1907 New York Building Restoration

EdSheridan

Hello all,

I am a builder currently restoring a 2.5 story home constructed between 1907-09 in Bronx, New York. The building was built as a single family home. It is heated by the original steam radiators and was converted from an original coal boiler to oil then to natural gas. The latest boiler is a Burnham Independence IN8.

I've tried to familiarize myself with the principles of steam heat before posting so I can formulate some educated questions and i've plowed through a number of articles, listened to Dan's seminars, and gotten dizzy looking at Gerry and Steve's "Balancing Steam Systems" venting capacity charts.

I'd like to resolve some of the problems i'm having and maximize the efficiency of the system. Here's what i'm dealing with and my proposed solution. Please weigh in if you think i'm off-track or have input toward resolution.

STEAM SYSTEM DESCRIPTION:
This is a one-pipe steam system with a total of 9 radiators, 8 of which are two column radiators and 1 decorative wide under-bench style 13" radiator.

There are 2 primary risers on each side of the building, an eastern riser (which is geographically closer to the boiler almost directly overhead, which branches at the 2nd floor to feed 4 of the 9 radiators) There is a two-pipe return system in the basement for condensate which is 1" and runs beneath the 2" mains. The oil to gas boiler conversion was done in 2016, but no balancing of the steam system was done, and there is no master venting on the main, risers or returns. Based on some historical construction forensics, we know there were at least 2 additional radiators which have been removed from the system. The buildings had uninsulated wall cavities, which have now been filled so the system is likely way oversized for heating needs but, is pretty inefficient at delivering balanced heat to the upper floors while the lower floors are warm.

PROBLEMS:
In the last week or so, I noticed that a substantial amount of water gurgling and spitting out of the air release valves on a two of the 2nd floor radiators which share a common riser, The water is of course dark iron oxide color and threatens the hardwood floors. I confirmed that the radiators both had drain pitch back toward the valves. I figured that the air valves (Hoffman 40's .042cfm @ 1oz) were clogged or broken so, without any real knowledge of venting capacity, I swapped the valves with new Gorton "C" (.27 @1oz.) which of course made the problem worse. then I switched them to Gorton No. 4 valves which reduced the problem -- but not resolved it entirely.

Continuing with a dangerous amount of knowledge on the subject, I then replaced all the 3rd floor radiator valves from Hoffman 40's to Gorton "D" vents. and the remaining 2nd floor radiators with Gorton C's in hopes that this would allow for more rapid displacement of air at the riser ends. In addition to replacing the air valves. I also flushed the boiler and cleaned out the return valve at the bottom of the Hartford loop which was clogged with debris, hoping that cleaning the dirty water might give me cleaner "dryer steam" This was of course pretty un-scientific guesswork, then I came across this website.

I'd like to diagnose what is causing the spitting of the radiators, and what I can do to fix this, and while im at it I figure I should try to optimize the balance and efficiency too.

ADDITIONAL OBSERVATIONS:
The primary pressuretrol of the boiler is set to 0.5psi, upon first firing, boiler comes on and functions normally until steam is produced - the header gets hot, but before any of the radiators on the upper floors are hot, the system shuts off and then immediately turns back on, you hear the roll-out and electric ignition system come on, and water boiling again, then shuts off again. After repeated on/off cycles too numerous to count, the radiators begin to get hot. and the system seems to run semi-normally.

From what I can tell, the near boiler piping was installed adequately, albeit without some of the expert appurtenances like a drop header etc. I do have the requisite minimum 24" of vertical rise before the header, and no mains or piping coming off the header between the two boiler outlet pipes. The boiler pipes are

Based on reading and listening to all of you -- My thinking is that the pressure is building up in the system because of insufficient main/riser venting, and is thus causing the pressuretrol to shut off the boiler at 0.5psi (8oz). The undisplayed air still in the mains is slowing the movement of steam to to radiators. But since there is no existing main vent, I plan to drill an tap a 3/4" hole into an abandoned nipple and cap which sticks out at the main

We have always experienced water hammer, particularly on colder days, mostly on the eastern risers. but occasionally in other areas. This is a relatively new boiler and we did experience some minor surging post install and, and so we bled and flushed it several times with water (which I now know can lead to mineral oxides but it seems like that was better than dealing with contamination) and after watching Gerry flushing out boilers with a garden hose this seemed to be the right approach. We have never had heavy sludge build up, but we have seen dirty thick rusty oxides in the water.

QUESTIONS IN SUMMARY

Based on readings here, I believe I could benefit from master venting the mains but I am concerned about getting water spitting out of a main vent if I install it. given that I am having this problem on the 2nd floor will the venting eliminate this? The basement is a finished basement, So I don't really want rusty water spraying from the ceiling. Is this a risk? how can this be overcome?

