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Water hammering problem in single pipe steam boiler system (residential)

I live in a 1920s house in Central Pennsylvania, and have had water hammering in the steam boiler system for the last 2 years. We were used to the regular hissing, ticking of a steam boiler heating system, but it started getting incredibly loud and waking us in the night when the heat kicked on and water started running through cold pipes.

Local HVAC companies don't seem to have the expertise to figure out what's going on, so I thought I would check here and see if this community knows of steam boiler pros in Central PA--I'm in State College. So far this is what we've tried:
1. 8-way flushed through system, allowed to sit in boiler over the summer months in 2022
2. replaced old steam vents in at 2 radiators
3. checked level of pipes to make sure they were graded to drain properly (all seem to be graded properly)
4. lowered psi to 1.5 (it was set too high apparently)

Comments

  • mattmia2
    mattmia2 Member Posts: 9,469
    Is the 8 way still in there? Too much treatment in the water will cause it to prime (foam) and carry water up in to the system. Is the water level in the sight glass stable while it is steaming?
    EBEBRATT-EdMad Dog_2
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,606
    edited October 2023
    Your home may be settling or some termite damage may have caused the floor under a radiator to fall enough to upset the proper drainage of condensation from the radiator. A pipe hanger may have broken loose and now the improper pitch of that pipe may be causing water to pool where it should not. What @mattmia2 said... and many more reasons.

    Have you tried to call someone from the Find a Contractor link above? https://heatinghelp.com/find-a-contractor/state/PA. Look like there are 2 in East central and west central PA. and I know that State College is in Central Central , PA. My sister went to college there.

    You need to ask around the plumbing supply companies near you to find a good steam man. they know their customers.
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    Mad Dog_2
  • neilc
    neilc Member Posts: 2,672
    you set your pressure down,
    did you service the pigtail between the control and the boiler?
    Can you breath / blow freely from the Ptrol into the boiler?
    Pictures there?
    known to beat dead horses
    Mad Dog_2
  • Mad Dog_2
    Mad Dog_2 Member Posts: 6,757
    Is that in the Nittany Mountains near Penn State?  Mad Dog 🐕 
  • retiredguy
    retiredguy Member Posts: 888
    Can you show the types of radiation that is installed and has anything been changed in the system recently. Pictures of the boiler rads and piping will also help.
    Mad Dog_2
  • Mad Dog_2
    Mad Dog_2 Member Posts: 6,757
    And...Just because you "think" you've cleaned the boiler, system and wet returns, thoroughly...don't be so sure.  Mad Dog 🐕 
  • ChrisJ
    ChrisJ Member Posts: 15,496
    hannahc said:

    I live in a 1920s house in Central Pennsylvania, and have had water hammering in the steam boiler system for the last 2 years. We were used to the regular hissing, ticking of a steam boiler heating system, but it started getting incredibly loud and waking us in the night when the heat kicked on and water started running through cold pipes.

    Local HVAC companies don't seem to have the expertise to figure out what's going on, so I thought I would check here and see if this community knows of steam boiler pros in Central PA--I'm in State College. So far this is what we've tried:
    1. 8-way flushed through system, allowed to sit in boiler over the summer months in 2022
    2. replaced old steam vents in at 2 radiators
    3. checked level of pipes to make sure they were graded to drain properly (all seem to be graded properly)
    4. lowered psi to 1.5 (it was set too high apparently)

    Please show us some pictures of the boiler and the piping around, and above it. Try to stand back so we can see everything clearly, if possible.

    Also give us some pictures of a few radiators please.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    Mad Dog_2
  • hannahc
    hannahc Member Posts: 7
    Thank you all for your comments and suggestions!
    1. @mattmia2, one heating company did do an 8 way treatment and then left the 8way in the system. Another heating co. said that was not a good idea, and that the 8 way could have eaten away at the pipes and kicked up sediment into the system. Multiple people have suggested the water in the system is very dirty, and we do have very hard water here. We installed a water softener system in summer of 2020, partly to protect appliances and pipes from effects of hard water.
    2. @EdTheHeaterMan thank you for those suggestions! Those companies are all fairly far from State College, but worth calling them. I will also ask local plumping supply companies, that's a great idea.
  • hannahc
    hannahc Member Posts: 7
    Continuing here, with pictures:
    3. @neilc I believe we did have the pigtail serviced, but I'm not sure about being able to blow freely from the Ptrol into the boiler. I will ask about this. Pics attached of pigtail and pressure control.
    4. @Mad Dog_2 yes we're near Penn State :).
    5. @retiredguy here are some pictures of the radiators, boiler, and pipes. Yes, one company just added a vent to the system, see circled in blue (added it last month). They thought vent would help solve the hammering problem:





