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Can't get Weil Mclain eg-40 restarted

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JoeDi
JoeDi Member Posts: 43
edited October 2020 in Strictly Steam
Hi, my first few years with this boiler i left the pilot going in the summer and just never turned it off. Then last year I did a lot of work to the boiler and felt I understood it well enough I could easily shut off the gas in the spring and then restart it in the fall.

However, I just tried to get it started and i ensured gas on, boiler switch is on and I turn the gas control valve to Pilot and depress and it seems no gas is moving. I dont hear gas, I dont smell gas even after holding the button trying to light with a bbq lighter many times.

I'm not sure what I could be doing wrong or what else I should try.... One thing I will mention I noticed the gas valve when I depress t he knob on pilot, if its not in the perfect position it doesnt go in as far, but i did wiggle it until it depressed all the way and it still wouldnt start.

Do I have a bad gas control valve or i noticed some crud on the pilot, could the pilot get clogged after sitting perhaps (would the gas not blow any dust out when its turned on?)

Also, is this a bad idea to normally shut these down (especially old ones that have never shutdown?)

Thanks much guys.

EDIT: i forgot to mention I did shut it down last yeaar to clean the burners and had no issue restarting it then. so i am 99% sure i am doing the procedure correctly. Also the low water cut off red light is OFF so its not that. (it lights up when its too low and off when its good i am 99% sure)


I was thinking of trying to adjust the pilot up a bit to see if that helps..... Should I smell gas if i hold the pilot down for a bit?


Here is a pic of the gas valve:



If I need a new one, does anyone know how I figure out a suitable replacement? can I order a similar one on amazon from like Honeywell? Or do I need to go to a heating place and bring that old one with me to get the exact same one? THanks

Comments

  • mattmia2
    mattmia2 Member Posts: 9,653
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    It may be difficult to get close enough to the pilot burner to smell gas before it dissipates. Is the valve before the boiler off? It is possible for pilot burners to clog but just sitting over the summer seems unlikely. you could unscrew the pilot burner fitting at the valve and see if there is gas there when you press the knob/button. even better yet hook a manometer up to it and press the button and see if you have pressure.
    JoeDi
  • JoeDi
    JoeDi Member Posts: 43
    edited October 2020
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    Yeah I confirmed the valve before the burner is ON. I also tried to turn the pilot adjustment screw out 2 turns to increase it and didnt matter. Shouldnt I hear some gas hissing at least?

    I dont have a manometer but i can get one cheap from amazon quickly it seems would this work? https://www.amazon.com/Manometer-Pressure-Differential-Diameter-Hti-Xintai/dp/B07R3J4ZJ4/ref=zg_bs_5006565011_1?_encoding=UTF8&psc=1&refRID=VE46MH1R80B6J7QYC9K1

    the info of the valve is on the side i cant see i used my phone to snap this:



    i think its discontinued, old essex one ,i found a used one on ebay that was it.
  • JoeDi
    JoeDi Member Posts: 43
    edited October 2020
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    Is there a way i can check for 24v on the gas valve to rule out an electrical thing? there are 3 terminals, TH, TR and THTR. how should i check for 24v? I am going to try to hunt for a manual on it too.

    EDIT: i just took the pilot out and put my nose to it and smell nothing when i depress the pilot.
  • JoeDi
    JoeDi Member Posts: 43
    edited October 2020
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    my pilot must be clogged. i removed the pilot tube from the pilot assembly and smell g as instantly coming from the ferule. tried cleaning the top of the pilot where the white crud is (the pilot was WAY too high, i adjusted it last year) with a wire brush but no joy. gas smell goes away once i screw the line back in.

    can i poke something through the other end of the pilot? the pilot shield/flame diverter hood is in the way so i cant really clean it good from the top. thanks
  • mattmia2
    mattmia2 Member Posts: 9,653
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    Might have to take the main burner out or whatever the pilot burner is mounted to to get to it.
    JoeDi
  • JoeDi
    JoeDi Member Posts: 43
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    mattmia2 said:

    Might have to take the main burner out or whatever the pilot burner is mounted to to get to it.

    I did, i have it out just not sure what to do next. Cleaning the top of the pilot didnt help.

