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Boiler Sight Glass Always Full - Even after service and skim - need new ideas to investigate!

seandempsey
seandempsey Member Posts: 28
edited February 2023 in Strictly Steam
Hello everyone, let's see if I can be real concise:

Recently, my boiler sight glass has been totally full, even when I do the blowdown regularly during the heating season (Bangor, ME). Normally, the sight glass will lower as the water is released, then the auto-filler groans and fills things back up, and that has kept the water level at the mark indicated with the sharpie on the boiler, which is above the DWH coil but below the pigtail for the pressure limiter.

I had a boiler serviceperson come by and they showed me how to do a skim and we got the water level back to the spot indicated with the sharpie. This stayed where it was for a few days, but now the glass is back to being full.

In my pictures, he told me that valve A is what is going into the auto feeder, and I can close it during the blowdown. Normally I didn't close it. So I just took out about 3 bucketfulls, which is reckon is about 6 gallons, and the water level in the sight glass bobbed down maybe an inch, but it just fills right back up. I don't know how many gallons of water should be in there, but without knowing how to manually refill it if I drain too much, I don't want to go too crazy.

The tech did mention, I think, that Valve B in the picture is normally closed but if I open it, it would send water into the boiler and bypass the autofiller, but I haven't tried that as I already think I have too much water.

So at this point, I am not sure what my next step of investigation and remediation are. I can call the boiler guy again, but I would also like to get to know what I am doing a little more myself, this seems like something I should know how to do.

Also, you can see that the valves that close the ends of the sight glass are both either missing or busted off. Probably something I want to replace.

A few more data points:
- the heating is working, though sometimes it seemed slow (related to the next bullet)
- The technician explained the "steam chest" at the top where the steam builds up, and that if it's full of water, the water boils slower, but also has less room for the steam to form (just repeating what I remember, this is a new concept to me). Maybe this is why it is slow to heat, or it's not slow and I am imagining it.
- I want the water level above the DHW coil, but below the pressure trip shutoff: though right now, the sight glass level is above where the pigtail goes to the shutoff, so no idea if that is right or not.

I am at the edge of my current knowledge; happy to acquire more! Where should I be investigating next to diagnose this and either remediate it, or give the technician better info?

I await your responses!







Comments

  • kcopp
    kcopp Member Posts: 4,418
    Have you cleaned out the fittings to the boiler sight glass? Not uncommon for them to get plugged up.
  • Waher
    Waher Member Posts: 245
    edited February 2023
    Does your pressure gauge always read close to 10psi? Your pressuretrol looks like it set for less cut-out pressure than that which may indicate the gauge is faulty, your pressretrol is faulty, or your pigtail is clogged. The boiler not operating properly could be the reason your water levels in the sight glass are off, or the sight glass may be not working properly, or the autofiller may be not working properly. You have many things going on simultaneously which aren't right which have to be eliminated to narrow down where the problem lies.

    The tech should never have left your property without forcing you to replace the sight glass valves. That's not a safe operating condition.
  • Jamie Hall
    Jamie Hall Member Posts: 23,164
    First of all. Ir looks like valve C is on the pipe to the pressure relief valve. This is extremely dangerous, as if that valve gets closed for some reason you no longer have a pressure relief. Turn off the boiler and leave it off until you can get that valve removed.

    Now,whatever else is going on -- and I think there are a number of things -- the fact that the sight glass does not seem to accurately show the water level in the boiler is flat out dangerous. Before you panic, check it is possible to drain water from the boiler and if the level in the sight glass reflects that draining. You will need to close whatever valve or valves that can feed water to the boiler to do this. Then open whatever valve you use to manually feed and try adding water. The sight glass should respond.

    If the sight glass doesn't respond to that treatment, again you have a completely unsafe condition. Turn off the boiler and leave it off until you can get it fixed.

    Now you can set about figuring out what other problems you have and fixing them.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Waher
  • 109A_5
    109A_5 Member Posts: 1,377
    edited February 2023
    Hello @seandempsey,

    First of all. Ir looks like valve C is on the pipe to the pressure relief valve.

    Looks to me like valves A and C are to isolate the electric water fill valve for service. And valve C is not on the pressure relief pipe.

