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.

Could my boiler be oversized?

Options
13

Comments

  • PC7060
    PC7060 Member Posts: 1,173
    edited January 2021
    Options
    underdog32 said: My understanding though is just re-stuccoing the outside alone would cost as much as a new boiler, if not more. Add in the moisture barrier and god knows how much foam board, and I'm sure it would be double the price. 
    ...Insulation would be a giant expensive job.
    Boiler replacement and insulation are two parts of the same problem: keeping the house warm at a reasonable price. Nice thing about insulation is you typically only pay for it once. 
    MilanD
  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    Options
    If a crossover trap is functioning properly -- and piped properly (that is the steam goes up, then over to the trap, and the outlet goes down to the dry return) -- there should be no condensate passing through -- and therefore the outlet should be only as warm as the trap body, and get cooler to match the dry return (which should be at least only just warm).

    Further, the steam main up to the trap should be steam hot, or close.

    If the outlet is really hot -- like steam hot -- steam is passing through the trap.

    Bucket traps don't really mind high pressures (well, within reason!) but it's important to remember that they need condensate in fair quantities to make them work -- and that they have no temperature seal. It is possible for them to pass quite a bit of steam under some conditions. Also, they have a lot of more or less loose parts in them -- so some rattling is to be expected.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • underdog32
    underdog32 Member Posts: 91
    Options

    If a crossover trap is functioning properly -- and piped properly (that is the steam goes up, then over to the trap, and the outlet goes down to the dry return) -- there should be no condensate passing through -- and therefore the outlet should be only as warm as the trap body, and get cooler to match the dry return (which should be at least only just warm).

    I assume you mean there should ONLY be condensate passing through, and not "no condensate"?
  • SlowYourRoll
    SlowYourRoll Member Posts: 187
    Options
    deyrup said:

    So that even though pressure increase ~1,600 times for each unit of water going from a liquid to a gas

    volume increases 1600 times, not pressure. if your boiler pressure ever increases 1600 times, you should probably exit the house asap ;)
  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    Options

    If a crossover trap is functioning properly -- and piped properly (that is the steam goes up, then over to the trap, and the outlet goes down to the dry return) -- there should be no condensate passing through -- and therefore the outlet should be only as warm as the trap body, and get cooler to match the dry return (which should be at least only just warm).

    I assume you mean there should ONLY be condensate passing through, and not "no condensate"?
    No, I meant exactly what I said. The purpose of the crossover trap is to exhaust air -- very quickly -- from the main into the dry return. Any condensate will be taken care of either by counterflow in the main (rare), a water seal loop (dubious) or connection of both the main and the dry return to a corresponding wet return.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • underdog32
    underdog32 Member Posts: 91
    Options

    If a crossover trap is functioning properly -- and piped properly (that is the steam goes up, then over to the trap, and the outlet goes down to the dry return) -- there should be no condensate passing through -- and therefore the outlet should be only as warm as the trap body, and get cooler to match the dry return (which should be at least only just warm).

    I assume you mean there should ONLY be condensate passing through, and not "no condensate"?
    No, I meant exactly what I said. The purpose of the crossover trap is to exhaust air -- very quickly -- from the main into the dry return. Any condensate will be taken care of either by counterflow in the main (rare), a water seal loop (dubious) or connection of both the main and the dry return to a corresponding wet return.
    I must be thinking of the wrong thing then. I was thinking those were the steam traps on the outlets of the radiators. I only have 3 f&t traps, 1 bucket trap, and those steam traps on my system.
  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    Options
    Ah. Well, F&T traps are a completely different critter. They do pass condensate, but require a fair amount elevation to do it -- or if you have pressure (you don't) you can arrange them to "pump" the condensate up some. They also can function as air vents. Sort of. That's not their purpose, and they really aren't much good at it.

    If you don't have crossovers, then you must have adequate venting on the mains, as well as adequate venting on the dry returns.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • underdog32
    underdog32 Member Posts: 91
    Options
    Based on the reaction I got from the guy at rj walker: "Gotta love it when people do strange stuff with boilers" when I showed him this, I'm going to assume it's wrong too.



