Steam system experts

Pin

I have been dealing with the banging noise in the pipe for the past year and have came here for answers. The pipe that bangs originally had a horizontal section in the basement, which was thought to be the problem. So that section was cut out and a diagonally sloped section was inserted. However, this does not solve the problem. Only one radiator is connected to this riser and it is sloped the right way. Still can't figure out where the noise is coming from.



One additional issue for my system is that the entire system is made up of copper pipes. From the other steam systems I've seen and from reading this forum, it seems like people are using cast iron pipes. Maybe the previous owner redid it and went cheap on the materials.



My question is, is it worth it for me to redo my whole entire system including the pipes? or should I just leave it as it is and just resolve the hammering issue? Is there a steam expert around the NYC area that can help?



I have an oil boiler and not many people wants to work on them. Please give me some expert advice.



Thanks!

nicholas bonham-carter

copper pipe + steam

you may have a rare iron fireman system, sensitive to over pressure. can you post pictures of:

boiler with pressure gauge and control.

steam piping coming out of boiler.

valves etc. on radiators, with mfg's marks.

here is a link to the steam balancing co of nyc:

[url=http://www.heatinghelp.com/files/posts/276/HPACGiffordLoop.pdf]http://www.heatinghelp.com/files/posts/276/HPACGiffordLoop.pdf

and also to one of the most experienced contributors here, based in nyc:

[url=http://www.heatinghelp.com/forum/profile/88699/JohnNY]http://www.heatinghelp.com/forum/profile/88699/JohnNY

nbc

Pin

Pictures

I have attached many pictures of my very old steam system. Let me know what you guys think.

nicholas bonham-carter

banging pipes

there should be insulation on all the steam pipes to prevent both heat loss and excessive condensation, before the steam gets to the radiators. this could be a contributing factor in the banging.

i would suggest getting a good low pressure gauge [gaugestore.com 0-3 psi] and putting it on the same pigtail, [AKA syphon loop] so you can be sure that the pressure is  as low as possible with that type of pressuretrol, which can overshoot. sometimes the pigtail can get plugged up, and therefore prevents the control from "feeling" the pressure.

the steam piping is different to say the least, and i do not see a hartford loop, which is usually required to be next to the boiler as part of the return. i will be interested to read others views on the piping.

i would verify the pressure first, and insulate the supply pipes [if only with fiberglass batts as a temporary fix].

can't remember now when the water-hammer occurs-end of cycle, or beginning, but "the lost art of steam heating" goes into the causes of each type, parts of which are on this site, in the resources.--nbc

Steamhead

Also check

the burner's firing rate- if it's too high, the fast-moving steam can bang.



Not sure what to make of all that copper. The problem with copper around the boiler is the soldered joints can break from expansion stress. Are there any leaks in that piping?



And I'll bet that reducing tee at the main vent causes some banging.

Charlie from wmass

I am not one to promote switching

But in this case I would think strongly about switching to a hotwater system. Scrap the existing system and sell off the rads. You can get quotes for a repipe and a new properly installed steam system. Not quite the time of year for that though it does give time to plan for the Spring and nurse this one until then.

Pin

How do I check the firing rate?

So far, there are no leaks from pipe except one which was on the first floor and it was fixed.



Wherever the banging is coming from, its got to be in the basement with all the horizontal sections correct??

Unknown

Problem Tee

Here's a visual of what Steamhead was talking about. Your tee, with the vent, collects condensate (water) and when the condensate builds to a certain amount it will surge into the smaller pipe causing "water hammer".  On steam systems reduction in pipe size should only be done  with an eccentric reducer (unfortunately I don't think they are available in copper at this large a size) or reduce the pipe on the downward plane (elbow facing downward) so it won't collect water.

Pin

reducer

If they don't make that size of eccentric reducer in copper, then I will have to reduce the pipe at the elbow sloped downward. That would mean that I need to lower my entire return line.



Does anyone know differently and could identify a place that actually sell the eccentric reducer?

Steamhead

What you'd need

since they don't make copper eccentric reducers, is a 2-stage reduction using 90° elbows. The steam main looks like 2-inch- use a 2x3/4" tee for the main vent, then a 2x1-1/2" or 2x1-1/4" reducing 90° elbow for the first part of the U-turn, then a second reducing 90° elbow for the second part of the u-turn that would take it down to the size of the return, which looks like 1". If you line these up properly, you can get enough pitch to avoid banging, but keep the return line at or near its present height.

