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Pls Help! Steam Boiler wont shut off during shoulder season

Hi there,

Im the owner of a 5 unit apartment building in Massachusetts that is 130+ years old. It has steam heat and original radiators. The boiler is from 2007 I believe.

I used to live in the building and had the thermostat in my apartment. For as long as I lived there, the heat would go full bore during the shoulder heating season of September-November. The thermostat is set to shut off at 68 during the day and 64 at night. But the radiators would be burning hot to the touch while the tstat is reading 73, 78 or 81. It would not turn off at night at all as it is set to. During shoulder season it is between 50-60F during the day and 39-45F at night.

We have varivalves on every radiator. When I lived in the building I would turn the heat off when the tstat was not calling the boiler to shut off. But now that I moved out, the tstat is in a tenants apartment, locked in a heavy duty metal grainger (i believe) box.

And the tenants are dying from the heat. They have their windows open. The tenant with the thermostat reinstalled her AC in Late october. Im pouring money out the window because of this issue and I dont know what to do.

The thermostat is a battery operated honeywell. Batteries are being replaced tomorrow but that hasnt helped this issue in the past.

Please help, my plumber cant figure it out. He tested the wires to make sure there isnt a short and he was able to get the boiler to turn off and on when turning up and down the tstat temp but it has a life of its own and turns on when its not supposed to and brings the indoor heat up to high 70'sF.

Thanks!!

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 22,928
    Make and model of thermostat?

    Placement of thermostat? Exterior wall? hole in the wall blowing cold air on it? Is the thermostat level (some are very sensitive to that).
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • 109A_5
    109A_5 Member Posts: 1,343
    Hello @AuntJuicy,

    A second thermostat hidden and forgotten about somewhere else in the building. Intermittent chafed thermostat wires.

    When the building is overheating, If you disconnect the known thermostat does the boiler shut off, it should, if not, disconnect the thermostat wires at the boiler, does it shut off then ?

    What shuts it off in the Summer ?

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • ethicalpaul
    ethicalpaul Member Posts: 5,611
    It seems like you must have known that if you weren't there to shut off the heat in the shoulder seasons, that it would be running all the time, costing you tons of fuel dollars...how is it possible that you don't have a service contract with an HVAC contractor as the owner of a residential building? Sorry if this is sounding judgmental, but that would be the first thing I would do.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
    pecmsg
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,329
    Does the boiler also heat domestic hot water?

    Make sure the thermostat isn't sensing cold drafts. The hole in the wall behind the thermostat where the wires come in should be filles with insulation or tissue paper.

    If the boiler does not also make domestic hot water and you only have that one thermostat to control the boiler and the thermostat does not shut down the boiler when the room temp at the thermostat is above set point then

    Either the thermostat is bad

    the heat anticipator or cycles/hour in the stat could be set wrong

    you have a short in the thermostat wires

    or the thermostat is not wired right.
  • AuntJuicy
    AuntJuicy Member Posts: 8
    @Jamie Hall Im not sure of the model of the thermostat. Its a pretty standard no frills honeywell thats a couple years old. Its located on the interior wall. It appears to be level. Im not sure about the hole in the wall. It works fine when its very cold outside so I cant imagine its the thermostat.
  • AuntJuicy
    AuntJuicy Member Posts: 8
    @109A_5

    There is no second thermostat. The boiler can be shut off when overheating by turning off the heating option on the thermostat. The thermostat shuts off the boiler in the summer. And in the winter, it does not call for heat once the 68 setting is reached. Occasionally it could go up 1 or 2 degrees but its nothing like the shoulder season.
  • AuntJuicy
    AuntJuicy Member Posts: 8
    @ethicalpaul First off, I came here for help because Im out of options and your response is rude and judgemental. How is that helpful in anyway? It says much more about you, then anything else.

    Secondly, I have a plumber who has been maintaining this building and its heating system for 7 years. He has not been able to find a solution. So how about you stop jumping to conclusions and just mind your business if you have zero to contribute.
    ethicalpaul
  • AuntJuicy
    AuntJuicy Member Posts: 8
    @EBEBRATT-Ed There is an indirect hot water heater. Would a draft in the hold of the thermostat affect the thermostat during the winter months as well? Because I dont have this issue when its actually cold outside.
  • pecmsg
    pecmsg Member Posts: 4,696
    AuntJuicy said:

    @ethicalpaul First off, I came here for help because Im out of options and your response is rude and judgemental. How is that helpful in anyway? It says much more about you, then anything else.

