Burnham ES2-5 strange noise

pal379

I have a gas fired Burnham ES2-5 boiler. Installed June 2016. December of 2024, I’ve noticed a sound like water is splashing inside when the unit is running, and when’s it off, it slows down and stops. I called the installer/plumber to take a look, he said no signs of leaking anywhere, the burners are clean and the flame looks correct.

At first he thought it was water coming back down the chimney so we left the damper opened and ran a few days to see if that would help. It did not.

so I decided to sit behind the boiler when it ran, I saw the damper open, and watched the unit run. No sign of water coming down the chimney. Also that sound like it’s coming from the heat exchanger/ block not from the chimney area.

so while the unit was running, and not running, (while making that sound), I stuck my phone to record it.

can you let me know if the heat exchanger looks normal or is it dirty?

https://youtube.com/shorts/JK3KlrmCU...fTGwPKeKREgWJr

https://youtube.com/shorts/6Ydhzp1hc...3Z9xTSTmbarijb

https://youtube.com/shorts/zYcY89BI_5Y?si=eqah_iDMElGkhc_1

Thank you.

tcassano87

so with coming call for the boiler, no heat or domestic HW calls, it’s making that crazy noise?

Have you contacted Burnham?
Never heard of a sound like that not really sure what it could be but do you have fresh air coming into that room?

pal379

hello, the unit will call for heat, and after a few minutes of getting hot, it will start making that sound. Then when the boiler shuts off, it’s will continue that sound for few moments later, like it’s slowing down.

I tried calling burnham a month ago, with no response, I guess I will try them again.

Is this noise considered kettling? Should I try a boiler cleaner?

I had 2 plumbers come out who were stumped. They both had the same thing, just run with it. One plumber lowered my boiler temperature a little bit, he thought it was maybe hot enough where it was making steam. But that didn’t solve anything. The boiler is running fine, no leaks anywhere. the other plumber had me run with the damper opened for a weekend to see if that fixed any issues but it didn’t either.

I can live with the noise, my wife on the other hand, not so much! she says it sounds like people trapped in a submarine.

The noise happens on any zone. I was wondering if air was an issue but all my zones are getting hot as well as my water heater.

pal379

The 2 plumbers were saying run with it to save me money. They said the flame looks good, the burners are pretty clean, the unit is pretty clean. They say it’s working. But one did recommend calling burnham and getting a rep to come out and listen to it.

Big Ed_4

My guess , there is a pin hole …

pal379

thank you Big Ed_4, should I try a boiler leak stopper?

Ironman

Did either one do a combustion analysis, check manifold pressure, or clean the burners?

Steamhead

Ironman

Apr 12, 2025

Did either one do a combustion analysis, check manifold pressure, or clean the burners?

This. Maybe the gas pressure is fluctuating?

pal379

Ironman

Apr 12, 2025

Did either one do a combustion analysis, check manifold pressure, or clean the burners?

yes, one inspected the burners, he said it was pretty clean, one had debris so he cleaned off that one. He said the flame looks good and checked my gauge with water temperature and pressure and said everything looked good as well.

Nothing more than that. I put a call into Burnham on Thursday. Hopefully I get a response from them.

before the boiler makes that noise, as it’s warming up, it almost sounds like air is venting internally before that annoying sound occurs.

The noise sounds like it’s coming from the left- back side of the unit.

neither checked my gas pressure.

Thanks for the feedback. I appreciate all of it.