    I would say your automatic water fill system is malfunctioning and / or the manual fill valve B is leaking. The LWCO may be is calling for water when it should not be or the electric fill valve is leaking.

    DHW coil leaking into the boiler ?
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • seandempsey
    seandempsey Member Posts: 28
    Waher said:

    Does your pressure gauge always read close to 10psi? Your pressuretrol looks like it set for less cut-out pressure than that which may indicate the gauge is faulty, your pressretrol is faulty, or your pigtail is clogged. The boiler not operating properly could be the reason your water levels in the sight glass are off, or the sight glass may be not working properly, or the autofiller may be not working properly. You have many things going on simultaneously which aren't right which have to be eliminated to narrow down where the problem lies.

    The tech should never have left your property without forcing you to replace the sight glass valves. That's not a safe operating condition.

    The pressure gauge has never changed its reading, the times I've had it looked at, none of the techs seemed concerned, and I didn't know if I should request a repair or not. I've asked if it's something that needs to be replaced and monitored and didn't get a clear indication either way.

    The pressuretrol pigtail was removed and cleaned out and put back this last time, so I don't believe it's clogged.

    I just did another blowdown where I shut of the valve to the autofeeder and I was able to get the water level down below the sharpie line, and then I opened the valve below the feeder and added enough water to get it back up. As of the time of this writing, the water level is back to the desired level in the sight glass - though I will check it again later and tomorrow and see if this is changed.

    The sight glass does go down though, after about the 4th bucketfull it would drop quite readily.

    I can request the sight glass valves be replaced. I had the glass tube replaced when I moved in at the end of 2020, it was cracked and dripping, but the fittings were not replaced.


    Now to Jamie:

    First of all. Ir looks like valve C is on the pipe to the pressure relief valve. This is extremely dangerous, as if that valve gets closed for some reason you no longer have a pressure relief. Turn off the boiler and leave it off until you can get that valve removed.

    Now,whatever else is going on -- and I think there are a number of things -- the fact that the sight glass does not seem to accurately show the water level in the boiler is flat out dangerous. Before you panic, check it is possible to drain water from the boiler and if the level in the sight glass reflects that draining. You will need to close whatever valve or valves that can feed water to the boiler to do this. Then open whatever valve you use to manually feed and try adding water. The sight glass should respond.

    If the sight glass doesn't respond to that treatment, again you have a completely unsafe condition. Turn off the boiler and leave it off until you can get it fixed.

    Now you can set about figuring out what other problems you have and fixing them.

    The pressure release does NOT have that valve, that was a very unfortunate photo angle; I went down and took another picture to make sure and it was just a parallax, the valve C is seen in the photo is coming off the feeder and not connected to the pressure valve and pipe.

    In the other photo you can see I got the water level down to the level I believe it should be by shutting off the A valve to the feeder, blowing down another bucketfull, then I opened Valve B and heard the water flow and slowly raise the level to where you can see it now, then closed B and opened A.

    So to your note about the sight glass responding, it does seem to respond as expected once enough water was released, and then it watched it fill back up when opened the "direct" valve that bypasses the feeder (as the tech showed me).

    It's back to where it "should" be, but I don't think the DHW has fired, and the radiators haven't fired, so maybe I can check before/during/after the next heating window (tonight from 7 to 9) and see if it fills up the sight glass again.

    How does this update change things? Getting the sight glass valve handles fixed will be something I get done ASAP, regardless.






  • Jamie Hall
    Jamie Hall Member Posts: 23,164
    much better. Now that you know that the sight glass is responding, you can go ahead and figure out if water is leaking by another valve somewhere or whether the autofeeder is working...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    Chances are the auto feeder is leaking by, or it could be the tankless coil or the manual fill valve but the auto feeder (McDonnell Miller #47) is the most likely culprit.

    It should be taken apart and cleaned. The usual part that fails is the valve and strainer assembly. Do you really need an auto feeder? The parts for those thing are $$
  • JUGHNE
    JUGHNE Member Posts: 11,042
    I wonder if the installer used those stop & waste valves to give the ability to do a "broken union" test.

    If A is piped in with the arrow pointing to auto fill valve. Then close all 3 valves.... A B C.