    Secondly, I have a plumber who has been maintaining this building and its heating system for 7 years. He has not been able to find a solution. So how about you stop jumping to conclusions and just mind your business if you have zero to contribute.

    This issue has been going on for 7 years?

    Plumbers are not my 1st choice when it comes to Steam.
    ethicalpaul
  • KC_Jones
    KC_Jones Member Posts: 5,704
    My guess, boiler is massively oversized, heats extremely fast, thermostat shuts boiler off, hot radiators continue heating building and the system overshoots. This is a common thing. Sometimes you can improve it with thermostat settings depending on which one you have. Really old ones had an anticipator, some newer models have a CPH setting which is intended to shut the boiler down before set point to allow things to catch up. Honeywell also has an adaptive learning feature in theirs to allow it to learn how fast the system heats the building and fire the boiler accordingly. All of these features fall into the category of your mileage may vary, some people get them to work ok, some can't get them to work at all. Depends on the building and system.

    Have you verified the boiler is actively firing when the thermostat is showing the room is over the set point. Not asking if the system is still heating as it will heat with the boiler off due to the nature of cast iron radiator heating, asking if the boilers burner is actively firing with a 68 setpoint and say 70 room temperature.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • ethicalpaul
    ethicalpaul Member Posts: 5,611
    AuntJuicy said:

    @ethicalpaul First off, I came here for help because Im out of options and your response is rude and judgemental. How is that helpful in anyway? It says much more about you, then anything else.

    Secondly, I have a plumber who has been maintaining this building and its heating system for 7 years. He has not been able to find a solution. So how about you stop jumping to conclusions and just mind your business if you have zero to contribute.

    I assure you I am all about empowering homeowners and DIYers to understand and be able to work on the systems in their homes. But you are a landlord, legally responsible for the safety and comfort of 5 individuals and/or families in this building.

    That is not the situation to be floundering around with your plumber who obviously is useless to solve this problem. It's one thing to make your spouse uncomfortable while you figure stuff out, but you are at financial and legal risk here. My advice, which I'm sorry, but it was not rude, stands up.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
    pecmsgWMno57Larry WeingartenPeteA
  • WMno57
    WMno57 Member Posts: 1,234
    Your plumber may be a great plumber. Steam heat is a niche subset of experience which your plumber may not have.
    https://www.heatinghelp.com/find-a-contractor/state/MA
    10 listings in Massachusetts. One in Boston, and maybe more that are close enough to Boston.
    We may be able to offer additional suggestions if you post some pictures of the boiler. Nameplate, size, and stand back to get the near boiler piping in the picture.
    I DIY.
    pecmsgdabrakemanethicalpaul
  • ChrisJ
    ChrisJ Member Posts: 15,462
    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
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,329
    @AuntJuicy

    So now we know that you also heat domestic hot water from the boiler. It is possible there is a problem with the control set up that runs the indirect water heater?

    This is because the control on the indirect heater if it is installed and wired properly will start the boiler and the circulator to provide domestic hot water.

    If those controls are not installed or set properly you could be making steam even if you do not need heat.

    The hole in the wall behind the thermostat where the wires come through should be plugged. This is because in older buildings there are sometimes cold drafts in the wall that can affect the thermostat.
    bburdPeteA
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    pecmsg said:
    @ethicalpaul First off, I came here for help because Im out of options and your response is rude and judgemental. How is that helpful in anyway? It says much more about you, then anything else. Secondly, I have a plumber who has been maintaining this building and its heating system for 7 years. He has not been able to find a solution. So how about you stop jumping to conclusions and just mind your business if you have zero to contribute.
    This issue has been going on for 7 years? Plumbers are not my 1st choice when it comes to Steam.
    Really? We are still doing  anti plumber thing
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
  • ethicalpaul
    ethicalpaul Member Posts: 5,611
    Only if they can't figure out a problem after 7 years, Charlie :sweat_smile:
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
    pecmsg
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    @ethicalpaul your post was general and you know it was not just this specific case. If it was " my oil guy" can't fix it after 7 years what would your witty retort have been?
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
  • ethicalpaul
    ethicalpaul Member Posts: 5,611
    edited October 2023
    Have a look up there, Charlie, I don't think it's my comment you are thinking of. My comment was not general to plumbers, it was specific to the poster's plumber. There was another comment that was general that was not mine.

    If a plumber is good at steam, I say all the better.

