Hi there,
I've got what I think might be a 1960s-ish AS boiler. It is a thing I've come to have a mostly-love relationship with, after learning bits about how it works and how to maintain it (as much as I should or can). I just had a plumber out the other day because there was a pretty awful burn smell on startup. Did a major clean of loads of soot, and on startup after that, there were huge yellow/orange flames and rollout (I think I'm using the correct terms??) and still a smell. The plumber was very surprised, and suggested I get the masonry chimney checked as a next step, and we turned the thing back off. Chimney cleaner came out next day, chimney was very clear, and I also cleaned out the metal trap at base (that was sort of terrifying).
So, I did a little more poking around before calling the plumber back/another plumber. Found that I could remove the top cast iron part of the actual boiler, and found more soot to clean there. After that, I relit the pilot and started up--no more smell, but still major flame and rollout. Turned it back off, put in call to plumber to see if they would come back to check again, did a little research, and was able to find the gas pressure screw. I'll start by saying I know I shouldn't mess with this stuff, but I did. I adjusted the screw down until the flames were all blue and much shorter. My pilot is blue too, btw. I do not have a manometer or combustion analyzer, and I know that is the next step--the plumber who was out did not check those things, so I am going with a different one this time.
So, short story made long (sorry), I guess I'm just looking for some advice on what the flames should look like when fired up? I imagine there is no one-size-fits-all answer, and combustion and efficiency will tell me more. But--on a properly running, old, natural gas boiler, are the flames often a couple inches high when fired? Six-eight inches? Are they entirely blue, or can there be a few licks of yellow here and there? What is realistic? I felt like the really high flames were just...too high. It seemed wrong.
Thank you!
I've got what I think might be a 1960s-ish AS boiler. It is a thing I've come to have a mostly-love relationship with, after learning bits about how it works and how to maintain it (as much as I should or can). I just had a plumber out the other day because there was a pretty awful burn smell on startup. Did a major clean of loads of soot, and on startup after that, there were huge yellow/orange flames and rollout (I think I'm using the correct terms??) and still a smell. The plumber was very surprised, and suggested I get the masonry chimney checked as a next step, and we turned the thing back off. Chimney cleaner came out next day, chimney was very clear, and I also cleaned out the metal trap at base (that was sort of terrifying).
So, I did a little more poking around before calling the plumber back/another plumber. Found that I could remove the top cast iron part of the actual boiler, and found more soot to clean there. After that, I relit the pilot and started up--no more smell, but still major flame and rollout. Turned it back off, put in call to plumber to see if they would come back to check again, did a little research, and was able to find the gas pressure screw. I'll start by saying I know I shouldn't mess with this stuff, but I did. I adjusted the screw down until the flames were all blue and much shorter. My pilot is blue too, btw. I do not have a manometer or combustion analyzer, and I know that is the next step--the plumber who was out did not check those things, so I am going with a different one this time.
So, short story made long (sorry), I guess I'm just looking for some advice on what the flames should look like when fired up? I imagine there is no one-size-fits-all answer, and combustion and efficiency will tell me more. But--on a properly running, old, natural gas boiler, are the flames often a couple inches high when fired? Six-eight inches? Are they entirely blue, or can there be a few licks of yellow here and there? What is realistic? I felt like the really high flames were just...too high. It seemed wrong.
Thank you!
