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Boiler isn't heating regularly

adambnycadambnyc Member Posts: 260
Hey all,

Got a call from mom last night. Her downstairs tenant is a peice of work and complains that he isn't getting heat. Might be BS, not sure.

I'll get more info and pics but tenant is on his own hot water boiler. When I took a look at it, stack was hot and circ pump was hot. Tenant claims that at random times the boiler stops working.

Mom had a plumber in who told her she needed a new heat exchanger, but manually lit the pilot light just to get the boiler back on. That's a real head scratcher of a statement to me.

Is the red light on the box indicative of a problem? What other details should I gather to help troubleshoot?


  • Leon82Leon82 Member Posts: 655
    The red light is on when the tstat calls for heat. The pump should run when the light is red
  • adambnycadambnyc Member Posts: 260
    Thanks Leon. What if the red light never goes off?
  • Tim McElwainTim McElwain Member Posts: 4,357
    That says the relay is powered all the time and the circulator would probably run constantly. What kind of gas control system is on this equipment, we need more information?
  • heatheadheathead Member Posts: 96
    Looks like the circulator is mounted in the wrong position.
  • adambnycadambnyc Member Posts: 260
    is the circulator upside down? I'm working on more pictures and information. Mom is in Brooklyn, im in NJ. Thanks for the focus
  • Leon82Leon82 Member Posts: 655
    Usually they want the motor horizontal. The red light should go off once the tstat is satisfied and opens the circut
  • GordyGordy Member Posts: 9,523
    What kind of heat emitters? Are they warm/hot?

    Boiler, and piping pics would be great. Yes the pump should have the motor horizontal. The way it is mounted now can trap air.

    Check tridictator on the boiler also to see what system pressure is.
  • adambnycadambnyc Member Posts: 260
    Interesting. I wonder if the pump is failing or has air trapped in it. That would keep the system "running" and probably keep the pump hot to the touch also.

    If I remove the pump, will the system drain? There are no air bleeders on any of the baseboards. I'm thinking I should install some hose bibs and run the city pressure thru the line to clear out any air.

    Still working on the additional info.
  • Leon82Leon82 Member Posts: 655
    There may be ball valves or flange valves on each side you can close. You can feel the pipes(carefully) to see if the return is coming back hot. It it stays cold you know where to start looking
  • adambnycadambnyc Member Posts: 260
    Finally got back there. A number of things are concerning me. The red light NEVER turns off. The pump never turns off. I can't find the thermostats wire anywhere. Also, I believe this boiler was converted from steam.

    Something I'm not sure is incorrect, but seems wrong to me. The pump is actually pushing water into the bottom of the boiler and forcing hot water out the top and into the loop. This just doesn't sound right to me.
  • JUGHNEJUGHNE Member Posts: 6,783
    edited November 2016
    Looks like all the parts are there, but not installed very well.
    Don't kick that stick out from under the pipe going to the exp tank.

    That is a lot of boiler for perhaps a small apartment??
    Looks like 3/4" copper in and out of the boiler.
    With pump not doing its job, the high limit could shut the boiler down for quite a while causing intermittent heating.
    The horizontal exhaust flue piping looks to be running down hill to the chimney.....not good.
    I didn't see any means to drain the boiler at all, Holding open the pressure relief valve (don't do this all the time) would drain down the system to that level. There would still be some water from opening the flanges on the pump.

    I think the whole thing needs help from a pro.

    PS: If you move this whole thing to the Main Wall it might get more views?
    Also, if a boiler like this is still holding water how could it need a new "Heat exchanger"?
  • adambnycadambnyc Member Posts: 260
    edited November 2016
    Yes, this boiler is for the Downstairs aparatment, mom has steam heat (IN6) for her apartment upstairs. I'm not sure how to move the thread to the main wall.

    Also, I didn't snap a picture of the right side of the boiler, there is a drain on that side.
  • neilcneilc Member Posts: 805
    that picture of the burner tubes,
    looks like one isn't seated properly,
    not that this is causing a intermittent heat,
    but does say a pro should have a look see.
  • Leon82Leon82 Member Posts: 655
    There is a chance that the tenant turned the thermostat all the way up which would cause it to constantly run.

    They don't seem to understand that it doesn't heat faster if the number is turned up
  • JUGHNEJUGHNE Member Posts: 6,783
    Tenants will do these things, especially if they don't pay the gas bill.
    So assume that happened, can that pump push enough water thru that 100,000+ boiler with 3/4" piping to keep it from hitting high limit? Someone here knows that off the top of their head, for me it is just a gut feeling it won't flow. (All the info is here in my office but I don't want to look it up).
    Then it goes off on high limit, cools down and starts over, etc.
    Just another WAG.

    But if my Mom lived above this boiler, I would give it some attention. Even if the least dangerous event took place..... the stick holding up the exp tank fell down.....breaking off the copper out of that tee.....water fill valve on and running forever. This floods the basement, tenant eventually notices it, calls someone, hours later the water gets shut off, mold starts immediately, tenant coughs, locates attorney, sues etc.

    ......And you know I have never sold insurance in my life, but maybe I missed that vocation...... ;)

    IIWM, I would get a trusted pro in there. I noticed you are pretty handy yourself and could learn a new trade.
  • Danny ScullyDanny Scully Member Posts: 1,221
    edited November 2016
    Not that this helps, but just so you know, that's a steam boiler. Obviously it can be used for forced hot water as well, but it clearly was used as a steam boiler once.
  • adambnycadambnyc Member Posts: 260
    Thanks all. Still looking for answers. I think it's pretty obvious that the boiler is wired up wrong.

    How about the pump. I know it's upside down, but should it be pushing water into the boiler from the bottom and forcing hot water from the top to the rads? Seems backwards to me.
  • STEVEusaPASTEVEusaPA Member Posts: 4,103
    edited November 2016
    You can pump into the boiler, it's not entirely wrong, but there is plenty there that is wrong.
    If I were there, the first thing I would do is remove t-t from the relay and see if the relay shuts off. If it does then I would start ohming out the t-stat wires to see if they aren't shorted out.
    If this boiler keeps running and never hits high limit, then you have at best a perfectly sized boiler and at worst an undersized boiler. But if that were the case, this wouldn't be the first time you would hear about under heating. A large volume system will take a long time to heat all that water.
    You just have to be diligent, ask a lot of question, and try to understand where all the pipes go.
    Maybe the tenant has valves closed in his unit, or the rads need to be bled.

    ~~start of story~~
    2 days ago I get a call for no heat on one side of a 5 unit building. No one can figure it out. They bled radiators, checked everything, etc. etc. I look at the boiler and see 2 relays. I say, where's the thermostat for this side of the building. Landlord says there isn't a thermostat-never was, tenant says there isn't a thermostat (there has to be a thermostat, I see thermostat wire on a relay). I asked, when was the last time you had heat. She said she just moved in last month, after they completely remodeled her apartment, but she has no thermostat (Aha!). So I go and investigate, CSI style. I guess at a couple of places where I would put a thermostat, and find a drywall patch. Cut open a small hole, look inside, find the thermostat wire. Very lucky. Must be some kind of Karma for the many times it went the other way. Put on a new thermostat, tenant has heat.
    ~~end of story~~
    The moral to my long-winded story is: it probably worked at one time, keep asking questions/investigating until you figure it out. And don't be afraid to bring in help.
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