    The picture in the manual shows this assembly is basically upside down. Also, the hole it's plugged into is hole "J", when it should be "I". I don't know how I would fit that assembly in upside down. It seems like it would bump into the sight glass, which is probably why it is the way it is, but I may try to move it to the proper hole.



    He also said "is this for a commercial building?", which I took to mean: "**** is with the size of that boiler?"

    I've seen posts asking about this boiler, and they're for 10k sf buildings, one is for a 8.5k sf building and he called it oversized for that.

    I changed that pressure guage which was reading -3 there, and still have not seen the new needle move when I ran a cycle.
  • acwagner
    acwagner Member Posts: 505
    Options
    What's the range of the new gauge you put on?
    Burnham IN5PVNI Boiler, Single Pipe with 290 EDR
    18 Ounce per Square Inch Gauge
    Time Delay Relay in Series with Thermostat
    Operating Pressure 0.3-0.5 Ounce per Square Inch

  • underdog32
    underdog32 Member Posts: 91
    Options
    acwagner said:

    What's the range of the new gauge you put on?

    It's a 30 to satisfy code. They didn't have anything lower to add on. I have to order the low pressure gauge.
  • underdog32
    underdog32 Member Posts: 91
    Options
    I think I can confirm that the system is not operating on higher pressure than it should be. I installed the new gauge today and it did raise to 1, but did not go over 1. I watched it for an hour while the system heated from 69-74 and eventually shut of on temp. I set it to 74 to force it to run as long as possible. After that hour, every radiator in the house was fully hot, so they all heated appropriately.

    The water level in the sight glass slowly rises and falls consistently.

    ALL the dry returns are hot, and I'm assuming it's a normal amount of hotness. I can grab them, and hold my hand there for a second or two before it gets too uncomfortable, unlike the supply lines that I can only touch for an instant. So I think those are all ok and I'm not losing steam in the returns.

    Aside from fixing those header pipes, I think the only thing left for me to try is skimming the boiler.

    If my office was 3 degrees warmer I'd give up on this thing at this point.

    All the math checks out to support my conclusion that the darn thing is just too big and that there isn't really anything left that is wrong with the system.

    When running the forced air, i use a consistent .6ccf/h to match the 60k btu input.

    When running the boiler, I use a consistent 5ccf/h to match the 520k btu input.

    I think the only way to reduce the cost is to either reduce the input, or reduce the amount of time that it runs. Considering that the run time matches my forced air runtime pretty closely, I'm thinking that the runtime is appropriate, which means it's costing exactly how much it's supposed to cost and doing exactly what it is supposed to do.

    I wonder if there is anything I can do outside of replacing the boiler though?

    Could I (I being a professional I hire) do something like change the firing system with a lower peerless 62 model's system? I don't know how these things work, but the manual looks like the systems are all pretty much the same, but use different water capacity/mbth input. If I could drop down a model or two then maybe it would be enough to make it affordable, or is that not how it works?
  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    Options
    Something simply doesn't add up. You have a steam boiler burning enough gas to generate 520,000 BTUh. You have a warm air furnace burning enough gas to generate 60,000 BTUh. You claim that the latter is sufficient to heat the structure -- which I don't doubt, give or take. So. We somehow have to account for 460,000 BTUh.

    I can assure you -- with no hedging -- that something is seriously wrong -- not with the boiler; even the worst of the worst of the old coal conversions were much more efficient than that (though some of them did get down around 50%!).

    You have asserted that it has to be the boiler and, so far as I can tell, not questioned the numbers. I will say again -- you are shooting the messenger. Something -- and there's no way for me tell what, though I'd love to help you -- is very seriously wrong here, but so long as you focus solely on the boiler, you're never going to figure out what.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • acwagner
    acwagner Member Posts: 505
    edited January 2021
    Options
    If you're that oversized, running a 5 degree temp increase should have cycled on pressure. Multiple times. Either that or you have a hole in the boiler and steam is going up the chimney--but you said you don't have any water loss.

    Have you made sure the assembly that the p-trol and pressure gauge is on it clear all the way into the boiler? It could be clogged and not reading the boiler pressure. You might want to pull that whole thing off to check.