    Then opening the drain port on C should pass little water. C arrow should point towards the auto fill valve.

    If C drain port only dribbles and stops, then with the boiler filled properly, open valve A.

    No water should pass, if so then the auto fill water valve is leaking.

    What direction is the arrow on B pointing?

    Or possibly installer was using up old stock....this happens.
  • seandempsey
    seandempsey Member Posts: 28

    Chances are the auto feeder is leaking by, or it could be the tankless coil or the manual fill valve but the auto feeder (McDonnell Miller #47) is the most likely culprit.

    It should be taken apart and cleaned. The usual part that fails is the valve and strainer assembly. Do you really need an auto feeder? The parts for those thing are $$


    Unless there's a reason the feeder is required for my setup, I don't have any reason to think I need it if I can monitor it myself, if that's more common. Like everything else with this old battle-axe of a home, it's been this way for 50-60 years, the home was maintained as a pastor dorm and snowbird's summer home.

    I would need to have a way to explain my request to whoever I can find to work on it, but if removing the feeder from the equation makes things more stable and predictable, that could be a good option. Or maybe it can simply have its electrical source disconnected and the valves closed.

    My new question would be: If the autofeeder was bypassed, what would be the implications, just checking the water level each day, each week? And if it's going down, investigate where the water is going?

    much better. Now that you know that the sight glass is responding, you can go ahead and figure out if water is leaking by another valve somewhere or whether the autofeeder is working...

    The auto feeder does work, when I do the blowdown normally I can hear it click and then sorta do this groan as it fills up and I can hear the water meter tick on my mains. The thing I don't know if it's adding water when it's not supposed to, or if it's adding too much, or even how it knows when to STOP, which is probably something I should learn. How *does* it know when to stop?

    JUGHNE said:

    I wonder if the installer used those stop & waste valves to give the ability to do a "broken union" test.

    If A is piped in with the arrow pointing to auto fill valve. Then close all 3 valves.... A B C.

    Then opening the drain port on C should pass little water. C arrow should point towards the auto fill valve.

    If C drain port only dribbles and stops, then with the boiler filled properly, open valve A.

    No water should pass, if so then the auto fill water valve is leaking.

    What direction is the arrow on B pointing?

    Or possibly installer was using up old stock....this happens.

    I will go document this and take pictures, I am not sure. I am slowly learning with each new forum post or technician call :) But, I am starting to understand how it all works. I am considering even making a schematic of all this for the questions I will invariably have in the future too.


    I've been going and eying the water level a few times a day, especially during and after the heating cycle. It did go down a tad in the sight glass while heating, which I presume is because it turned into steam, and then it was back up by the time the condensate returned.

  • JUGHNE
    JUGHNE Member Posts: 11,042
    You can simply shut of valve A, which feeds the water filler.
    Then open it to fill boiler as needed.

    You still need to blow down the Low Water Cut Off, That is the primary safety to shut down the fire in the event the boiler water drops below a safe level, without enough water in the boiler you can dry fire and crack the CI block or worse if boiler becomes red hot than hitting it with water can cause an explosion....as seen on TV.

    The burner should be running when you blow down and shut down and relight after level is safe.

    Many people do not have an auto fill but rely upon the LWCO to insure safety.

    Google "the broken union test" for a better explanation of what I was trying to say.
  • Jamie Hall
    Jamie Hall Member Posts: 23,164
    The autofeeder should shut off when -- depending on the kind of feeder -- either it has fed a set amount of water or the control float has risen a certain amount. There is a difference in water level between when the feeder is activated (a lower level) and when it shuts off. At a still slightly lower level, the same float system should shut off the boiler -- as noted above. If it's a float control. Some systems use an electronic probe, but the control interval principle is the same, even if the mechanism is quite different.