    And I guess if someone's oil guy can't fix their steam problem after 7 years, they should also go try to find a steam specialist.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    To the original post. This is something that would likely not be able to be solved online. You need a competent troubleshooter to go down and look over the controls of the boiler.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
    WMno57ethicalpaul
  • AuntJuicy
    AuntJuicy Member Posts: 8
    @KC_Jones I have not verified this year that the boiler is stull running while setpoint is reached on tstat because I dont live in the building anymore. But last year I can confirm that the thermostat would reach 75 and the boiler would still be running and I actually shut the boiler off because it was so hot and I couldnt stop it. This year the plumber who is also a heating and cooling tech verified that the boiler seems to be turning off when the setpoint is reached. My tenants are still boiling and opening windows. Perhaps the boiler is overshooting, I dont know.
  • AuntJuicy
    AuntJuicy Member Posts: 8
    @ethicalpaul My plumber is a heating and cooling tech in addition to doing plumbing and delivering oil. Thanks for the reminder that I am legally and financially responsible. I had NO IDEA. SMFH.
  • ChrisJ
    ChrisJ Member Posts: 15,462
    edited November 2023
    AuntJuicy said:

    @KC_Jones I have not verified this year that the boiler is stull running while setpoint is reached on tstat because I dont live in the building anymore. But last year I can confirm that the thermostat would reach 75 and the boiler would still be running and I actually shut the boiler off because it was so hot and I couldnt stop it. This year the plumber who is also a heating and cooling tech verified that the boiler seems to be turning off when the setpoint is reached. My tenants are still boiling and opening windows. Perhaps the boiler is overshooting, I dont know.

    There's several reasons this would happen.

    One is the thermostat isn't really meant for high mass heating systems, or, it's configured improperly.

    Another reason is the thermostat is located in an area far from a radiator or heat source, or it's being blocked from good air flow.

    By the time the air around the thermostat heats up enough to shut off, the radiators are already grossly overheated and keep putting off heat into the space for a good 30-60 minutes after the thermostat shut the system down. Cast iron radiators have a good amount of mass and hold a fair amount of energy that slowly dissipates into the room long after the boiler turned off.

    A proper thermostat will attempt to predict this and although they aren't perfect they do ok as long as they're setup correctly and have good circulation around them.
    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
  • AuntJuicy
    AuntJuicy Member Posts: 8
    @Charlie from wmass I agree. I just left you a voicemail, hoping you might be able to come take a look. Im in western mass as well.
  • ChrisJ
    ChrisJ Member Posts: 15,462
    I have no doubt Charlie can get it straightened out.

    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
    ethicalpaul
  • 109A_5
    109A_5 Member Posts: 1,343
    Hello @AuntJuicy,

    If it is not thermostat related or something to do with the DHW heating control, maybe the Gas valve is sticking open for a while after the call is satisfied. This may be more noticeable in the shoulder seasons.


    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • ethicalpaul
    ethicalpaul Member Posts: 5,611
    AuntJuicy said:

    @ethicalpaul My plumber is a heating and cooling tech in addition to doing plumbing and delivering oil. Thanks for the reminder that I am legally and financially responsible. I had NO IDEA. SMFH.

    I appreciate the continued sarcasm and disdain, no problem. Keep paying him for 7 more years, maybe he'll figure it out for you.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
    PeteA
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    @ethicalpaul perhaps you missed the mansplaining you were doing. The op is aware of her obligations as a property owner and has a heating contractor who has a stellar reputation if you were to research them in the area working on this. She is simply trying to get fresh eyes on the situation. Giving back sometimes means not saying the obvious to other adults. 
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
  • ethicalpaul
    ethicalpaul Member Posts: 5,611
    Thanks Charlie. It's true, more information keeps getting revealed as this goes on, but after hearing that this problem has been ongoing for 7 years, I don't think it's mansplaining to recommend getting a service contract with a dedicated HVAC contractor instead of whatever plumber has been unable to find the answer. But I'm just repeating myself now so I wish the OP good luck in solving this.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    Or she can talk to me a ..... Wait for it ..... A Plumber who fixes what the service contract brokers can't 
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
  • ethicalpaul
    ethicalpaul Member Posts: 5,611
    Plumber, HVAC company, tooth fairy, whatever, as long as they can fix it in fewer than 7 years! I don't hate plumbers :joy:
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • pedmec
    pedmec Member Posts: 932
    And this is why you shouldn't have a thermostat controlling a multi-unit apartment building. you need a master steam boiler control like a Heat-timer, Tekmar, or something similar. And not to **** on your plumber but if i took 7 seven years to figure out whats wrong with your system i don't think i would have a job.
    ethicalpaul