Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Ironing out the kinks...

Hi all,

Sorry in advance for the long post; I'm a bit wordy.

My wife and I bought a 1918 colonial in northern NJ in 2020. We installed central air that summer and decided to keep the single-pipe steam, despite my early protestations. I work in construction and am relatively handy, but I never thought I would be the guy buying a big, old house and inviting the inherent maintenance while also trying to start a family. It is truly a labor of love.

The previous homeowners had a fire in 1997; the home was gutted and rebuilt in 1998. Everything was brought up-to-code with walls insulated, modern electricity installed, and plumbing updates where needed. A Peerless 61-06 200k BTU natural gas boiler was installed (not sure what they had before) and connected to the original steam piping, with some minor revisions here and there. At the time of purchase, our home inspector performed his rudimentary overview of the system and declared it 'functional'. We were informed that we probably had another thirty-or-so years of life in the boiler, and we were convinced by various parties to keep the steam heat.

Not knowing much (anything at all) about steam heat, I falsely assumed the system had been installed properly in 1998 and maintained properly since. The cracks literally and figuratively started forming during the first week of heating season in 2020. We had several cold radiators, occasional banging noises, and seemingly high gas bills. While wrapping up some loose ends, the central air installer replaced our two old, cheap, crusty main vents with Gorton #1s. I started doing some research on steam heat, frequenting this forum through google search results, and I even added 'The Lost Art....' to my Christmas wish list at the risk of becoming the butt of my many in-laws' jokes. Shortly thereafter, I soaked the fifteen Heat Timer Varivalve radiator vents in some hot vinegar and seemed to get a few of them breathing again. I also replaced all of the controls fittings, adding a new 0-30PSI main gauge on a new pigtail, and a 0-5PSI gauge adjacent to the pressuretrol with a new pigtail serving both. We had some colder rooms throughout the home, but the system was working well enough to focus on various bigger fish in need of frying. I blew down the LWCO every 1-2 weeks, added water as needed, and called it a day for the year.

At the start of the current heating season, I replaced all radiator vents throughout the home with Vent-Rite #1As and set them roughly where I thought they should be set, being too lazy/busy to do calculations right now. I also had another HVAC guy come in to perform basic boiler maintenance; I believe he just flushed the return pipe and cleaned out the controls piping and LWCO. Regardless, I finally had every radiator getting warm, but then I seem to have opened a can of worms after an unintentionally large setback recovery one day in early December. One of my Gorton #1 main vents was getting stuck open, causing my second and third floors to get quite warm while the boiler continued to build pressure and run itself down until the LWCO kicked in. Okay, truth be told, I accidentally placed my large console humidifier RIGHT below the thermostat (dunce cap) and realized after one day that this was a very bad idea. It was after this debacle that I really started researching and digging into my system. So far, I have identified the following "deficiencies" needing to be addressed:

1. Near-boiler piping. My header is just a mess. The header itself is too low, there are no offsets, and both main takeoffs are between the boiler outlets. Did I mention it's a mess? I'm fairly certain I'm getting a ton of water up in the system, causing repeated problems with one of the main vents. I also have some copper pipe there, but I know it converts to black pipe somewhere inside that insulation; everything else throughout the system (away from the boiler) is black pipe. My thought process here is to add offset elbows facing the wall behind, reroute the header so it exits to the right side of the boiler, elbow down and back toward left side, takeoff both mains, and finally connect to equalizer piping. Also assuming all copper should be replaced with black pipe. Obviously none of this work would take place until the summer, and I'm debating whether or not a handy homeowner should attempt this by himself. Also debating if all of this work is worth doing on a 23 year-old boiler. Thoughts?

2. Skim tap. The HVAC contractor who maintained the boiler wasn't sure why I would have a valve on the skim tap. There is a badly corroded nipple (I think?) between the skim tap and said valve (was leaking slightly during the high pressure incident), so I need to do something with the tap. Should I just get rid of the nipple and valve assembly and just cap the skim tap?

3. Main piping (2-inch). A significant portion of one main is uninsulated, which likely happened when we had the drywall ceiling removed in the whole basement to help with A/C duct routing. I know this needs to be remedied to avoid steam condensing before it hits the risers, but are the 3-ft sections of fiberglass pipe insulation really my only option? Seems time-consuming and expensive, but I can't find a source that sells longer pieces. While I'm at it, is it really necessary/beneficial cost-wise to insulate the return piping? Most of my return is currently uninsulated.

4. Main venting. Both main vents are taken off with a 1/4" tap at the return drop. Obviously this is wrong for several reasons, but I am somewhat limited on relocation of both taps. The longer main (about 50-ft of 2" pipe) now has ductwork above the last ~18" and has two takeoffs immediately before the ductwork, so I cannot tap the top of the pipe here. My thought process is to tap the side of the main a few inches after the last takeoff, then elbow and long nipple back away from the wall, then up as high as possible either into a single Gorton #2 or split into two vents with a tee, if necessary. Thoughts on this arrangement and on quantity/type of vents?