    Is there a detached garage or some other building that the boiler services that the forced air doesn't?
    Burnham IN5PVNI Boiler, Single Pipe with 290 EDR
    18 Ounce per Square Inch Gauge
    Time Delay Relay in Series with Thermostat
    Operating Pressure 0.3-0.5 Ounce per Square Inch

  • underdog32
    underdog32 Member Posts: 91
    Options
    I pulled the pressure gauge off, overfilled the boiler and let the water flush the line until it ran clear. It was gunky at first.

    Would pressure build up if the venting was adequate to accommodate the steam flowing?

    I do think the steam moves slowly. I feel like it should heat up faster, but everything did heat up eventually.

    Like I said, I only have 2 remaining things to try:
    1) skim it
    2) fix the header piping

    After that, I'm out of ideas. My only current theory is that I'm losing a bunch of heat to wet steam condensing early, but even in the best case scenario, what would I realistically expect to change? My cycles will go from 24 minutes to 10 minutes? If it were running for 20 hours a day then there would be a lot of room for improvement, but it's 6-8, and that seems reasonable.

    @Jamie Hall What else can I do? I've done every single thing I can think of (other than those last 2 things), but the messenger keeps delivering the same message.

    I don't want to buy a new boiler, trust me. The only thing I want is affordable heat.

    Also, its 3 separate 60k furnaces with a combined output of 180k, not a single 60k.

  • acwagner
    acwagner Member Posts: 505
    Options
    Are all the burner tubes ignited when it fires? Maybe the gas is flowing to the boiler but not all of it is being burnt.
    Burnham IN5PVNI Boiler, Single Pipe with 290 EDR
    18 Ounce per Square Inch Gauge
    Time Delay Relay in Series with Thermostat
    Operating Pressure 0.3-0.5 Ounce per Square Inch

  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    Options
    Well, three 60 K makes a little more sense than one. But... you still have to account for 340 K or so BTUh which are... vanishing. Into thin air, it would seem.

    The wet steam is vaguely attractive, but I would point out that if you are condensing that much steam somewhere in the header or mains, they are going to be HOT. You don't have the surface area to do that. That much heat requires about 1,333 square feet of effective radiation to condense, assuming air as the condensing medium.

    Frankly, I think that at this point you need to get new eyes on. Get a really competent technician, with the proper instruments, to ensure that the burner is adjusted properly. Measure gas input, directly if possible. Measure stack temperature. Determine stack gas composition -- at the very least, oxygen, carbon dioxide and carbon monoxide. Those numbers and a little figuring, which the tech. can do, will give you actual real world boiler efficiency.

    That, and the gas flow, will give you the real world rate at which steam is being created by the boiler. The actual total EDR of your system will give you the real world rate at which steam can be condensed by the system.

    Put an accurate pressure gauge on the system. Perhaps two of them -- one 0 to 5 psi, and one 0 to 30 psi. Why, because any excess of the steam creation rate minus the steam condensation rate can only go to one of two places: compression of the steam, or a leak. Compression will show up as a pressure change (though, since this is saturated steam which is anything but an ideal gas, not as much as you might expect). A leak, of course, should show up somewhere -- if we assume that all of that difference is going into a leak, that's on the order of 9,000 cfm of steam. Which you would notice...

    At the moment, the numbers just don't add -- and we need to get them to add.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • kenlmad
    kenlmad Member Posts: 56
    Options

    With the controls connected "upside down", I don't see a water seal between the pressure controls and the boiler. How quickly do these items "cook" to death without one? Maybe these units are damaged due to the improper installation and are confounding your troubleshooting.
  • AdmiralYoda
    AdmiralYoda Member Posts: 632
    Options
    My boiler is 40% oversized and I cycle on pressure (1.5psi) in 10-15 minutes depending how hot the water is in the boiler.

    Get a Kodiak Controls KC25-3# 0-3psi from Amazon.  It's a good gauge and it's cheap.

    If a boiler that oversized was installed in my house it would probably start cycling before the radiators even got warm.
    BobC
  • underdog32
    underdog32 Member Posts: 91
    Options
    This was about 75% "this isn't too bad" 25% "why did i start this" and 10% "i wish i was better at measuring", but it's done. critique?