Gerry Gill and Steve Pajek, recommend venting the mains and the risers. I have access to the basement horizontal main, where I can tap a hole and, time the displacement. But I don't have access to the top of the risers because they're under the floor. The only access is at the valves connected to the radiators. Would it be recommended to drill and tap a a hole into the vertical 1" riser near the 2nd floor ceiling, could I vent the main first then only do this additional venting if the radiator vents are inadequate?

EBEBRATT-Ed

best bet would you to contact @JohnNY for a consultation. You can PM him

EdTheHeaterMan

Peter, I'll take Paul Lynde to block
Not everyone will get this

KC_Jones

For the water hammer and spitting vents I'm going to suggest the header on the boiler is undersized, the manual clearly states 3" for the header.

I will also suggest that boiler is massively oversized, unless those 9 radiators are each gargantuan in size.

Water spitting from vents could be caused by a couple things. The boiler is piped poorly causing wet steam to get up into the system. Somewhere in a horizontal piping run you have a sag or improper pitch causing water to lay somewhere it shouldn't. The boiler is massively oversized for the system which can amplify the previous two issues.

Symptoms of oversized boiler is short cycling on pressure because it's producing more steam than the system can handle. To be clear on this one, the pressurtrol is a safety device and really shouldn't be shutting off the boiler in normal operations. Unless you are willing to replace the boiler there isn't much that can be done about this one except live with it and the cycling. Venting can help a little with cycling, but only a little bit.

If you want help adding up the system EDR to see how oversized you are, we can help with that, it's pretty simple if the radiators are relatively standard.

As far as the other two scenarios you will need to access horizontal pipe runs and check the pitch with a level. Anything hidden can be tricky, but sometimes you can correct that by shimming radiators on the valve end to pull the pipe up, it typically doesn't need to go down.

EdSheridan

KC, I have not yet calculated the total EDR for the system but all of the radiators are pretty substantial.
Here is a photo. All the radiators are 38" tall. The 3rd floor radiators are 4 and 5 sections apiece and the 1st and 2nd floor radiators range from 11 to 15 sections each. Having no experience with EDR calculations, i've got no basis to work backward from at this point but it seems like the system has been working okay since 2017 when it was installed, I will double check the horizontal pitch of the mains because it seems like that could be a contributing factor. To confirm header here is 2.5" IPS.

The other peculiar thing is that I don't get any spitting on the first floor radiators only on Radiators in rooms 5 & 6

Jamie Hall

Are rooms 5 and 6 connected to their riser exactly as shown? Or is there a common runout from the riser which then separates?

KC_Jones

The header you have there is 2" pipe, the outlets on a Burnham independence are 2" and that header is obviously not upsized so it too is 3". You may be misidentifying which pipe is the header, I see a size increase on the main after it leaves the boiler header and turns vertical, that pipe is bigger, that is NOT the header. 2" pipe measures 2 3/8" OD. 3" pipe that is required for the header on that boiler measures 3 1/2" OD.

As far as the radiators, if they are all 2 tube like that, then they are 4 EDR per section, add up the total number of 38" tall sections, multiply by 4 and you have the EDR. The short on you pictured would be different and a side view and height measurement would be needed to check that one.

EdSheridan

Thanks for the EDR info and  correction on the header dimensions, I did measure the OD  and I thought it was 2-7/8 but I agree with your analysis it must be 2-3/8 OD. My understanding is the mains and risers also facto in the total EDR?

I could not find a BTU rating on this boiler.

(Going back to Hollywood squares,) The graphical representation Is not entirely accurate, the east riser from the basement is a 2” riser feeding a 2” to 1-1/4” IPS reducing tee which then branches out horizontally in the floor about 2’ away from the radiator in #5 and about 4’ away from the radiators in #6 then feeding the subsequent 1” riser going up and the 1-1/4” radiators in #5 (Paul’s) an 6.

KC_Jones

Mains and risers do not count towards EDR calculations.  There is a factor built into the boiler rating that covers this, probably a couple times over.

Jamie Hall

First place to look is for a pitch or water trap problem in that common piping to 5 and 6.

EdSheridan

Thanks Jaime, the issue is the horizontals are i. The floor. I’m reasonably sure there is a drain pitch on 

KC, The small radiator is a about 16” tall including the feet and about 13” heres a photo showing the top. 

For EDR im getting 74 (2 columns sections) x 4 = 296 total EDR, Plus this small radiator mentioned above. This is the total heating load, how is this number used to convert to BTU or boiler size? 

dabrakeman

You should be able to find a plate somewhere on the boiler that says what sqft of steam (EDR) it is rated for. Directly compare that to your total EDR from the radiators. If you can't find the information on the boiler (odd) then let the forum know what make and model it is and maybe it can be looked up.

