Trying to learn

mdangelo

New home buyer and trying to learn all I can about my steam system and I have a ton of questions but I'll try and start with the simple. I've read through we got steam heat and the first quarter of lost art of steam heating and haven't been able to find my particular type of radiator (though I may have missed it) and why my one pipe system has several radiators with two supply valves. I presumed the larger pipe was for steam and the smaller was for condensate to drain. The only thing in common that I've noticed is that they tend to have more sections/taller sections than my other radiators. I also don't see anything like a screw/push nipple or tie rod in the above radiator. It appears the rods screw into the base instead but that was just an assumption. Thanks for the help!

Jamie Hall

The very earliest two pipe systems had no traps or orifices, and in a very real way were one pipe systems, only with two pipes (!) -- one of which was intended primarily for condensate to drain, the intended primarily for steam feed. In fact, in most of them steam feeds through both pipes -- and condensate tends to drain through both. They need air vents -- which you have -- just like a regular one pipe system.

The radiators are a tube type, and don't have tie rods -- again, a somewhat earlier design.

BobC

One of your pictures shows the air vent is a Heatimer Varivent, those can vent extremely fast unless set way down low.

Does the system heat quietly and evenly?

Bob

mdangelo

Jamie - I presumed my system was a one pipe design because half of my radiators have the setup in the picture below. Is it possible to have a mix of the two?

Bob - I replaced the air vent that was on the radiator which is included in the picture below on one of my other radiators. It was one of two varieties of air vents on the radiators in the home. The other type was a Hofmann (sp?) brand. I have these new varivalves opened all the way in an effort to do exactly what you asked but I've been only mildly successful in getting heat evenly throughout the system. Occasional, and relatively mild water hammer after it gets warmed up. Maybe 4-6 quiet bangs. I haven't had a chance to see where it comes from and I don't even know if it happens every time. I thought it was coming from the equalizer as it joins the loop (as if I know what I'm talking about!) or its coming from one of the last risers off the main (or both).

Steamhead

The rads in your first series of pics are pipe rads. Each pipe is attached to the base, there are no push or screw nipples. I didn't see a name in the pics, is there anything on the base?

This group of rads are column rads. There is a rod holding the tops of the sections together but I don't see one at the bottom. It's either hidden inside the rad, or there are screw nipples along the bottom.

BobC

In general you want to vent the mains quickly and the radiators slowly, that usually makes it easier to balance things. If you vent a radiator too fast the steam can just shoot across without actually filling the radiator. Ideally each radiator should be vented proportionately to the volume of air in the radiator and the piping connecting it to the steam main.

What kind of venting do you have in the cellar?

It also looks like your equalizer is coming off the boiler header before the takeoffs to the three mains and that may cause problems.

Bob

mdangelo

Steam head - My pipe radiator has no name whatsoever on it. The only writing is on the caps to the pipes but it just says: PAT JAN 12 AUG 17 1875 as far as I can tell.

Bob - I attached a picture of the basement near boiler piping and the equalizer. Any thoughts? My two main air vents are at the end of the return, i think. Those new varivalves on the radiator didn't seem to do much and the old ones I took off appeared to have a fast/slow dial on top anyway so I'm not sure they were the issue.

Jamie Hall

It is indeed possible to have both one pipe and two pipe connections on the same system. Not the best idea in the world, but it works OK. It can be a little tricky to balance.

Which brings up vents... in general, if one is having trouble getting even heat, the way to approach the problem (doesn't always work) is counterintuitive: don't try to speed up the colder radiators. Try to slow down the hotter, faster ones. That, plus trying to make sure that steam gets to all the runouts in reasonably equal lengths of time, which involves main venting, is the way to do it.

BobC

i take what I said about your equalizer back, I must have been thinking of another post on the site. However those main vents are only rated for 0.11 CFM and that may be too slow. My main is only 15 ft and I have 6X what you have.

How long is each steam main and what size pipe is it? Also I only see a single takeoff from the boiler header, how does it feed both steam mains?

Bob

mdangelo

Longer main is 56 feet and 3 inch pipe and the shorter is 31 feet with 3 inch as well. I've included a picture of the main air vents as well.
Both Legend Valve T-65 max pressure 10psi.

The main problem are the last two runs off the log main. The short main radiators seem to get warm 20 minutes before the radiators half way out on my longer main.

mdangelo

I forgot to include a picture of he header feeding the mains

Steamhead

That might be a Reed radiator- in Dan's book "The Lost Art of Steam Heating", he says John Reed introduced his rad in 1878.

Those cute little Legend vents are part of your problem. No wonder the rads toward the ends of the mains heat slowly. I'd start with one Gorton #2 on the short main and two of them on the long main, and adjust from there. The Gorton #2 is the largest main vent available.

Double D

Are you sure your mains are 3"? A 3" iron pipe will have a circumference of 11", a 2-1/2" pipe will be 9" and a 2" pipe will be 7-1/2".

mdangelo

Sorry, you're right. It's a 2 1/2 inch. Was trying to meausre the circference with my tape measure and did a poor job.

BobC

If you want to achieve a balanced system the long main has to have almost twice the venting that the shorter main does. Your timings seem to prove that point everything else being equal.

I would install 2ea Gorton #2's on the long main and 1ea #2 on the short main. The Gorton #2 is a large vent (7") and it has a 1/2" fitting so you will need an adapter for your 3/4" fitting.

They are not cheap, if you want to prove the point at a lower price point use one maid o mist #1 on the sort main and 2 maid o mists on the the long main. That won't be optimal but one maid o mist #1 will vent 3X faster than what you have now.

Bob

mdangelo

Thanks! I finally feeling like I'm getting somewhere. I'll probably go straight to the Groton vents as I can't see a downside. Can you have too much main venting?

BobC

You can never have to much main venting but if you pay for more than you really need it just costs you more than it should in an ideal world.

There is some disagreement as to the amount of main venting we should have, but it is just a one time expense. The gorton # 2 vents at 1.1 cfm while a Maid or Mist #1 (or the Gorton #1) vents at 0.33 cfm. Keep in mind the body of the #2 is about 6" in diameter so make sure you have room to thread it in place.

Bob