Pin

This might be a weird question

but if its available, can I install a cast iron eccentric reducer onto a copper pipe?



If not, what do you guys think of the idea of replacing the entire return line with 2inch pipe so no need to worry about reducers? Will it be cost effective than doing the two stage reducing like steamhead suggested?



Thanks!

TonyS

You can make your own reducers

You just need a few tools. Use a copper sweat cap for the larger size and drill it off center the size of the pipe your reducing to so the bottoms of the pipe are equal height, then slide in a piece of copper tube and silver braze the joint with sil-phos. The joint will be stronger than the copper.

Unknown

Reducer Elbows

Steamhead's suggest of using two reducer elbows makes really good sense. You can get the reducer elbows etc  from Pex Supply on the internet if they aren't available locally. I checked and they carry all the parts that you would need and you can price out what your material costs would be to make the change.  You'd need a new tee, and the reducing elbows. Having someone cut the old parts out for you and sweat in the new parts in  should be quite simple. You'll need a pro to do this as sweating big copper fittings takes a lot of heat and they have the equipment and experience to do this.  While I haven't priced this out I would consider this the most viable and economic solution to the methods you were considering. Adding a cast iron eccentric reducer would take about the same amount of refitting plus you might have a problem with galvanic corrosion due to the use of dissimilar metals. As for replacing the return  this would be more expensive and I would suggest the any funds would be better spent upgrading  your near boiler piping. Will this definitely fix the "banging? Who knows?   Though the reducer piping you have now is a very strong suspect as to the cause.

Pin

Dimensions

Just to get an idea on how much room I have to work with. The measurement from the ground to the height of the pipe at the end of main is approx 78 inches +/- 2 inches due to unfinished basement floor. The height of the end of the return line just before it turns vertically downward is approx 74 inches +/- 2 inches. The water level viewed from the sight glass is approx 38 inches +/- 2 inches from the floor.



I read somewhere that Dimension A, which is height from the water level to the end of main line must be at least 28 inches? From my calculation, I have approx 40 inches of space measuring from the end of supply line and approx 36 inches of space measuring from the end of return line.



My question is, how low can I lower the return pipe without creating any problem? This answer is important since if I have a lot of room, maybe I can do the steep sloped two stage reducing elbow. If i don't have a lot of room, then maybe its best for me to just replace the entire return line with 2 inch pipe.



Thanks!

Pin

Follow up question

Can I use 2" x 1" x by 3/4" tee to do the reducing and cap off the 3/4" end??

Unknown

Fitting Shouldn't Pool Water!

What you are trying to do is avoid any fitting that, by design, causes water to "pool". (See attached drawing) 

The tee you wish to use may not look quite like the one in the drawing but if on inspection it has some sort of a "shoulder" that you think  would form a pool of condensate (water), it  isn't a suitable  replacement  and won't be an improvement on what you have now. Since eccentric reducers don't exist in that size for copper pipe, Steamhead's solution is a very viable "fix" for  your problem.

- Rod

Pin

What about the dimension question that I outlined above??

What about the dimension question that I outlined above??

Unknown

Elbow Orientation

I  read what you mentioned though I'm a bit confused and thinking that we maybe on slightly different thought tracks. In Steamhead's suggested configuration,  the direction orientation of the elbows would be very close to what you have now,just different fittings. (The elbows aren't turned straight down if that was what you were thinking)  The idea is that the two reducer elbows have a far `milder "shoulder" than what you have now with the reducer on the end of the tee. The thought is to just cut the two pipes and add a new tee and the elbows to join the main and return . The main and return would be in exactly the same plane /height as they are now. Since you have to fit a new tee anyway, you might want to move it a bit back up the main to keep the vent dryer and away from the end elbows.

- Rod

Pin

Sorry for the confusion

Let me clarify. I am using steamhead's suggestion to do the two stage reducer. But I am curious to find out whether I can create a steeper slope during the elbow turn by lowering the entire return line? If I can do this, how low can I lower it in order for the system to still function smoothly?



I included a rough sketch of what I am proposing.

JN

I'm a noob to this but...

I think you want your return to have a slope of 1" over 10 ft and you need to make sure that where your dry return drops into your wet return that a the point where it drops the return line is 28" above the water line of your boiler. Am I making sense?

TonyS

Try this

Remove the concentric reducer on the T, make this simple fitting and reinstall. A/C installers make fittings like this all the time on systems that run at a little higher pressures. 

Steamhead

Pretty much

but on a parallel-flow main (dry returns are included) you only need to slope 1" in 20 feet.