    If i did want to replace the boiler, is the header piping something that is generally reused, or do they redo it all?


  • acwagner
    acwagner Member Posts: 505
    Options
    Well, you're a true DIY god for taking a project on like that in January. It looks good for what you got to work with.

    I think in your situation if and when the new boiler is put in the header will be redone. The new boiler will obviously be physically smaller, so working with what's there might not be the easiest. Although, I'm a homeowner so I imagine the Pros here will have better input on that.
    Burnham IN5PVNI Boiler, Single Pipe with 290 EDR
    18 Ounce per Square Inch Gauge
    Time Delay Relay in Series with Thermostat
    Operating Pressure 0.3-0.5 Ounce per Square Inch

  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    Options
    I'll second that comment on the work -- nice job! As to reuse, the short answer is... sometimes.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • ethicalpaul
    ethicalpaul Member Posts: 5,729
    edited January 2021
    Options
    Omg well done, I’m shocked

    Edit: not shocked that you did well—but shocked at how well you did to fix the order issue
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • Zipper13
    Zipper13 Member Posts: 229
    Options
    I've said this in a few other threads in here recently, but I've seen the light and have to spread the word!

    Are the steam lines insulated?
    This doesn't get at your question about boiler size (I'm not qualified for that) but it may impact fuel use for you.

    I added insulation to the steam lines this fall and as COVID has us working from home, we've raised the thermostat few degrees vs last year. Yet, comparing last year's fuel use per heating degree day, we're using less fuel now and with more regular on times (about 20 minutes on every 2 hours so far this year vs. all kind of crazy intervals last year ).

    I want to say the material cost to insulate the steam pipes was around $2.75/ft delivered.
    New owner of a 1920s home with steam heat north of Boston.
    Just trying to learn what I can do myself and what I just shouldn't touch
  • underdog32
    underdog32 Member Posts: 91
    Options
    Zipper13 said:

    I've said this in a few other threads in here recently, but I've seen the light and have to spread the word!

    Are the steam lines insulated?
    This doesn't get at your question about boiler size (I'm not qualified for that) but it may impact fuel use for you.

    I added insulation to the steam lines this fall and as COVID has us working from home, we've raised the thermostat few degrees vs last year. Yet, comparing last year's fuel use per heating degree day, we're using less fuel now and with more regular on times (about 20 minutes on every 2 hours so far this year vs. all kind of crazy intervals last year ).

    I want to say the material cost to insulate the steam pipes was around $2.75/ft delivered.

    Everything in the house except what you see in that picture has been insulated. I have the insulation for that header, but I haven't put it on yet.

    Sadly this header repipe didn't really yield any savings. It's running pretty much the same as it was before which is disappointing.

    I'm going to finish insulating and skim the boiler this weekend and see if that does any good. After that the plan is boiler off and I'll live with the forced air until I can afford to do something about the boiler.

    I will say that every time I come across a post casually mentioning > 400kbtu boilers, they are ALWAYS talking about 10k+ square footage buildings, or 4+ family apartment buildings. This thing is definitely more than I need. I'll run it a few times a year to keep it from just sitting, but I can't use it as my primary heat as it is.
  • acwagner
    acwagner Member Posts: 505
    Options
    @underdog32 I would still have someone look at the burners on your current boiler. It just doesn't add up, at least with the information we have. It's possible the boiler isn't fully burning the gas coming in for some reason.
    Burnham IN5PVNI Boiler, Single Pipe with 290 EDR
    18 Ounce per Square Inch Gauge
    Time Delay Relay in Series with Thermostat
    Operating Pressure 0.3-0.5 Ounce per Square Inch

  • kenlmad
    kenlmad Member Posts: 56
    Options
    To the experts out there: Isn't the lack of a pigtail or any type of water seal for the the pressure controls an issue? Honeywell has a max rating on these controls of 150 deg F. His controls are plumbed directly to steam.
  • underdog32
    underdog32 Member Posts: 91
    Options
    acwagner said:

    @underdog32 I would still have someone look at the burners on your current boiler. It just doesn't add up, at least with the information we have. It's possible the boiler isn't fully burning the gas coming in for some reason.