    Here is what it looks like:








  • mattmia2
    mattmia2 Member Posts: 9,653
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    You can try cleaning with something plastic. you should be able to blow through it when it is clear although at a very low volume.
    JoeDi
  • luketheplumber
    luketheplumber Member Posts: 149
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    could it have rusted shut due to humidity over the summer? maybe soaking it in white vinegar would help.
    I just earned my GED and am looking for a apprenticeship with one of these steam gurus on this site!
    JoeDi
  • JoeDi
    JoeDi Member Posts: 43
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    could it have rusted shut due to humidity over the summer? maybe soaking it in white vinegar would help.

    very possible, had a very very humid summer. i will try soaking it.
  • JoeDi
    JoeDi Member Posts: 43
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    mattmia2 said:

    You can try cleaning with something plastic. you should be able to blow through it when it is clear although at a very low volume.

    I dont think plastic will work, its pretty badly clogged. Could I use a thin piece of wire? I was thinking maybe finding a thin gauge wire and trying to poke a hole through the crud
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
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    There are special nozzle cleaning wires in a sort of Swiss Army Knife arrangement of different sizes, for that purpose, and also replacement pilot light assemblies.—NBC 
    JoeDimattmia2
  • JoeDi
    JoeDi Member Posts: 43
    edited October 2020
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    There are special nozzle cleaning wires in a sort of Swiss Army Knife arrangement of different sizes, for that purpose, and also replacement pilot light assemblies.—NBC 

    EDIT: I went to the local heating supply place and found a replacement pilot assembly that looks like it will work. I also bought a new thermocouple because the existing one clips in to the old assembly and the new assembly has a large hole so I needed the holder that comes with a new thermocouple.

    New and Old Assembly:





    I had to use PB Blaster to remove the old pilot assembly, is that a problem to have PB Blaster on the burner? I have already brushed the main burner with a soft wire brush but its still loaded with crud from t he pilot being too high previously. Is there something I can use to safely clean the burner? This is what it looks like:






    Any idea what type assembly I would need based on my pictures? I bought a replacement one last year from the heating supply but its not the correct shape/orientation and i dont think i can adapt it to make it work. Looking online it seems there are various mounting bracket styles (A, B, C, etc). I think I need a B but i am not 100% sure.
  • mattmia2
    mattmia2 Member Posts: 9,653
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    You should probably have someone that has combustion analysis equipment and knows how to use it clean and adjust the boiler at some point soon, it doesn't look like that has been done in a long time.

    The issue with using wire to clean the burner is that it can change the size of the orifice.
  • JoeDi
    JoeDi Member Posts: 43
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    mattmia2 said:

    You should probably have someone that has combustion analysis equipment and knows how to use it clean and adjust the boiler at some point soon, it doesn't look like that has been done in a long time.

    The issue with using wire to clean the burner is that it can change the size of the orifice.

    Thanks, I am going to try and get someone in at some point to do a combustion test.

    The wire brush I used to clean the burner was really soft wire brush, it didnt do any damage but i was able to get a decent amount of the gunk off.

    I was able to get the pilot replaced and now the boiler is working again.

    My only concern is that the pilot seems a bit high to me, is this normal?

    https://youtu.be/87spCQZlTsw

    I tried to adjust it down but the adjustment screw on the gas valve isnt really making much of a difference.
  • mikeapolis
    mikeapolis Member Posts: 46
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    I'm curious about the condition of that heat exchanger.
    Any chance you could put your phone underneath and snap a couple pictures?
    JoeDi
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,838
    edited October 2020
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    The pilot flame in the video is perfect. Do the main burners light properly? Smooth without a big puff and flame roll-out?

    You probably don't need it but, you can get the main burner with a pilot bracket from a Weil McLain distributer. Part number/description:
    512-200-001 Burner, Stainless Tube With Pilot Bracket: PI System (All Sizes)
    Burner w/o bracket is part number 512-200-000

    https://www.supplyhouse.com/Weil-McLain-512-200-001-Burner-Steel-Tube-w-Pilot-Bracket-for-EG-EGH-Boilers
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    JoeDi
  • JoeDi
    JoeDi Member Posts: 43
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    I'm curious about the condition of that heat exchanger.
    Any chance you could put your phone underneath and snap a couple pictures?