  • KC_Jones
    KC_Jones Member Posts: 5,707
    hannahc said:

    Thank you all for your comments and suggestions!
    1. @mattmia2, one heating company did do an 8 way treatment and then left the 8way in the system. Another heating co. said that was not a good idea, and that the 8 way could have eaten away at the pipes and kicked up sediment into the system. Multiple people have suggested the water in the system is very dirty, and we do have very hard water here. We installed a water softener system in summer of 2020, partly to protect appliances and pipes from effects of hard water.
    2. @EdTheHeaterMan thank you for those suggestions! Those companies are all fairly far from State College, but worth calling them. I will also ask local plumping supply companies, that's a great idea.

    You are definitely getting a lot of bad information. Water treatment doesn't leave the boiler, steam leaves the boiler, which is only the water molecules as the rest doesn't vaporize at the same temperature. The 8 way won't eat anything, it's actually intended to do the opposite, stop or limit the corrosion. It's kind of sad that a professional, getting paid to know that, doesn't.

    I'd be cautious about using softened water in the steam boiler, that can actually lead to corrosion because of what is done to the water to soften it.

    If you post some pictures of the boiler as @ChrisJ suggested we may be able to identify some issues.

    And to be clear, when steam is working properly, it shouldn't make any noise, anyone telling you otherwise is factually incorrect. So silence should be the goal, how easy it is to get yours silent depends a lot on what has been done to the system since install. As @ChrisJ suggested, pictures will probably tell the tale.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • ChrisJ
    ChrisJ Member Posts: 15,496
    @hannahc

    Can you post pictures showing this area from other angles? It's hard to see what exactly is going on.


    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • KC_Jones
    KC_Jones Member Posts: 5,707
    I was typing while you were posting pictures.

    Boiler is piped wrong, I'd say that is most likely a big part of the problem.

    We may need more pictures because the system piping looks messed up too. It has earmarks of a counterflow, but the pipes being connected as they are, with a vent on one side and a drip on the other, is wrong in some way shape or form.

    At the very end of your main (far away from boiler) is there a pipe that turns down and then returns back to the boiler? Most likely a smaller pipe if it's there.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • hannahc
    hannahc Member Posts: 7
    @KC_Jones I worry that I have been getting bad information, and often conflicting--one person will tell me one thing, and another will say the exact opposite.

    @ChrisJ and @KC_Jones I'm attaching more pictures to hopefully give more detail on piping in and out of boiler:







  • hannahc
    hannahc Member Posts: 7
    I'm wondering about the water softening and the effects on an old system (nearly 100 year old pipes), per @KC_Jones comment. The only major change we made to the systems that affect the boiler was in summer 2020 installing a water softening system. Minor water hammering started winter 2021, continued winter 2022 and 2023. Now at a severe level. Do others think the water softener could be (at least partially) to blame?
  • mattmia2
    mattmia2 Member Posts: 9,469
    The combination of the riser being reduced, the header probably being too small and the equalizer being in the wrong location means that boiler is very likely going to throw water up in to the mains.
  • Jamie Hall
    Jamie Hall Member Posts: 22,954
    hannahc said:

    I'm wondering about the water softening and the effects on an old system (nearly 100 year old pipes), per @KC_Jones comment. The only major change we made to the systems that affect the boiler was in summer 2020 installing a water softening system. Minor water hammering started winter 2021, continued winter 2022 and 2023. Now at a severe level. Do others think the water softener could be (at least partially) to blame?

    Yes, it could. Do NOT use softened water in a steam or hot water boiler. It is very aggressive and will shorten the life of the boiler. Further, if it is very soft, it can foam and cause carryover -- and water hammer.

    If you system doesn't leak -- which it shouldn't -- you are quite safe using even rather hard water, but you can alos use deionized or distilled water for the initial fill.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • KC_Jones
    KC_Jones Member Posts: 5,707
    hannahc said:

    I'm wondering about the water softening and the effects on an old system (nearly 100 year old pipes), per @KC_Jones comment. The only major change we made to the systems that affect the boiler was in summer 2020 installing a water softening system. Minor water hammering started winter 2021, continued winter 2022 and 2023. Now at a severe level. Do others think the water softener could be (at least partially) to blame?