SlamDunk

A quick google search says the IN8 is a 154kbtu output boiler. I sized a furnace in the bronx for my family and came up with @70kbtu requirement. Checked with neighbors and their boilers/ furnaces were in the 70kbtu range too. These are all three story detached homes.
I'm going to guess your boiler is over sized. 1 edr=234btuh

leonz

Yes contact @JohnNY.

KC_Jones

That small radiator is about 4-5 per section, let’s call it 5, 12 sections is another 60 EDR.  Add that to the 296 and we get 354.  The IN8 is rated for 633, so you are about 77% over sized.

2” header would most likely be fine if they installed the properly sized boiler, in this case an IN5 would have been more than enough.  This explains the cycling on pressure and there probably isn’t much you can do to resolve that particular problem, again unless you replace the boiler again.

This is why sizing is so important, and it’s not really that difficult which is why it’s so frustrating that a paid professional refuses to do it.

question

If you are able to hire someone to vent the top floor radiators like the photo I have attached this will get the risers vented quickly. Master venting and main venting are very important to bringing the steam throughout the building. The radiators should be vented based on there size not by what floor they are on.  

Water spiting out of your air vents is caused by condensation not returning back to the boiler and the steam pushing it out. You need to be a detective of sorts to find where water could be staying in the pipes. Some horizontal sections may have sagged after pipe hangers were removed. You can also check that the risers coming off the main is at a 45 degrees angle.  I have seen a building where they were put in on a 90 degrees angle and the condensate was being pushed back up the risers when the boiler went back on. 

Good luck. 

EdSheridan

Well, all I can say is that this has all been very educational. I guess this goes in the "tuition" category. Frankly there's a lot more to this sad story if you knew we had to have a new gas service brought in to fire this oversized beast. All this because of unprofessional (that's putting it mildly) plumbers. I really appreciate all the explanations. I guess at this point I need to know where to go from here. I don't think we're going to replace the boiler. Jamie or KC can you opine on the master venting questions? Would this help at all given the EDR issue?

KC_Jones

The short cycling is something you will most likely have to live with. Adding more venting should help with the beginning of the cycle, but once the vents close you will have the cycling on pressure issue as the system just isn't big enough to handle the steam production. Adding riser vents is a good suggestion, you want all that excess steam to be able to move as quickly as possible and start heating the radiators, after that the cycling will most likely begin. Personally I'd go for the venting, but before that, the header....

I personally don't think the water issue will be able to be fully gotten under control unless that header is sized properly at 3". It's really critical to get the boiler piping right to get dry steam, once the water leaves the boiler (it shouldn't ever), it gets infinitely more difficult to deal with it, if it can even be dealt with at all.

I don't see venting of any kind stopping the water from spitting.

I'm sorry about the luck you are having here, it just boggles my mind that these contractors won't take simple measurements to size a steam boiler properly, and then on top of it, pipe it incorrectly. I ended up installing my own boiler out of sheer frustration with the locally available contractors.

Long Beach Ed

Follow KC's advice. Address the problems one at a time. Get your venting in order so the system distributes steam quickly and evenly. Address any poorly pitched pipes. You might also insulate that header and the riser pipes too.

Radiators that spit condensate from their vents sometime benefit from slower venting. The smaller vent reduces steam velocity into the radiator which often helps condensate to leave the radiator. Over-venting sometimes causes or amplifies problems.

Burnham used to teach their engineers' classes that their gas boilers could be down-fired 20%. I would have your plumber check with them and see if that is still acceptable. If so, it may reduce or eliminate steam quality problems.

After these things are done, the header piping may be adequate or it may not. One thing at a time. Plenty of poorly piped, oversized boilers work well and efficiently. You may be lucky. It all depends on the design of your system.

Down the road, keep your water free from oil, pressure low and the pigtail on your pressure control clean.

Mad Dog_2

I  love your ORNATE radiators.   They are gorgeous.   All good advice.  You could always derate the boiler down quite a bit with a combustion specialist who knows his way around a combustion analyzer. That will help ameliorate some of the oversizing.  I would NOT change or add any main vents until you  get better handle on the system's behavior.  The best air vents are NOT cheap and you  don't want to destroy them in short order.  Mad 🐕 Dog. 

Steamhead

EdSheridan said:

Thanks Jaime, the issue is the horizontals are i. The floor. I’m reasonably sure there is a drain pitch on 

KC, The small radiator is a about 16” tall including the feet and about 13” heres a photo showing the top. 

For EDR im getting 74 (2 columns sections) x 4 = 296 total EDR, Plus this small radiator mentioned above. This is the total heating load, how is this number used to convert to BTU or boiler size? 