    Unfortunately for me your hunch seems on point.....







    I'm guessing that is a leak? I've never noticed anything dripping or anything like that. Even all summer there was neever any water under the boiler. I know this cant be fixed, its going to require a new boiler right? I really hope it can make it until next year though, this isnt the ideal year to have to buy a new one for me.

  • mattmia2
    mattmia2 Member Posts: 9,653
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    Is ti steam or hot water? Does that actually feel wet or is it just something wet looking? If it is a leak it could be some fitting in to the boiler. If ti is between sections it is sometimes possible to disassemble it and replace the leaking gasket if it is a gasketed boiler.
  • JoeDi
    JoeDi Member Posts: 43
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    mattmia2 said:

    Is ti steam or hot water? Does that actually feel wet or is it just something wet looking? If it is a leak it could be some fitting in to the boiler. If ti is between sections it is sometimes possible to disassemble it and replace the leaking gasket if it is a gasketed boiler.

    It's a steam boiler. a Weil Mclain EG-40. Its I'm not entire sure its the original energy sticker on it because its peeling off and looks like it could have been removed from the previois boiler, but if it is it says this boiler was from 1991. So like 30 years old.

    I dont feel anything wet at all. I dont think its a fitting because from what I can tell there are no fittings in that area but i am not 100% sure.

  • JoeDi
    JoeDi Member Posts: 43
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    The pilot flame in the video is perfect. Do the main burners light properly? Smooth without a big puff and flame roll-out?

    You probably don't need it but, you can get the main burner with a pilot bracket from a Weil McLain distributer. Part number/description:
    512-200-001 Burner, Stainless Tube With Pilot Bracket: PI System (All Sizes)
    Burner w/o bracket is part number 512-200-000

    https://www.supplyhouse.com/Weil-McLain-512-200-001-Burner-Steel-Tube-w-Pilot-Bracket-for-EG-EGH-Boilers

    Thanks! I was wondering if I could get a replacement or not. Not too expensive either. If it gets any worse I will order one.

    The burners seem to light perfectly, no big puff and no flame roll out that i can tell.

  • Jamie Hall
    Jamie Hall Member Posts: 23,303
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    From the look of it I would hazard a guess that what you have there is a leak between sections. Weil-McClain uses an O-ring between sections (well, not really an O-ring; it's got a square cross section), and they can, over time, leak. You might be able to get someone to take the sections apart -- but it the leak has been going on for any length of time it's likely that the sealing surfaces are damaged.

    So...

    Keep an eye on your water usage. If it starts to really go up, it's time to change. Also, keep your pressure down -- that can help a lot.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    JoeDimikeapolis
  • JoeDi
    JoeDi Member Posts: 43
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    From the look of it I would hazard a guess that what you have there is a leak between sections. Weil-McClain uses an O-ring between sections (well, not really an O-ring; it's got a square cross section), and they can, over time, leak. You might be able to get someone to take the sections apart -- but it the leak has been going on for any length of time it's likely that the sealing surfaces are damaged.

    So...

    Keep an eye on your water usage. If it starts to really go up, it's time to change. Also, keep your pressure down -- that can help a lot.

    Thanks Jamie, I am going to monitor it. I have the pressure down pretty low so i shouldl be good as far as pressure. I dont even see movement on a 3psi gauge its operating so low.

    So far so good on water usage, last year was good too.

    Would it be helpful to keep the water level lower so the water doesnt rest above the section seal? Like keep it at maybe 1/2 instead of 2/3?

    Also, this is a bit off topic but 2 questions for everyone....

    1) does keeping the water level lower in the fall and spring help to boil the water faster and get steam upstairs faster so the basement doesnt get too hot? this time of year the basement gets so crazy hot because its already maintaining a warm 73F temp but then the boiler is running to warm the upstairs.

    2) how close to the boiler can I go with pipe insulation? Can I put pipe insulation on the near boiler piping? When I moved in there was ZERO insulation in the basement, the previous owner had the asbesstos removed from the exposed basement pipes (still iinsulated with asbestos in the walls).