    Autofeeders are one of those gadgets which some people like -- and some don't. If you can be reasonably certain that the low water cutoff does work, and that someone will check the boiler water level frequently and add water as needed, then you don't really need one. It's that "frequently" that's the joker in the deck. For a residential system, my own opinion is that "frequently" means daily, particularly in colder weather -- but I'm a pretty conservative sort. It really depends on how long you can tolerate the heat being off if the water level, for some reason, gets low. The argument in the other direction, of course, is that they have been known to occasionally fail open and flood the boiler -- I've had that happen.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • exqheat
    exqheat Member Posts: 178
    The fill mechanism has a filter which may need cleaning. Rust may be keeping the fill mechanism from closing completely. Like a carburetor the fill mechanism is a needle in a small hole. Any debris would interfere with closing.
    John Cockerill Exquisite Heat www.exqheat.com Precisions boiler control from indoor reset.
  • seandempsey
    seandempsey Member Posts: 28
    Back for a quick update and additional information:

    In the 2 weeks since originally posting and troubleshooting, the water level was stable at the 60% height on the sight glass and I would check it twice a day. There have been plenty of days where the heating ran more than average, so lots of time to see how the heating cycle impacts it.

    In that time, I did a blow down and drained the brown water by shutting off the feeder's valve, draining it down til the water was clear, then using the other manual valve to restore the water level. Worked just as I understand it is supposed to. Went another several days, water level stable.

    However, today the sight glass was full. Let me describe what I observe.
    - See full sight glass.
    - Close feeder valve, open blow down into bucket.
    - Water level doesn't go down for the first few seconds, but once the bucket is about 50% full the level starts to drop fairly quick. I get it down to about 75% on the glass before the bucket is full, about 2 gallons.
    - The water level bobs up about half an inch, then down 1/4 inch, then back up, then back down, for a few seconds until the sight glass if full again (my question about "where does this water come from" is below).
    - I empty the bucket and fill it again, watching the sight glass now drop as I fill the bucket again. The water is clear now, and the sight glass shows the level at the 60% mark, which is where it is supposed to be according to the boiler.
    - I dump the water out, open the feeder valve, water is stable.


    Question 1: As I watched the water slowly fill back up after the first bucket, I don't understand where the new water is coming from to fill it up as I am draining it. I can normally hear the water running if its coming through the meter as it's just a few feet away, so I don't think it's coming from fresh water. My only uneducated thought is that this is condensate?? If water isn't coming into the boiler from the water main, where else is this coming from? I could be wrong and maybe the water is coming from the mains, but typically it's very obvious when it's flowing through the meter.

    Question 2: The sight glass fills back up while filling the first bucket full, sort of bobbing up and down slowly as it returns to 100%. But on the second bucket full, it remains at 60% as intended. What is going on between the first and second bucket full where the first isn't enough drained, but the second is, and why doesn't the 2nd bucketfull cause the level to slowly bounce like the first?


    This may be normal behavior and just a part of the ongoing monitoring and maintenance, I would like to keep monitoring and investigating though. So I guess I have a third question:

    Question 3: Is this just normal behavior and part of the art-science of good boiler operation?

    exqheat said:

    The fill mechanism has a filter which may need cleaning. Rust may be keeping the fill mechanism from closing completely. Like a carburetor the fill mechanism is a needle in a small hole. Any debris would interfere with closing.

    I can ask the technician I have access to about this, and if not, explore if this is something I trust myself to do. I worry about this old stuff, opening something up and realizing it can't be put back together, and Bangor's steam technician population seems smaller and smaller each year :)
  • Jamie Hall
    Jamie Hall Member Posts: 23,164
    I guess the real question is why did the boiler overfull.

    To the question of letting some out, then watching it slowly come back and then stabilising after a second drain -- you got water somehow well up into the returns. That's going to take time to come back, even if they are clean, and if they are a little gunky, which they probably are, it's going to take longer. So that's questions 1 and 2.

    Now back to the real question, and my bet is that the autofeeder called for water -- and got it -- but didn't shut off properly.. If the control for that is a float type, it's quite possible that the float stuck down. Otherwise, it is possible that the fill valve on the autofeeder is sticky. Not leaking by -- you'd see that in a gradual rise in water level over time -- but gets stuck open.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    If you disable /disconnect feeder you will need something else for a low water cutoff
  • JUGHNE
    JUGHNE Member Posts: 11,042
    I haven't read all the postings. A usual suspect for this is the HW coil in the boiler.

    Have you shut off the cold supply to the tankless coil in the boiler?

    Only the cold supply, leave the hot on.

    It would mean going some hours without HW.

