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.

Post cycle noise

Options
coachgvaz
coachgvaz Member Posts: 16
in Strictly Steam
Hello all:

After my gas steam boiler cycles , it is making a thumping sound every 20 seconds or so for a minute or two. It just seems odd as it’s never done that before. Btw, boiler is running fine. House is warm. Should I be worried? Is this a potential problem ? I have video but can’t upload - seems only pictures can be uploaded

Comments

  • Fred
    Fred Member Posts: 8,542
    Options
    Can you isolate the specific area of the thump? It is most likely expansion/contraction noise from a steam main or radiator run-out where the pipe is against a floor joist or where the radiator run-out pipe comes through the floor and is rubbing against the wood floor or subfloor. If you find the location, use a strip of a plastic milk carton to put between the pipe and wood and see if that resolves the problem. If it does, you can decide if anything else is warranted. Plastic milk cartons are good for up to 325 degrees so don't worry about it melting.
  • coachgvaz
    coachgvaz Member Posts: 16
    Options
    Thanks for the reply . The noise is coming from the actual boiler. I’m in the basement watching the TV. I’m hearing the sound from the boiler room. Checked it out . When the boiler shuts down After it’s cycle and the condensate returns I hear a thumping sound from within the boiler. New sound. Never heard it before.
  • Fred
    Fred Member Posts: 8,542
    Options
    coachgvaz said:

    Thanks for the reply . The noise is coming from the actual boiler. I’m in the basement watching the TV. I’m hearing the sound from the boiler room. Checked it out . When the boiler shuts down After it’s cycle and the condensate returns I hear a thumping sound from within the boiler. New sound. Never heard it before.

    How old is the boiler? When was it last serviced? Is it gas or oil? It almost sounds like the thump may be fuel related, post ignition maybe? It should be checked out by a qualified professional.
  • coachgvaz
    coachgvaz Member Posts: 16
    Options
    32 years old. Gas. Serviced in September. Every year it gets serviced. Running fine. Heating the entire house. After it runs it cycle it making a thumping sound for like 2 mins every 15-20 seconds. I can hear the condensate as usual returning to the boiler. Never have heard that thump.
  • Fred
    Fred Member Posts: 8,542
    Options
    coachgvaz said:

    32 years old. Gas. Serviced in September. Every year it gets serviced. Running fine. Heating the entire house. After it runs it cycle it making a thumping sound for like 2 mins every 15-20 seconds. I can hear the condensate as usual returning to the boiler. Never have heard that thump.

    Is it oil or gas? It will heat normally and condensate will return normally but the Burner may need adjusting or there may be a small fuel leak somewhere in the burner area.
  • coachgvaz
    coachgvaz Member Posts: 16
    Options
    Gas
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,837
    Options
    I had a problem that I wanted to post the video, so I posted it to my business Facebook account and posted the link here. "Is there a Ghost in Boiler Number 1?"

    If you don't want everyone here to see your personal social media, maybe you can make up a new separate account to post the video. (I find that grandchildren can do this with ease) once the link is posted here then we can see and hear the thump and have a better idea of what you are experiencing
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics

Categories