This is a "flue" radiator so its heat output is greater per section. It looks like an Aetna Flue by American Radiator Co. I'm getting 56 square feet on it.

Mad Dog_2

I remember the Great Flue radiator you drove  up from Maryland with and donated to This Old Farmhouse.   6 SQ FT EDR per section!  You and Noel both gave me great tips on the design.  Your names and Dan's are immortilized in the boiler platform slab:
"The Dead Men are alive and Well."   Mad Dog 

pjc_2

I would try this fix: Break the 2" union and remove the 3" x 2" elbow. Replace it with a 3' x 2" x 2" tee. Drip the bottom outlet back to the bottom of the boiler. Any water or steam getting pushed up that riser will fall into the return you just installed. Obviously your not going to change the boiler or dismantle and rebuild your header, so this may be a quick fix that works.

gmcinnes

I'm sorry about the luck you are having here, it just boggles my mind that these contractors won't take simple measurements to size a steam boiler properly, and then on top of it, pipe it incorrectly. I ended up installing my own boiler out of sheer frustration with the locally available contractors.

Ain't that the truth @KC_Jones

Those are really gorgeous radiators. Well done @EdSheridan

Mad Dog_2

Its pathetic.  I just did a Consult where the boiler was installed 3 yrs ago...two sections short of a loaf!  Only 75% of rads get hot.  Measure EDR versus boiler EDR...clear cut case.  No one wants to believe that is  the reason except the innocent homeowner
That is stuck in the middle with a pending house sale...Its very frustrating and sad when "professionals" won't do basic math and install atleast closely sized equipment. But I see it often 😕   Mad Dog

EdSheridan

Thanks for the comments on the radiators. We agonizingly took them down several flights of stairs and scraped, stripped, and repainted them, replaced all the valves. Only took us 6 years . We were missing one on the second floor but were able to snag an identical one from a house down the street during demolishion. 

Steamhead, I think you're right about the Aetna Flue Radiator, I ran across this old catalogue illustration of an Aetna Flue, which appears to be identical to ours.


The radiator is adjacent to the fireplace, kind of a modern steam twist on an old architectural design called an Inglenook.

The other radiators are all cast at Reading Radiator Co., of Penn., and they have a kind of strange pelican-dragon relief which I know must have some story but I haven't got any leads. 

So, talk about being upside down and backwards -- This is the front yard after the gracious Con-Ed inspectors determined that the building gas supply was way too small for our new boiler. (You think all these pros involved in all of this might mention that we are at about 185% oversized for the coldest day of the year.) This is insane.



All things considered -- Even given all this lunacy. I don't want to overstate the severity of the problems. Apart from the cycling on startup, which I always knew was not right (but now I understand it, thank you KC) The bottom line is that we do get consistent heat from the system.

At this point I just am primarily interested in knowing if I can benefit from master venting to cut down on some of the initial start-up lag and hissing, at least until things get hot and the vents close. I may be wrong but I would think this might also reduce some of the cycling. 

This is the western leg of the 2" main steam coming from left above, 1" below is the return.
What i'd like to do is drill and tap the cap of that 2" main and add an appropriately-sized Gorton main vent. and vents on the risers, at the 2nd floor ceiling. i'm not crazy about the look of questions master venting at the floor where the valve is. Sounds like its functional but id worry about someone stepping on it etc i'd prefer to have it close to the ceiling out of the way. 

It bothers me from a pragmatic and professionalism standpoint that the systems is not piped properly and my urge us is to eliminate the 2" to 3" reducing elbow from the origninal system and then  repipe the boiler with a 3" drop header but I know i'm going too far down the rabbit hole, given the degree of problem. i'd spend a bunch of money and 147 hours in the boiler room only to get marginal returns i'm afraid. 

I figure with 1 main vent and 3 riser vents at the ceilings of the 2nd floor, I figure I may be able to get some kind of balance? Should I bother?

Ed

Mad Dog_2

Take one step at a time to see how system behaves  mad dog. 

dabrakeman

You approach sounds reasonable. After getting the main and riser vents in see what radiator vents you can slow down.

SlamDunk

I wonder if you could take a couple sections of the boiler out and put in a smaller burner to make an IN-8 an IN -5?

Long Beach Ed

SlamDunk said:

I wonder if you could take a couple sections of the boiler out and put in a smaller burner to make an IN-8 an IN -5?

It could be done. The problem is that the base, hood and jacket along with some piping would have to be changed. We've done a few Burnham reductions back in the days when parts were easily available. It seems I can't get much from Burnham these days when it comes to parts like jacket panels... Lots of labor involved too.

ajc72

Reading through this thread and wondering if there was any solution? Seems like steam is condensing in that three inch riser and winding up in the upper horizontal mains.