    There could be a hole in the coil overfilling the boiler.
  • seandempsey
    seandempsey Member Posts: 28

    I guess the real question is why did the boiler overfull.

    To the question of letting some out, then watching it slowly come back and then stabilising after a second drain -- you got water somehow well up into the returns. That's going to take time to come back, even if they are clean, and if they are a little gunky, which they probably are, it's going to take longer. So that's questions 1 and 2.

    Now back to the real question, and my bet is that the autofeeder called for water -- and got it -- but didn't shut off properly.. If the control for that is a float type, it's quite possible that the float stuck down. Otherwise, it is possible that the fill valve on the autofeeder is sticky. Not leaking by -- you'd see that in a gradual rise in water level over time -- but gets stuck open.

    Ah, that makes sense.

    I will do some good photos of the feeder setup and all the labels / numbers / etc I can find on it. I am not sure if it's a float type or not. I can hear the feeder "click" which sounds to my ear like when a relay clicks, but that also could be a float triggering a relay.

    Either way - I need to do some photography and documentation!!
  • gunn308
    gunn308 Member Posts: 11
    I'm in the great city of Bangor and try to maintain 2 buildings in downtown one is 2 pipe steam with 2 HB Smith series19 -7 section boilers. The best around for steam is Steve@ Huntley Oil
  • seandempsey
    seandempsey Member Posts: 28
    gunn308 said:

    I'm in the great city of Bangor and try to maintain 2 buildings in downtown one is 2 pipe steam with 2 HB Smith series19 -7 section boilers. The best around for steam is Steve@ Huntley Oil

    Thank you, I will add them to my list of contacts!



    I've returned with the photos of the feeder. I appears to be connected to a LOT of fittings and pipes. There is that square nut that may be a cleanout our inspection hole perhaps? I have a cheap snake endoscope camera I can put in there and look around. I presume the acorn thing normally maintains a water level that matches the sight glass, yes? I am realizing now that the top of the acorn is almost aligned with the proper water level indicator, so maybe it's always full to the top?

    I am going to put a cheap wifi camera on the sight glass and see if I can catch when the water rises. I set the water level twice yesterday, and then it's stable again today. If the feeder is acting up and overfilling, that seems like the most likely event.

    This never occurred for the first 24 months in living here, so whatever is adding water, it seems to be something that is a new behavior, and the age of the whole acorn autofiller is definitely suspect here.








  • seandempsey
    seandempsey Member Posts: 28
    I emailed McDonnell & Miller to see about IDing this, and their response was:

    "With all due respect, this needs to be replaced.

    The units are 55-60 years old."

    🤣 I agree... I am guessing that a replacement is a whole ball of wax requiring someone with advanced knowledge, so maybe just finding a 1:1 replacement to redo the whole assembly is now the next step??
    ethicalpaul
  • 109A_5
    109A_5 Member Posts: 1,377
    Hello @seandempsey,

    I emailed McDonnell & Miller to see about IDing this, and their response was:

    "With all due respect, this needs to be replaced.

    The units are 55-60 years old."

    🤣 I agree... I am guessing that a replacement is a whole ball of wax requiring someone with advanced knowledge, so maybe just finding a 1:1 replacement to redo the whole assembly is now the next step??

    Typically M&M recommends 10 year replacement with this type of equipment (very expensive in my opinion). However in the right hands these old systems can be cleaned and repaired. A new Low Water Cut Off and water feeders are not without their problems too.

    To me you still don't know the water source. I would close the two valves on either side of the auto feeder and maintain the Boiler's water level with the manual fill during the test. The auto feed system is probably the most likely cause but why not be more sure ?




    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • KC_Jones
    KC_Jones Member Posts: 5,722
    To answer one of your questions, based on what I see in those pictures and your description. The feeder is connected through the sight glass, so when you flush or drain, you are draining the sight glass first, then the boiler. So it's not that new water is coming in, the sight glass is just filling back up with boiler water from you draining it. Some of us have sight glass drain valves for flushing the sight glass and when you open that up the sight glass will go completely dry the whole time. I'm pretty sure that's what you are seeing here.