    Since then I have insulated all the basement pipes EXCEPT the near boiler piping, but that stuff puts out a lot of heat, so if i could insulate it, that would be helpful.

    Thanks!

  • Jamie Hall
    Jamie Hall Member Posts: 23,303
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    On the water level -- won't make much difference, either to a potential leak -- or to how fast the boiler heats up. So keep it where it says to, more or less.

    If you are using fiberglass insulation, as you should be, you can go right down to the boiler on the risers, and all the near boiler piping as well. No problem.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • JoeDi
    JoeDi Member Posts: 43
    edited December 2020
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    I havent yet had someone come out to do a combustion analysis but I've been working on a smart co2 sensor and its been running in my basement for the past week and I noticed that normally the basement is 400-600ppm of CO2. Then randomly throughout the day it spikes to 1100-1200ppm of CO2. It took me a while but eventually I correlated it to when the steam boiler runs. I noticed on days it was sunny out and the boiler didnt run for a while there were no spikes and on cold nights it spiked a lot.

    From what I can tell the co2 level spikes when the boiler stops running, not while its running. For example the boiler ran last night from 7pm to 7:30pm and the co2 spiked at 7:35pm.

    At first i worried could it be CO tripping my co2 sensor but I have good carbon monoxide detectors in my house, i have one on each floor including the basement and there has been zero detected.

    I was thinking, what happens 5 minutes after the boiler runs is the steam condeses back to water and my vents open and release all the air in the system as the steam condenses. Does this air in the system contain a higher level of Co2 perhaps? EDIT: I am wrong, it starts spiking as soon as the boiler is running. So it definitely seems the running boiler itself raises the co2 levels in the room. (but not a lot 1200ppm is not that high)

    PS. My co2 sensor is supposed to be temperature compensated so i dont think its the temp going up in the basement when the boiler runs that causes the reading to go up....

    thanks.
  • Jamie Hall
    Jamie Hall Member Posts: 23,303
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    The vents don't "release air in the system". They allow air out of the system when the boiler starts to steam, and allow air back in when it shuts down.

    Free air carbon dioxide levels are currently around 400 ppm -- more in urban areas, slightly less in the country. I would be concerned that you are seeing some stack gas leakage from your boiler breaching -- and I would look to find out why. And fix it...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • JoeDi
    JoeDi Member Posts: 43
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    The vents don't "release air in the system". They allow air out of the system when the boiler starts to steam, and allow air back in when it shuts down.

    Free air carbon dioxide levels are currently around 400 ppm -- more in urban areas, slightly less in the country. I would be concerned that you are seeing some stack gas leakage from your boiler breaching -- and I would look to find out why. And fix it...

    The normal CO2 levels in my house sealed up for the winter is around 400-600ppm, i measured in areas away from the boiler. I am in a somewhat urban area so its a little higher outside than normal, usually around 500's in the middle of the day. So it looks like the boiler running causes an additional 400ppm-600ppm of CO2 to develop in the basement for a short time after the boiler runs.

    The breaching is the hole in my chimney where the boiler connects, correct? If I was leaking gas enough to raise the CO2 levels wouldnt there also be carbon monoxide as well though? I guess perhaps there is but not enough for the detectors to trigger?

    To be honest I am in a covid hotspot and I am not too keen on having someone come into my house right now if at all possible to avoid. that is the reason I havent gotten the combustion test done yet. Is there anything I can check myself without a combustion analyzer?

  • mattmia2
    mattmia2 Member Posts: 9,653
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    Do you have low level CO detectors that will give you an actual numeric reading down to a coupel PPM, or only a UL device that will only alarm if there is a high level for a sustained period?

    If the boiler is burning cleanly there will be very little CO in the products of combustion.

    Does the boiler have a vent damper?

    How often doe the CO2 monitor log a reading?

    It could take some time for the CO2 from the boiler to diffuse to the sensor or it may be pulled up the flue with the heat of the flue gases while it is running then as it cools it loses draft and products of combustion in the boiler or the chimney fall out in to the basement.
    JoeDi
  • JoeDi
    JoeDi Member Posts: 43
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    mattmia2 said:

    Do you have low level CO detectors that will give you an actual numeric reading down to a coupel PPM, or only a UL device that will only alarm if there is a high level for a sustained period?