    No. What leaves the boiler and goes through the system is essentially pure water, regardless of what liquid is sitting in the boiler. This is a way of actually purifying water, boil, collect the steam, condense and you have purified water.

    Why it is getting worse could be due to settling or other factors, but one thing I'm sure of is that the piping is not correct and could be the biggest factor here.

    Question, is there any other pipe besides the red one that connects to the blue one? Hard to make out in the pics you posted. That's the return, and figuring out how the water gets back to the boiler, may help us figure the system out and recommend fixes.


    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • Mad Dog_2
    Mad Dog_2 Member Posts: 6,757
    That pigtail has not been out in a while unless they cleaned off the threads perfectly.  P Trol...yes...Pigtail no.  Mad Dog 🐕 
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,606
    edited October 2023
    EDIT
    KC_Jones said:

    I was typing while you were posting pictures.

    Boiler is piped wrong, I'd say that is most likely a big part of the problem.

    We may need more pictures because the system piping looks messed up too. It has earmarks of a counterflow, but the pipes being connected as they are, with a vent on one side and a drip on the other, is wrong in some way shape or form.

    At the very end of your Main (far away from boiler) is there a pipe that turns down and then returns back to the boiler? Most likely a smaller pipe if it's there.

    Like to see a picture of that pipe at the end of the Main if it is there

    From one of your other pics I see a RETURN drop near the boiler indicating that you may not have that return drop at the end of the Main. That would make it a counterflow one pipe steam system. no return at the end of the Main because the condensate runs backwards down the Main, in the opposite direction of the steam. If that is the case, then proper pitch of the Main is even more important.

    End of edit

    From the pictures I see This is what I can get as to the way your header is piped
    Not the exact model number of your heater but Figure 4.3 is from HB Smith model GSX manual


    Next to the factory diagram is what I believe you have. There are three things stand out as a problem
    1. The first fitting out of the boiler can not be a reducing coupling. That must be full size vertical (Riser) until it turns into the horizontal pipe (Header). The I/O manual will tell you what the Header size must be, based on the boiler size. It may call for using both sides of the boiler (2 Risers) into one header.
    2. The riser and header are too small
    3. The riser goes in two directions. How is the Steam supposed to know that it is to go to the leaf and the condensation is supposed to go to the right? I don't think there are directional arrows inside those pipes to let them know. Even if there were, Is your water smart enough to know how to read directions? If it is male water then probably not, It might if it is female water.


    In the factory recommended pipe design, the riser from the boiler, only goes one way. The steam and any water will both go towards the steam system riser. When the steam goes to the tee, it will rise to the system. The heavier water will roll past the tee and return to the boiler thru the equalizer. (that is the turned down pipe that goes back to the bottom of the boiler where the Hartford Loop close nipple is located)

    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    mattmia2bburdjringel
  • hannahc
    hannahc Member Posts: 7
    @EdTheHeaterMan thanks for those diagrams--they're very helpful. Yes, I do believe it's a counterflow one-pipe system. This is what I've been told by all of the people checking it out. Do you think those three problems could be solved by a specialist who's experienced working on steam boiler systems? @KC_Jones I'm not sure if that answers your question about the return line, but I did take a couple more pictures in case they clarify the situation.







  • KC_Jones
    KC_Jones Member Posts: 5,707
    edited October 2023
    No other returns so a counter flow system for sure. Just to be very clear, each of those mains goes out around the house and ends, with a cap, doesn't continue on anywhere else, correct? So you have 2 mains, and both have a cap at the end somewhere in the house?

    1. Header isn't configured correctly
    2. Header appears undersized, but would need the exact model and locate the install manual to know for sure.
    3. Configuration of mains is incorrect.
    4. Drip missing on second main (why I asked if there was another return somewhere for that side)
    5. Main vent in the wrong location, main vents need to be at the end of the main. We don't have pictures of that to know if there is a provision for them, or if fittings or a tapping will need to be added.

    I am attaching a crude picture showing how it should be configured. Red is what goes away, blue is what should be piped. The drip on the second main would tie in near the other drip BELOW THE WATER LINE of the boiler, that is an important detail not shown in the picture. It still boggles my mind that a professional gets this wrong, there is a picture in the manual showing how to do it.





    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • hannahc
    hannahc Member Posts: 7
    @KC_Jones thank you for your explanation and diagram! And thanks to you all for the feedback you've provided; it's been really helpful. I'm so grateful to find all this expertise in this forum!