the short one and a Gorton #2 on the long one should work fine.

How much radiation is on this system? That will give us an idea of how much air is coming at those dry return vents. No, you don't need vacuum vents on this system.

Eric Scheidler

I haven't calculated EDR figures yet, but maybe this description of my 8 radiators will be sufficient.

Four of them are 38" tall 3-column type:

1. 23" long, 9 segments

2. 19" long, 7 segments

3. 12" long, 5 segments

4. 20" long, 8 segments


Two are shorter 3-column type, 27" tall:

5. 46" long, 18 segments

6. 28" long, 11 segments


One of them is a 5-pipe type:

7. 16" tall, 58" long, 23 segments

And one is this monster:

8. 19" tall, 69" long, 23 segments



Here's a closeup of the valve, which looks original to me (based purely on intuition):



Says "Hammond" on the side. Here's another intersting valve knob, from radiator #3:



Says "Milwaukee Valve Co. on top." Only two other radiators have knobs (the rest are missing), these less interesting Hammonds:



Well -- That's all the radiator porn I've got for now. I hope the info on the radiators will be sufficient to recommend vents for the returns.

Thanks for all the help.