Requesting Help to Understand and Maintain 2-pipe system

Chris_83

Hello,

I have been a lurker here for several years, and have learned much about steam heating systems (thanks to all who post here!).  I would like to learn more about my particular system so that I can better maintain it for both efficiency and longevity.



My house was constructed in 1937; it is a 2-story, 4-bedroom colonial located in lower Westchester County NY.  There is a basement under half the house and a crawl space under the other half.  I am the third owner, and purchased the house in 2001.  The previous owner installed the current boiler in 1985.  It is a Peerless JOT-5W which provides steam heat and domestic hot water.  The only vents I have located are in the crawl space, on the steam return line.  The oil tank is located outdoors, underground.



So, my first questions would be: What can you tell me about the system in general, from the pictures (or more info if you need it)?  Should there be more vents and where would they be located?  How can I test/remove/replace steam traps at the radiators?  What inspection, cleaning and maintenance should be done, other than yearly "cleaning" (burner and firebox) done by our oil company?

Rod

2 Pipe Steam

Hi Chris- Let me ask you a few questions to start off . Do you have any of Dan’s books on steam heating? If not I would highly suggest you get “The Lost Art of Steam Heating” and “We Got Steam Heat!” They are both available in the Shop section of this website. These books are written so someone new to steam can understand them and they will be a great help to you and save you a lot of money. They also really help if you ask a question we can then refer you to a specific page where Dan has explained a concept far better than we would ever hope to do.

Question about your system:

1. How well is your system working now?

2. What problems are you having with your system?

3. What is the maximum pressure your system runs?



On steam systems there are several areas to consider. One of these areas is the boiler piping.

From what I can see you have some issues here. I drew up a quick sketch of what I was able to make out from the different pictures you posted. Does the sketch portray the positions of the piping connectins to the header properly? In the sketch I labeled coming off the equalizer “Pipe “C” . Where does Pipe “C” go?



Photos- When you take photos take them from different angles around the boiler and from farther back so they include as much of the piping as possible. This allows us to trace the piping to see where it is attached othe boiler and to where it leads. If we need to see detail we can zoom in.



Another area we’ll consider is how the steam mains end.  One type ends with a pipe that connects the end of the Steam Main to the Return Main. This connecting pipe has to have a trap of some kind which allows water and cold air to pass through but doesn’t allow steam to pass through.  On this type there is No main vent on the Steam Main but her will be a main vent on the Return Main.  On  different type of configuration , the steam main doesn’t connect to the Return Main and just has a drip pipe at the end which drops down into the Wet Return Pipe which is close to floor level. This type of Steam main needs to have a Main Vent placed just before it drops down to the Wet Return. It will also have a main vent of the Return Main. I’ve attached a drawing of both types of Steam Main configurations. Which type does your system have?

Once we have the Mains figured out we’ll go on to radiators and radiator traps. Let me know what questions you have and I’ll do my best to answer them.

- Rod

nicholas bonham-carter

2 pipe tuning

i second the suggestion for low pressure on your vapor system. 8 ounces max should be best, verified by a good low-pressure gauge controlled by a vaporstat.

make sure the air can get out with no restriction [low back pressure].

there are some pipes in the picture labeled "crawlspace". are those returns, and if so probably should only join up at floor level, well below the waterline.--nbc

Steamhead

This is an Arco Model K Vapor Orifice system!

which you can find in chapter 15 of "The Lost Art of Steam Heating". Lucky you.



We know it's a Model K because of that side-mounted hex cap on the radiator valve. That's where the orifice adjustment is. This system has no traps on the radiators, nor does it need them. The orifices keep the steam from reaching the return connections, if the pressure is kept properly low.



You should use a Vaporstat to control the boiler pressure, rather than the usual Pressuretrol. This system only needs about eight ounces of pressure at the boiler to run properly.



Where in Westchester County are you located?

Chris_83

Additional Information

Rod's drawing looks correct.  Pipe "C" goes to the only radiator located in the basement, which is on the other side of a cinder-block wall.  This radiator doesn't heat at all.  The previous owner had installed an auxiliary heater next to the radiator to provide heat in the basement (that aux. heater has been removed).



How can I figure out which Steam Main configuration I have?



The pressuretrol is adjusted to its lowest setting.  The 30-0-30 gauge shows a couple of pounds of pressure when it cuts out (can't read it too accurately).  Several minutes after the thermostat stops calling for heat, that gauge shows a couple of pounds of vacuum and you can hear the sound of water draining in the pipes.  I don't know if that is normal.