    You know, I don't know anything about that, but I'm going to go off the assumption that this guy put this boiler in himself, and he may not have known anything about that either. If he just hooked up all the pipes and stuff and turned it on, would it fire?

    Who would be the right type of professional to investigate that? I'm guessing I need a steam specific type person, but apparently I am in a dead zone for find a contractor. Not sure who I could trust locally.
  • acwagner
    acwagner Member Posts: 505
    edited January 2021
    Options
    I'm not a pro, but any burner system should be tested after it's hooked up to make sure it's getting complete combustion (a combustion analysis), exhausting properly, the gas inlet pressure is set correctly, all the burner tubes are igniting, etc. I would think any decent HVAC tech should be able to check the burner for you. You wouldn't need a steam specific person for that.

    Do all the burner tubes ignite? That would be the first thing to look at. All the other stuff would need a professional with the right equipment.
    Burnham IN5PVNI Boiler, Single Pipe with 290 EDR
    18 Ounce per Square Inch Gauge
    Time Delay Relay in Series with Thermostat
    Operating Pressure 0.3-0.5 Ounce per Square Inch

  • underdog32
    underdog32 Member Posts: 91
    Options
    tomorrow after I skim it I'll run a test run and pay extra attention to the tubes. They all look like they fire, but I haven't really looked yet. I just glance down to see if it's glowing to verify it's on.
  • MilanD
    MilanD Member Posts: 1,160
    edited January 2021
    Options
    Ok, I'm late to this thread but here's my 2 cents.

    You said you ran your 3 furnaces over a 9h period for 3+3+1 hours, at 62kbtu input each (or was it 69kbtu). That's about 434-483 kbtus that kept you comfy. You also said that on a similar day your boiler runs 20 min/hour. Over 9 hours, that's 180 min, 3 h, at 520kbtu for a total input of 1560 btus. Did I get this close enough?

    Your boiler btus are staying in the basement and/or going up the chimney. Typical for an oversized boiler.

    Heating systems are not space shuttles. On a steam set up, heat loss of the building is marched by the rad output edr, which is to be matched by the boiler output edr. Too much edr at the boiler = quick pressure rise at the boiler, as there is not enough system (rad) capacity to take it up, to distribute and dissipate all that btu from the boiler. What you are seeing is a result of the oversized boiler, plain and simple, and your furnace test proved this. 434-483kbtu input is all that you needed to keep the place comfy on that given day with the furnaces you have. I'm ignoring output efficiencies as we are looking at fuel input.

    So, my bet is that your op pressure is waaaay too high if your boiler is not cycling and is burning 20 min straight. Your heat is staying in the basement and going up the chimney. High pressure will also slow down the steam, to your point 4. above, on rads not being hot, and will also make your bucket trap gurgle. 

    Your only salvation may be figuring out how to run the system in a vacuum, to allow for drawing of steam from that large water chest at lower temps and the burners off... Or to add more radiators. Otherwise, unless you replace the boiler to more closely match the edr and pipe it in to spec, you are doing all that you can with what you got and kudos on all the maintenance done so far. Btw, I don't think repiping that colliding header will improve things much... Boiler is just too big.

    (Edit): Last thought, and this is theoretical. You may be abale to direct vent this thing and then down fire it. This should allow you to regulate o2 and co through tuning the draft to match the down firing. That being said, you probably won't find anyone willing to do this for the obvious legal risks one would assume if attempting something no one is doing as a standard practice. And, it'll cost the time and supplies to do it.

    One more thing, convectors on steam, imho, are not that great. You get no thermal mass and latent radiation once the boiler is off. This makes the rooms feel colder and requires boiler run more often, even the appropriately seized one. I'd keep that in mind as you're dumping money and effort at it.

  • underdog32
    underdog32 Member Posts: 91
    Options
    MilanD said:

    Ok, I'm late to this thread but here's my 2 cents.

    You said you ran your 3 furnaces over a 9h period for 3+3+1 hours, at 62kbtu input each (or was it 69kbtu). That's about 434-483 kbtus that kept you comfy. You also said that on a similar day your boiler runs 20 min/hour. Over 9 hours, that's 180 min, 3 h, at 520kbtu for a total input of 1560 btus. Did I get this close enough?