    If the boiler is burning cleanly there will be very little CO in the products of combustion.

    Does the boiler have a vent damper?

    How often doe the CO2 monitor log a reading?

    It could take some time for the CO2 from the boiler to diffuse to the sensor or it may be pulled up the flue with the heat of the flue gases while it is running then as it cools it loses draft and products of combustion in the boiler or the chimney fall out in to the basement.

    I thought the device I was using did low level because it has a lcd that starts at 0ppm but I believe you are correct and it only starts detecting at a higher level. Its cheaper so I bet it requires a dangerous level to start registering.

    I also have a Nest protect near the boiler which doesnt give any warning, they are extremely sensitive when it comes to smoke, so I would assume they are sensetive when it comes to CO as well but I cant find any specs on the nest website about what level it starts alerting.

    I guess I could buy a more sensitive low level CO detector but it looks like I would need to spend around $100 for a decent one.

    As far as the vent damper, no, my boiler doesnt have one. All it has is a box attached to the back of the boiler that is open completely on the bottom, that then goes into a 2ft long section of vent pipe and into the chimney breach.

    My co2 sensor logs a reading every 60 seconds but I could adjust it to read more often if i needed. After further testing, the CO2 level starts to rise as soon as the boiler starts running. I thought it was rising after it stopped running but I was mistaken.

    I was talking to some other people who use this sensor to confirm it was temperature compensating (it is) and one of them was saying the rise in co2 i am seeing is likely normal. They said the water in the boiler releases its CO2 when its boiled and absorbs it when it cools. Does that make any sense perhaps?

    Thanks.

  • mattmia2
    mattmia2 Member Posts: 9,653
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    If you have the nighthawk co detectors I believe they will read down to a couple ppm and store peak vales if you press the button. read the manual.

    I'm pretty sure you have some sort of draft issue if the co2 starts rising as soon as it fires. there are calculations you need to do with the size of the chimney and connector and the length and rise of the connecto r as well as what happens to the chimney above the roof that have to be right for it to draft properly.

    The soluability of co2 in water does change with temp but not enough for what you are seeing.
  • Jamie Hall
    Jamie Hall Member Posts: 23,303
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    The Nest Protect part number S3000BWES does have a CO detector, but I can't seem to find a specification for alarm level.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • JoeDi
    JoeDi Member Posts: 43
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    mattmia2 said:

    If you have the nighthawk co detectors I believe they will read down to a couple ppm and store peak vales if you press the button. read the manual.

    I'm pretty sure you have some sort of draft issue if the co2 starts rising as soon as it fires. there are calculations you need to do with the size of the chimney and connector and the length and rise of the connecto r as well as what happens to the chimney above the roof that have to be right for it to draft properly.

    The soluability of co2 in water does change with temp but not enough for what you are seeing.

    It looks like the lowest the nighthawk can go is 30ppm. Would that be low enough for my purposes? If so I can pick one up they are only $28. The ones that go down to 1ppm are $115-$150, but its something i would likely only use once in a blue moon so if 30ppm is low enough I will just get a nighthawk.

    Regarding the draft, I used to have a massive cold air draft in my basement and last winter i sealed it up as best I could. I used spray foam and insulation board and sealed the rim joists and the windows, etc. It made my basement much warmer, could that perhaps be the issue with my draft? The house is still a 1930 built house so no matter how much i seal it up its still not going to be anywhere near as air tight as a modern house though.

    The Nest Protect part number S3000BWES does have a CO detector, but I can't seem to find a specification for alarm level.

    Yeah in the docs it says it will tell you the max PPM when it alerts you but it doesnt say how low it will alert unfortunately.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,838
    edited December 2020
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    JoeDi said:


    ...I was thinking, what happens 5 minutes after the boiler runs is the steam condeses back to water and my vents open and release all the air in the system as the steam condenses. Does this air in the system contain a higher level of Co2 perhaps?
    thanks.

    Does your EG boiler equipped with an automatic vent damper? If yes, how soon does it close after the burner shuts off?