There is a radiator in one of the upstairs bedrooms that doesn't heat.  Perhaps a clogged orfice?  How would I check that?



The only repair call (other than the burner system) in the past 10 years was to clean a clogged pigtail at the pressuretrol.



I flush the lwco regularly during the heating season, and for the first couple of weeks there is a lot of sludge that comes out.  I did try draining some water out of the boiler by opening the drain faucet, but nothing came out - I need to unclog it somehow.  Also, from what I have read on this website I should probably clean out the wet drain pipe that goes under the floor.



I will be purchasing Dan's two books.  I'm located in New Rochelle.



Thanks to all!

Rod

Arco Model K System

Hi Chris-

Thanks for posting the latest pictures. To find out what sort of mains you have, the best approach is to trace the returns back from the boiler.  I labeled the returns in two of your pictures. In the picture called  Return Piping Picture #1, there are two return pipes  labeled Return “P” and Return “M”.  To what labeled pipes in Return Piping Picture #2 do these two pipes connect?



When you follow each pipe through the wall in Picture #2, does each pipe have a main vent attached to it?  Do the return pipes attach to a larger pipe?  Let us know which pipes have vents and which are attached to larger pipes.



 These old systems, especially a Rolls Royce model like yours , were originally installed by steam experts, but over the years since have been “fixed” /modified by people that didn’t have a clue about how the system operated.  One of the first thing you have to do is figure out what “fixes”/modifications have been  have been made and remove the ones that are detrimental to the system.  

  On your system, one of the first things I noticed was your boiler piping isn’t configured properly. The order of the piping connected to the header is wrong as the pipes going from the header to the steam mains are between the risers going from the boiler to the header. In this configuration the steam streams collide, producing wet steam and also lowering efficiency. (See attached PDF)   If the system is performing  satisfactorily at the moment you may want to leave this and wait till the boiler is replaced to correct the piping  though since it is affecting efficiency it may be beneficial to do it sooner.  Typically the person replacing the boiler looks at the old one and connects the new one the same way which repeats the mistake made by some knucklehead years ago. “ The Blind leading the Blind!”  



Another problem I noticed is that the safety valve on your boiler doesn’t have an exhaust pipe. (See attached picture)   This directs the escaping steam in a direction where it won’t do any harm. As it is now, someone near the boiler might get burned by escaping steam. Safety valves rarely activate though if you are ever near on that does it is an experience you won’t forget!



Let us know where the returns lead and which ones have main vents on them. As you are tracing out the piping it will be a great help to you if you draw up a diagram of your system. This will help you understand it better and also be a helpful guide to any one working on the system.

- Rod 

Chris_83

Return Piping

Rod,



You are correct about the steam mains being configured improperly.



I never thought that my steam heating system was a Rolls Royce; always assumed that it was a basic Chevy.  Is it the radiators that make the system "above average", and are there special maintenance requirements?



The only connection in the basement between the pipes in Piping Picture #1 and Piping Picture #2 in your last post, is that Return 'X" in Picture 2 goes under the floor and joins the Wet Return in Picture 1.  Return "P" comes down through the ceiling from the first floor.  Return "M" is connected to the steam radiator on the other side of the wall (as I mentioned before, that radiator doesn't heat up).



These pictures from the crawl space should explain the returns from Picture 2.  Please let me know if more reconnaissance is needed.



Thank you very much!



Chris

Rod

2 Pipe Steam

Hi Chris- Thanks for the pictures. Could you re post these last pictures again but without the labels? The pictures with labels were very helpful. It's just that I need to relabel/name some pipes and I'm afraid it might be too confusing with so many labels!

I've attached one of the earlier pictures you posted. What I'm wondering - is the floor level that same as the boiler?  If so, how far up the wall/returns is the height equal to the height of the boiler's waterline? The blue dotted line is just for reference and means nothing. How far above or below the blue dotted line would the boiler's water line be.

I'm beginning to get an idea of how your system is configured. Doing it on this forum is sort of like trying to figure out a jigsaw puzzle from just a looking at a few pieces.



Orifice Systems- Due to the expense, adjustable orifice radiators are fairly rare. The adjustable orifice allows you to meter just enough steam flow into the radiator to fill the radiator needs. If the radiator turns out to be too large for the room, making the room too hot even on the coldest days, the orifice can be adjusted to so the radiator gets the correct amount of steam to heat the room.  This saves fuel!