    Your boiler btus are staying in the basement and/or going up the chimney. Typical for an oversized boiler.

    Heating systems are not space shuttles. On a steam set up, heat loss of the building is marched by the rad output edr, which is to be matched by the boiler output edr. Too much edr at the boiler = quick pressure rise at the boiler, as there is not enough system (rad) capacity to take it up, to distribute and dissipate all that btu from the boiler. What you are seeing is a result of the oversized boiler, plain and simple, and your furnace test proved this. 434-483kbtu input is all that you needed to keep the place comfy on that given day with the furnaces you have. I'm ignoring output efficiencies as we are looking at fuel input.

    So, my bet is that your op pressure is waaaay too high if your boiler is not cycling and is burning 20 min straight. Your heat is staying in the basement and going up the chimney. High pressure will also slow down the steam, to your point 4. above, on rads not being hot, and will also make your bucket trap gurgle. 

    Your only salvation may be figuring out how to run the system in a vacuum, to allow for drawing of steam from that large water chest at lower temps and the burners off... Or to add more radiators. Otherwise, unless you replace the boiler to more closely match the edr and pipe it in to spec, you are doing all that you can with what you got and kudos on all the maintenance done so far. Btw, I don't think repiping that colliding header will improve things much... Boiler is just too big.

    (Edit): Last thought, and this is theoretical. You may be abale to direct vent this thing and then down fire it. This should allow you to regulate o2 and co through tuning the draft to match the down firing. That being said, you probably won't find anyone willing to do this for the obvious legal risks one would assume if attempting something no one is doing as a standard practice. And, it'll cost the time and supplies to do it.

    One more thing, convectors on steam, imho, are not that great. You get no thermal mass and latent radiation once the boiler is off. This makes the rooms feel colder and requires boiler run more often, even the appropriately seized one. I'd keep that in mind as you're dumping money and effort at it.

    My basement is definitely warm when the boiler is running. The entire basement (probably at least 1k sf) is as warm as or warmer than the house. My wife sees it as a feature since she has a room set up down there to do preschool with the kids.

    Thanks for your thoughts. I'm more or less on the same page now. i believe that the boiler is just using the gas it needs to to run, and that happens to be a lot. I'm doing everything I can think of to improve the situation, and the changes produce minimal if any improvement. I'll probably get someone out to look at the burners just in case.

    After the skim I'm going to run it for 2 days or so and get a good test of it running hot for a couple of days and see if it got any better at all.

    The only confusing things are that I'm NOT seeing high pressure, or any pressure at all really. No knocking or banging or anything like that. It all seems to be running smoothly aside from the high gas cost. I'm wondering if they already downfired the boiler or something. I'm also going to look for stickers from an installer today to try to determine if it was installed by a pro and inspected or not. I've not seen any yet.
  • underdog32
    underdog32 Member Posts: 91
    Options
    No marks on the boiler from an installer or inspector. There is a sticker on the water feeder from a plumber dated 1999, so a plumber probably did that at least.

    Fired it real quick to test the tubes. They all look good. It's like a sea of flame under there.

    The auto igniter control board (i think that's what it is) makes a constant click buzz noise when the boiler is not firing, but ignites the boiler immediately when heat is called for, and then the noise stops.
  • MilanD
    MilanD Member Posts: 1,160
    edited January 2021
    Options
    The only confusing things are that I'm NOT seeing high pressure, or any pressure at all really. No knocking or banging or anything like that. It all seems to be running smoothly aside from the high gas cost. I'm wondering if they already downfired the boiler or something. 
    @underdog32

    This is confusing to meet too, the apparent lack of pressure buildup. When you cleaned the control tree, did you unscrew it all the way to the boiler? Did you blow in it and your breath freely entered the boiler?

     And you said you're not adding water at all? Do you have a vxt on it, or a meter, or is it manual feed only?

    All this makes no sense. As pointed out earlier, that gas energy burned has to be transferred somewhere and it makes no sense that 3 furnaces at the combined 180kbtu would be enough to keep you comfy, as the 520kbtu boiler, and would take same amout of time, yet without any excessive energy losses on the boiler. It just doesn't add up...