    Also, Air flows in when the steam turns to condensate. The vents let air out when the boiler is steaming.
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • JoeDi
    JoeDi Member Posts: 43
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    JoeDi said:


    ...I was thinking, what happens 5 minutes after the boiler runs is the steam condeses back to water and my vents open and release all the air in the system as the steam condenses. Does this air in the system contain a higher level of Co2 perhaps?
    thanks.

    Does your EG boiler equipped with an automatic vent damper? If yes, how soon does it close after the burner shuts off?

    Also, Air flows in when the steam turns to condensate. The vents let air out when the boiler is steaming.
    Negative, doesnt have a damper.

    Regarding the air flow, sorry, Jamie already corrected me.
  • JoeDi
    JoeDi Member Posts: 43
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    JoeDi said:


    It looks like the lowest the nighthawk can go is 30ppm. Would that be low enough for my purposes? If so I can pick one up they are only $28. The ones that go down to 1ppm are $115-$150, but its something i would likely only use once in a blue moon so if 30ppm is low enough I will just get a nighthawk.

    Just want to correct myself, turns out there is a way to get a reading down to 10ppm with the nighthawk. it wont show it but if you hit peak button it will show as low as 10ppm.

    I just ordered one, it was either the nighthawk for $28 down to 10ppm or spending $130 would get a good meter that goes down to 1ppm, I didnt think the extra $100 was worth it to get down from 10 to 1ppm. I figure if its under 10 its likely not an issue anyways.
    mattmia2
  • JoeDi
    JoeDi Member Posts: 43
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    I got the Nighthawk and the manual confirms its most acurate 30ppm and up but can show levels as low as 11ppm with the Peak button.

    I put the meter right next to my boiler (1ft from the ground, not sure if that matters, iirc co doesnt rise or fall) and no reading at all. i tried moving it to a few places but nothing.

    I know its not really definitive but my guess is I dont have an exhaust gas leak.

    Is there any specific places i should place the nighthawk to try and get a reading?
  • mattmia2
    mattmia2 Member Posts: 9,653
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    I don't think it is that you have a leak per se but that the vent isn't drawing so well. It might only happen under certain conditions for example when the boiler hasn't run for a while and the chimney is cold so it has to heat all that mass to get air moving up instead of down. If it is burning cleanly there will be very little CO in the products of combustion.
  • JoeDi
    JoeDi Member Posts: 43
    edited December 2020
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    mattmia2 said:

    I don't think it is that you have a leak per se but that the vent isn't drawing so well. It might only happen under certain conditions for example when the boiler hasn't run for a while and the chimney is cold so it has to heat all that mass to get air moving up instead of down. If it is burning cleanly there will be very little CO in the products of combustion.

    It seems to happen every time the boiler runs though, I get a clear doubling of Co2 when the boiler runs, then it disipates to normal and then doubles again the next time it runs.

    Here is a graph that shows the rise and fall throughout the day:



    full size graph: https://i.imgur.com/jlytgfj.png
  • JoeDi
    JoeDi Member Posts: 43
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    I've been putting the nighthawk in various locations very close to my boiler, i even put it directly underneath the open exhaust box. I am not sure what its called but the box that comes off the back of the boiler that is wide open on the bottom that connects to the pipe that goes into the chimney breach.

    I've got zero reading, not even the low 11ppm level it can detect when sitting directly under the exhaust box.

    So I really think my rise of CO2 is not from exhaust gas escaping the system somewhere, or you would expect to see at least some CO I would think?

    So perhaps my rise in CO2 is normal from the boiling of the water? I really dont know what else it can be.
  • mattmia2
    mattmia2 Member Posts: 9,653
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    Others that do combustion analysis all the time can comment, but if it is burning cleanly I wouldn't find a couple ppm in the undiluted exhaust unusual and once the small part that dilutes with the air around the boiler it may be undetectable. You could also use a candle or a smoke pencil to see how the air is drafting up the draft hood (the open box on the back of the boiler). If it is drawing strongly it probably isn't the venting, if it just kind of lazily rises up a little then you probably have issues with the design of the vent system.
    JoeDi