    I also agree with McDonnell on this one, that whole thing should be replaced.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    ethicalpaul
  • exqheat
    exqheat Member Posts: 178
    edited March 2023
    I have had success replacing the lower filter unit. Get the drawings on the web.
    John Cockerill Exquisite Heat www.exqheat.com Precisions boiler control from indoor reset.
  • exqheat
    exqheat Member Posts: 178
    McDonnell & Miller CTRD-101 CART STRNR 310453 MM_310453 Xylem
    John Cockerill Exquisite Heat www.exqheat.com Precisions boiler control from indoor reset.
  • seandempsey
    seandempsey Member Posts: 28
    109A_5 said:


    To me you still don't know the water source. I would close the two valves on either side of the auto feeder and maintain the Boiler's water level with the manual fill during the test. The auto feed system is probably the most likely cause but why not be more sure ?

    Good idea, I can do this.



    KC_Jones said:

    To answer one of your questions, based on what I see in those pictures and your description. The feeder is connected through the sight glass, so when you flush or drain, you are draining the sight glass first, then the boiler. So it's not that new water is coming in, the sight glass is just filling back up with boiler water from you draining it. Some of us have sight glass drain valves for flushing the sight glass and when you open that up the sight glass will go completely dry the whole time. I'm pretty sure that's what you are seeing here.

    I also agree with McDonnell on this one, that whole thing should be replaced.

    Ah, yes, I understand what you're saying. That makes sense. I should probably make a map of the flow of everything, get some paint pens and write on the pipes some arrows of how it all works.


    I think I will try closing off the feeder and testing it and watching the levels for a few days. What is my risk profile with that? I don't think I am "losing" water anywhere that the low-water cutoff would kick in, but I also don't know what is triggering the potential feeder to fill it up if it never goes down. I don't have any water leaks I can see, so if the water is escaping as vapor/steam and slowly lowering over the course of a week or 2 until the feeder kicks in, maybe that's what is going on. My radiator valves do hiss a little bit at first, so they probably lose a little water as vapor.

  • exqheat
    exqheat Member Posts: 178
    McDonnell & Miller CTRD-101 CART STRNR 310453 MM_310453 Xylem
    John Cockerill Exquisite Heat www.exqheat.com Precisions boiler control from indoor reset.
  • seandempsey
    seandempsey Member Posts: 28
    JUGHNE said:

    I haven't read all the postings. A usual suspect for this is the HW coil in the boiler.

    Have you shut off the cold supply to the tankless coil in the boiler?

    Only the cold supply, leave the hot on.

    It would mean going some hours without HW.

    There could be a hole in the coil overfilling the boiler.

    I missed this post the first time; I don't have information on this yet, but this is a good place to start!

    I have not messed with the tankless coil at all, mostly because I didn't think of it, and then also just because of the usage of hot water in the house. But, perhaps I could try shutting off its valve for a day and not use any hot water, see what happens.

    I'll take a closer look. The coil has a stamp on it of the year it was installed, I know it was in the 2000's at least, maybe 2005... but I will look. Thank you for bringing this up!

    I have had the idea to switch to a heat pump water heater and stop using the coil, but I was also told that would require converting the whole unit to a cold-start, which I don't know enough about YET, but I'll look into that more.




  • JUGHNE
    JUGHNE Member Posts: 11,042
    I can not believe this would not have been among the first things that are at suspect.

    Find the COLD supply line going TO the coil and leave it off as long as possible and see if the water line stays more steady.

    Also, when you blow down the LWCO you should do so when the burner is operating and make certain that the burner shuts down. That is the electric switch "click" you heard when flushing out water.

    That device has 2 functions: it is a water feeder and also the main and almost only safety device on a steam boiler.......very serious consequences if it does not shut the burner down when no water conditions occur.
  • exqheat
    exqheat Member Posts: 178
    edited March 2023
    "I can not believe this would not have been among the first things that are at suspect."

    Believe this. Not everyone knows everything. Questions are the gate to wisdom. Encourage curiosity. There are no stupid questions. If you know something share it.
    John Cockerill Exquisite Heat www.exqheat.com Precisions boiler control from indoor reset.
  • 109A_5
    109A_5 Member Posts: 1,377
    JUGHNE said:

    I can not believe this would not have been among the first things that are at suspect.