    My house is brick, uninsulated, 2400sq ft, and the furnace is 120 btu input 112 btu output with no issues holding temps at 0 degree design temp and say 20F outside. 

    As to the boiler being downfired, you'd see it reflected in your bill. Out of curiosity, you can clock the meter and see exactly. But you're probably right with all your calculations so far. For all you know, the heat is likely just staying in the basement. But again, how is the boiler not building any pressure? It just doesn't add up.... A head scratcher for sure.
  • kenlmad
    kenlmad Member Posts: 56
    edited January 2021
    Options



    The only confusing things are that I'm NOT seeing high pressure, or any pressure at all really.

    @underdog32
    What gauge are you using to read pressure? Maybe it's already been said earlier, the 30 PSI gauge on the boiler cannot be trusted. They are notoriously incapable of reading low (or any) pressure accurately. Your next investment should be a new low pressure gauge (3 PSI preferred, 5 PSI max) and a pigtail so that the controls and gauge are not plumbed directly into the steam. Only then will you know the pressure in the boiler. After that you can then figure out if the Vaporstat and Pressuretrol are working correctly or if they are damaged from the years of direct connection to the steam. Good luck.
  • underdog32
    underdog32 Member Posts: 91
    Options
    kenlmad said:



    The only confusing things are that I'm NOT seeing high pressure, or any pressure at all really.

    @underdog32
    What gauge are you using to read pressure? Maybe it's already been said earlier, the 30 PSI gauge on the boiler cannot be trusted. They are notoriously incapable of reading low (or any) pressure accurately. Your next investment should be a new low pressure gauge (3 PSI preferred, 5 PSI max) and a pigtail so that the controls and gauge are not plumbed directly into the steam. Only then will you know the pressure in the boiler. After that you can then figure out if the Vaporstat and Pressuretrol are working correctly or if they are damaged from the years of direct connection to the steam. Good luck.
    I am using the 30psi guage, a new one that i installed. When I pulled the guage off to replace it, I filled the boiler to the point where water came out of that pipe, and pipe cleaned it until it ran clear. I believe it is open. It is upside down, and I am curious as to the answer to your question about how that would affect it.

    I actually bought pigtails for all of those controls, BUT I looked in the manual and aside from being upside down, it looks exactly right:



    It would be trivial to reverse the orientation so it matches that, but it would then have to be at an angle because it would bump into the sight glass otherwise.

    I'll say that the 3 furnaces at 180k btu keep us warm enough, but the radiators definitely do a better job. I am not losing any amount of water than I can tell. I can hear the water feeder running in my living room if it kicks on because it's right below the return vent, and I do not hear it running. I heard it once since I fixed that bucket trap.

    I wish I knew why things didn't add up. I agree completely, but I'm not making any of this up. I just watched a whole cycle from 67 to 70 and the pressure gauge didn't move the whole time. I wonder how long I'd have to run it to see the gauge move at all. This cycle lasted 29 minutes. During the cycle, the sight glass bobs up and down less than an inch peacefully about once per second.

    I just skimmed it until it ran clear, flushed it until it ran clear and ran a cycle. Then filled the water line to exactly 22.5 inches as the manual says.

    I do wonder if I maybe need a vent here:



    From what I can tell, two mains from the boiler meet here. There is an f&t trap right there that drops into my wet return so I think the air has an escape, but the main on the right fills kind of slow in my opinion.
  • MilanD
    MilanD Member Posts: 1,160
    edited January 2021
    Options
    From everything you just said, here's my 2nd opinion:

    1. You not hearing the water makeup coming on does not mean it's not. The only way to know is to have a meter on it. It could happen when you're sleeping, not at home, etc. You can check for the boiler soundness by flooding a lukewarm or cold boiler and look for leaks under it. Also, if you stick your head under the went hood briefly while the boiler is running (hold your breath), if the boiler is rusted and sending steam up the chimney, you'll hear a sound similar to water running through a main, or like the toilet water tank while it's filling up.