You can also do this with orifice plates but it is much easier to do it with adjustable orifices that to change orifice plates. (Attached below is an article on orifice plates)



The big difference is that with a 2 pipe system you can throttle down the intake valve on the radiator to adjust the heat. It's possible to do this as there is a separate inlet for the steam and a separate outlet for the condensate,  On a 1 pipe system since the single pipe is used for steam to enter the radiator and condensate to leave the radiator, you can't throttle the valve down as it must remain fully open otherwise the steam stream entering the radiator and the condensate leaving will collide in the narrowed valve opening and cause problems. Thus having a 2 pipe system is a big improvement over the 1 Pipe system, orifices are even better and adjustable orifices even better than that!  2 pipe systems also allow a lot more fine "tuning - tweaking" than the 1 pipe system.

- Rod

Chris_83

More Info

Rod,



Yes, it is the same floor level.  The boiler sits on 5" high concrete blocks.  The water line (center of the glass sight tube) is 36" above the floor.  I marked this level on the photo.  The center of the close nipple of the Hartford Loop is 27" above the floor. 



Thanks,

Chris

Rod

Returns

Hi Chris-

    I think I’m slowly getting your system figured out. I’ve attached two reworked photos with some questions.  What we’re trying to do is to identify is the four drip lines (returns).  One return (drip) pipe each from Steam Main “A” and Return Main “A” and one pipe each from Steam Main “B” and Return Main “B”.  

   What designates the Steam Main “A” & “B” is their attachment to Risers “A” and Riser “B” in the Boiler Piping Drawing.  I see you have combined gauge on your boiler. Does it ever register vacuum and if so how much?  Also are there any make and model numbers on the two main vents?

- Rod

Chris_83

Info on Returns

Rod,



Here is additional information from this morning's recon mission into the crawl space:



Q1: That return pipe goes straight up - most likely a return from the second floor (Return from Main B or Steam B?).



Q2, Q3, Q4:  Those two pipes go up about two feet and then go through the wall on the left in those photos.  That would take them underneath the part of the first floor that has a basement underneath it, instead of a crawl space (living room).  The Q3 return pipe connects to the return main, which is behind the steam main in the photos.  That steam main connects to Steam Riser A. 



Return "P" is still a mystery.  There is another return that comes down through the ceiling along the same wall as "P".  That return is piped across the ceiling of the utility room and becomes the return pipe (A) underneath the crawl space.



The gauge on the furnace does register a couple psi of vacuum, after the thermostat stops calling for heat and things cool down for a few minutes.  There is also a gurgling sound of water in the pipes.  I know that there is a vacuum because if I open the LWCO drain valve during that time, air is sucked into the boiler through that drain.



The vent on the left in the photos is a Hoffman Main Vent Vacuum Valve #76.  The vent on the right is an American Radiator Co. Ideal Vacuum Vent #822.



I will try making a diagram of the system, starting with the boiler and pipes that you have helped me identify.  I don't have time to do that right now but I will draw and post it when I get a chance. 



Thanks again,

Chris

Chris_83

Drawing

Here is my first attempt at drawing a diagram of the piping at the boiler.  I tried to label the pipes to match the photos and discussion above.  I couldn't find any "how to diagram your system" posts or guides, so the colors and labels are not "standard" in any way.



Thanks,

Chris



Note: the site won't let me upload a pdf file so am attaching a rather poor quality jpeg instead...sorry...

Duff

hey Rod !

Hi Rod, I was wondering how your able to edit the pics sent to you and insert labels and symbols. I myself  have to send pics to request help for one of the topic rooms and was wondering how you do the voodoo that you do? Still learning,                        

Duff

Rod

Photo / Drawing Software

Hi Duff-

   The program I use is by Corel   http://www.corel.com/corel/ and is called PaintShop Pro X5  While its main use is for photo editing, it also has a lot of very good drawing tools.

- Rod

Chris_83

Diagram

Dang!  Still can't upload pdf file...

Chris_83

Better Drawing

I finally have a better jpeg of my first attempt at making a diagram of the boiler room.  Would appreciate input from this board as to how to make a better drawing.



Update:  still having problems uploading to this site.



Drawing is here  http://i53.tinypic.com/sv6ezp.jpg 



Thanks!!!