    It was mentioned back on Feb 11. Perhaps the OP missed it.
    With the intermittent nature

    In the 2 weeks since originally posting and troubleshooting, the water level was stable at the 60% height on the sight glass and I would check it twice a day. There have been plenty of days where the heating ran more than average, so lots of time to see how the heating cycle impacts it.

    In that time, I did a blow down and drained the brown water by shutting off the feeder's valve, draining it down til the water was clear, then using the other manual valve to restore the water level. Worked just as I understand it is supposed to. Went another several days, water level stable.

    However, today the sight glass was full. Let me describe what I observe.
    - See full sight glass.

    I would think a DHW coil would leak more than that ? Maybe the leak seals itself back up with corrosion.
    Anyway explore (test) each scenario one at a time.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • seandempsey
    seandempsey Member Posts: 28
    JUGHNE said:

    I can not believe this would not have been among the first things that are at suspect.

    Find the COLD supply line going TO the coil and leave it off as long as possible and see if the water line stays more steady.

    Also, when you blow down the LWCO you should do so when the burner is operating and make certain that the burner shuts down. That is the electric switch "click" you heard when flushing out water.

    That device has 2 functions: it is a water feeder and also the main and almost only safety device on a steam boiler.......very serious consequences if it does not shut the burner down when no water conditions occur.

    This makes sense, and I do appreciate the different input from the forum members.

    I do know that I have witnesses the LWCO turn off the boiler during the blow down, both when I've done it and when servicemen have. I can give it a sanity check again today, but that much I did know to observe for proper function. I'll ensure the LWCO does work though, because there's no real telling if it has an issue since the last time it was observed to turn off the burner.
    109A_5 said:


    I would think a DHW coil would leak more than that ? Maybe the leak seals itself back up with corrosion.
    Anyway explore (test) each scenario one at a time.


    I put a zip tie around the sight glass where the water line is and I will be able to see if there's an incremental raise. So far, I haven't seen a steady increase that would point to the DHW coil, it will be stable in the sight glass, then one day it's just completely full, so the zip tie will let me monitor small increases and I can shut off the cold intake to the coil for a day and tell people not to use hot water for half a day.




  • seandempsey
    seandempsey Member Posts: 28
    UPDATE: So the "boiler cam" has been in place, I can record 3 days worth of continuous video, so each day I have been checking it, watching how the level changes, etc.

    It hasn't overfilled at all yet, but as fate would have it, today I discovered it was LOW about half an inch in the sight glass after being stable, and I go down and discover a whole new issue: the sigh glass is dripping.

    I have been checking the sight glass 2-3 times a day manually, and then with the camera, so this sudden drop seems to have started either yesterday or today. I can't believe this sort of coincidence.

    But anyways, I called my boiler guy who seems to be the most willing to come work on my old beast, I reckon we'll need to rebuild the sight glass assembly and probably just replace the valves while we're at it.

    I know that there are no coincidences, so this one will haunt me a bit. I check the floor beneath the boiler each time I am there and today instantly noticed the wet water, so either this is just unrelated, or a cascade of something. Or, maybe it really is just unrelated.

    I put a bucket under it to monitor the amount and got a call in to the service guy. 🤦‍♂️ always something.





  • 109A_5
    109A_5 Member Posts: 1,377
    Hello @seandempsey,
    Looks like it may have been leaking before and now you caught it in the act.




    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • seandempsey
    seandempsey Member Posts: 28
    109A_5 said:

    Hello @seandempsey,
    Looks like it may have been leaking before and now you caught it in the act.




    Yeah, probably about 2 years ago now, the glass was leaking and I had a different service company replace the glass, but not the couplings, so maybe this is something more to do with the fittings causing a recurring issue. But, that time I didn't know to ask about replacing the couplers and valves to have proper handles, no idea why whoever's hands they broke off into didn't replace them... the woes of living in a snowbird's old house.
  • 109A_5
    109A_5 Member Posts: 1,377
    Hello @seandempsey,
    To me it looks like there is corrosion (or sediment) building up on the outside of the 2 year old glass (just above the compression nut). So I'm thinking this is not the first leak with that glass. Since the pictures are weeks old by now.
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • seandempsey
    seandempsey Member Posts: 28
    I can see why there are no handles on the valves; they don't fit against the y-split. So seems like I'd need some that are mirrored and oriented in the other direction (left handed vs. right handed) since they can't be flipped. The lower knob stem is all mangled now from all the people turning it with pliers, so that probably needs urgently replaced.