    2. The control tree setup matters. Pictured in the manual creates a "p" trap with the pipes going out of the boiler-down-right-up. Like a piped pigtail. Your current setup does not have a trap and allows direct contact of the steam and the preasuretrol bladder/element which, for all you know, may have fried both controls, which then means the only safety you have is your 15 psi prv. I would definitely install the pigtail. You don't want to find out what it sounds like when the prv does its job and blows of 15 psi through a 1" pipe. You'll need new underwear...

    3. 30psi pressure gauge, howevermuch new, will NOT measure accurately anything below, oh, 15psi, and is nothing more than a decoration for low pressure steam system. This means that you could be pumping as much as 10 psi and not know it, with the exception of blown traps, be it f&t or bucket, and perhaps super noisy air vents.

    There can't be missing energy. It's going somewhere, and the question is if it's up the chimney, staying in the basement making it really really cozy, or a combo of the two. Also, not cycling on pressure makes no logical sense, no matter how you look at it. That 520kbtus input x 0.80 (minus 33% pickup factor) attached to half that in edr in rads is going somewhere.
  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    Options
    Actually, an F&T does function as a vent, up to a point. Not a very good one, but it does.

    However, I'll say it again -- your basic, fundamental numbers simply don't add up. That's not a problem with the boiler being one size or another. There is somewhere in the vicinity of 400,000 BTUh which is simply unaccounted for by the numbers I've seen here. If we make the somewhat bizarre assumption that somehow that boiler is so bad that it's all going up the chimney in the flue gasses, we're looking at somewhere around 1,200 cfm of 1,500 degree Fahrenheit gas -- which, I think, would be noticeable.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • kenlmad
    kenlmad Member Posts: 56
    Options
    Hi underdog32.

    The pipes being "upside down" is exactly the problem. When the boiler starts steaming and the water in the boiler drops to the redline on the image below you will lose the protective water seal when all the water in the pipes drains into the boiler (blue arrows).

    If it installed properly like in the Figure 22, all the water below the first 3/4" cross stays in the pipes to form a water seal regardless of the water level in the boiler. This is kind of important.

    acwagner
  • underdog32
    underdog32 Member Posts: 91
    Options

    Actually, an F&T does function as a vent, up to a point. Not a very good one, but it does.

    However, I'll say it again -- your basic, fundamental numbers simply don't add up. That's not a problem with the boiler being one size or another. There is somewhere in the vicinity of 400,000 BTUh which is simply unaccounted for by the numbers I've seen here. If we make the somewhat bizarre assumption that somehow that boiler is so bad that it's all going up the chimney in the flue gasses, we're looking at somewhere around 1,200 cfm of 1,500 degree Fahrenheit gas -- which, I think, would be noticeable.

    Here is my amateur explanation for that, backed by zero qualifications and a degree in nothing:

    So my understanding is that EDR is what creates the output BTU that fills my house. The EDR->BTU that I measured was something like 100k, I don't remember exactly, but lets go with the 180k that the furnaces use.

    The boiler input is 520kbtu, meaning that's what it costs to fire, regardless of the connected load. The boiler my very well be producing 520k*.8 btu output to boil the water, because that's what it costs to boil 35 gallons of water to steam. Then that steam goes to my pipes and heats everything mostly until the house is the set temperature, but regardless of how much it cost to heat the water, the radiators are only kicking out their EDR worth of BTU. Once the house reaches temp, and the boiler shuts off, I have 35 gallons of 211 degree water sitting around that was heated for nothing because it's latent heat wasn't needed. So the boiler now has a crap ton of hot water in it that is NOT in my radiators, and NOT in my house, and NOT in my shower. So, 1.5 hours go by before it needs heat again and we start again. We heat up 35 gallons of water to steam again and fill the radiators over 25 minutes.

    I think we're trying to equate the 500kbtu with the heat that ends up in the house, but it's not really. It's the heat that ends up in the water. The radiators can only produce their rated output, regardless of input. Steam doesn't get hotter because of the size of the boiler, there is just more of the same temperature steam.

    I am as baffled as everyone else about why pressure doesn't build. I will reverse those controls and buy a low pressure gauge and see if I see anything, but for pressure to be a problem both of my pressuretrols would have to be broken. That's probably not impossible, but is it likely? How to test them?
  • kenlmad
    kenlmad Member Posts: 56
    edited January 2021
    Options