The shorter main (about 40-ft of 2" pipe) also has its final takeoff shortly before the return drop, so I cannot come back the recommended 12" from the drop for my vent. I am thinking of tapping either the side or top of the main a couple of inches past the takeoff, and assuming a 1/2" tap with a single Gorton #2 for this main. Or maybe I can stick with the single #1 I've got on there. Thoughts?

5. Radiator pitch. I was able to pitch most of the radiators back toward the pipe ever so slightly with minor shimming. However, two radiators on the third floor were moved away from the wall to accommodate the cooling ductwork now running around the third floor perimeter. The plumber who did this work replaced the old 90-degree valves with elbows, nippled out to the new radiator location, and installed straight valves before the radiators. I don't see an issue with this arrangement per se, but the new elbow at the top of both risers seems to be 'aimed down' very slightly rather than exiting horizontally, if that makes sense. the additional length added by the nipples exacerbates the low point and resulting condensate trap at/near the straight valves. I tried shimming both radiators up enough to correct the pitch, but it doesn't seem possible. I actually cracked the threads on one of the straight valves and found out the hard way after cupping a bit of my wood floor below the valve. The silver lining is that I now know how to replace a radiator valve and spud! Anyway, how critical is radiator pitch? If these two radiators on my third floor just cannot be pitched properly but they still heat, albeit with some noise, is it the end of the world? Or is there another solution?

So I think that's all I've got for now. Apologies again for the novel, and thanks in advance for any input. Cheers!


  • Jamie Hall
    Jamie Hall Member Posts: 23,303
    Apologies not required. There is no such thing as too much information -- all too often the complaint is just the opposite.

    Before I comment, though, may I ask if you have the excellent book 'The Lost Art of Steam Heating"? It's available through this site (in the store) or, if you prefer, thought Amazon. It's a bit of a read -- but it is also the encyclopaedia for understanding and working on steam heating systems.


    You have correctly identified that the near boiler piping -- the piping between the boiler and the steam mains -- leaves something to be desired. Your proposed solution is quite good. There are more complex ways to do it -- look up "drop header" -- but not totally necessary. What is necessary -- and one of several reasons for using black iron -- is that there be a little flexibility in the connections between the boiler takeoffs and the header, to accommodate expansion. It is also important that the pipe sizes be adequate. The general recommendation is that the headers should come off the boiler with no reduction in size, and that the header be one pipe size larger. The equalizer at the far end is connected with a downturned elbow, and only then reduced in size to the equalizer. Black pipe (never galvanized steel) is strongly recommended, as mentioned. This is something which a plumber can do -- under supervision -- but if you are handy I won't say you can't do it yourself, if you are in construction.

    On the two radiators which got moved. If the noise is tolerable, and they heat well, I'd leave them alone.

    Insulation. My feeling is it should be done. Generally the stuff is sold in 3 foot lengths. Two known good sources are supplyhouse. com and https://www.buyinsulationproductstore.com/Fiberglass-Pipe-Insulation-SSL-ASJ/. I'd suggest 1 inch. I would also suggest the 1 inch thickness. It's sold to fit specific iron pipe sizes. I'd insulate everything that carries steam, at least in the basement.

    Which brings up returns. There are returns -- and then there are returns. If the pipe in question is at a high level, and it connects directly to a steam main, it really isn't a dry return; it's a steam main extension. This is of significance in two ways, first, as you know, it needs to be vented. Second, and perhaps less obvious, if you have two of these things, they must not connect to each other at the far ends, but they should have a drip at the far end to return any condensate to the boiler, and they need to be vented individually.

    Is there a monetary return on insulating steam mains? Probably not. What insulation will do, however, is reduce the amount of condensate in the mains, which is always good, and increase the speed with which steam will get throughout the whole system -- sometimes quite substantially.

    Main vent locations -- yes, it is ideal to have them off the top of the main, and some distance back from the end -- but there is no harm to having them come off the side and then turn up, provided that any more or less horizontal sections are pitched to drain any water back to the main, as any water trapped will be blown up into the vent which will then spit at you. If you are dealing with a steam main extension, any location after the last radiator takeoff will do. I'd suggest a Gorton #2 for both of those mains.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Steamhead
    Steamhead Member Posts: 16,841
    You really need a Steam Man there- fortunately North Jersey has quite a few good ones. @EzzyT , @clammy and @JohnNY come to mind. See the list here:

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • EzzyT
    EzzyT Member Posts: 1,295
    @thebigdu you can reach me at 2018878856
    E-Travis Mechanical LLC