    Now, on the compression nut I did try to give it a gentle, slight tightening (righty-tighty) and that made the drip go faster, so I put it back where it was and the dripping didn't slow back down, so I tried to find a spot that would reduce it to where it was before I turned the nut, but no luck, so i made the dripping slightly faster now.

    I did turn the lower valve on the sight glass and close it, and the glass drained as it dripped until it was empty, but that lower valve's stem is very mangled and I fear it only has a few more open/close cycles of a pair of pliers grabbing it before it won't be able to be turned, so I opened it back up so I could see the water level and let it drip into the bucket and we'll see about getting parts or service on it.

    If closing that valve would let me remove the compression nut and examine the state of the seals and what is in the leaking area, I may be able to attempt that myself, but I'd much rather have someone with experience show me what is wrong and fix it, so we'll see if I can get a call in.

    Probably now a topic for a different thread about what replacing the sight glass's valves and couplings entails, and how to find ones that are mirror images of what is on there.







  • 109A_5
    109A_5 Member Posts: 1,377
    Hello @seandempsey,
    To me that is one of those things that 'You Don't TOUCH' unless you are prepared to repair it right then. If it was a lot older and and things were more seized up you may have cracked the glass. And no guarantee with the condition of the old valves either.

    If you want 100% functionality with replacement of the valves. Most modern water gauge valves stems come straight out (easy clean out back to the boiler) and are not 90 degrees to the taping going to the boiler. Also you could add a Tee to offset the gauge to the left and still have clean out assess to the path back to the boiler with the Tee installed.

    I put thick (almost unbreakable) gauge glass on my boiler with Teflon seals. I'll see if it works out better.
    I did not bother to replace the valves since I never close them.

    I try to do repairs like that in the off season, since there is no urgency then.
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
    BobC
  • seandempsey
    seandempsey Member Posts: 28
    109A_5 said:

    Hello @seandempsey,
    To me that is one of those things that 'You Don't TOUCH' unless you are prepared to repair it right then. If it was a lot older and and things were more seized up you may have cracked the glass. And no guarantee with the condition of the old valves either.

    If you want 100% functionality with replacement of the valves. Most modern water gauge valves stems come straight out (easy clean out back to the boiler) and are not 90 degrees to the taping going to the boiler. Also you could add a Tee to offset the gauge to the left and still have clean out assess to the path back to the boiler with the Tee installed.

    I put thick (almost unbreakable) gauge glass on my boiler with Teflon seals. I'll see if it works out better.
    I did not bother to replace the valves since I never close them.

    I try to do repairs like that in the off season, since there is no urgency then.

    Yah, I feel you. Learned that lesson.

    For now, I shut off the lower valve to stop the leak. I also noticed that the valve couplers are mirror images of each other and if you switched the top and bottom positions, the valve handles would have fit and not had to be removed. I can't imagine what the person was thinking during the install when they noticed the handles won't fit, but didn't just swap which one is on the top of the glass and which is on the bottom.

    I can probably get to Tuesday when the technician can look at it with me, lower the water level enough to possibly reverse the couplers and flip the class and clean it / replace it, or even just replace the entire assembly.

    I hesitate to think about trying to do it myself, mostly worrying about removing the valves from the boiler and then not being able to put it back together because something corroded and broke off or snapped from torque after being seized for many years.

    Trying to avoid zero heating and zero hot water, those cold showers with Maine city water in March are about 33F. Maybe it's time to also more seriously think about an alternative hot water source than the boiler, doing something that disables our hot water for days would lead to a very angry wife.
  • 109A_5
    109A_5 Member Posts: 1,377
    Hello @seandempsey,

    I can't imagine what the person was thinking during the install when they noticed the handles won't fit, but didn't just swap which one is on the top of the glass and which is on the bottom.

    Often there is a drain on the lower valve assembly. It is often ignored, but probably should not be.

    From what I can see, I would have just added a Tee or a Cross and a nipple to each valve assembly to offset the Water Gauge assembly to the Left and not cut off or removed the handles.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System