Singing Boiler

[rokosz]

Hi folks, its been a while since I've been on here. its good to be back in one way and well, maybe not if my boiler is dying.

Weil-Mclain vintage (20+ yrs) gas boiler for winter heating. Was away, came home, temp inside was 55, bumped the therm to 62, heard the unit in the basement kick in as usual. Went down to the basement a minute or so later and heard a sound I know I don't normally hear from the boiler.

It was a perfectly rhythmic, maybe two or 3 beats per second of a sound that's kind of cross between a whistle/tweeting bird and a cricket. I heard it easily from about 20 ft away. Its coming from inside the boiler, seems like upper back corner. There's, what I presume is, a water pump on the outside of boiler/box. The sound is definitely not from there unless its a ventriloquist.

Now, after a few days of maintaining an indoor temp, when the boiler kicks in the tweeting doesn't seem to be nearly as loud as it was. (I now only hear it when I'm much closer to the boiler)

So, a concern? the fact it seems to "work its way out" over time makes me think of lubrication. But of what? I'm hoping you folks might have some more/better ideas of what's going on. And perhaps avoid an embarassing service call for a boiler tech.
thanks

 

[pjones]

I would put your hand on the body panels and see if the nose stops when pushed. Careful though. They may be hot.

 

[rokosz]

aha! thanks, I hadn't thought of sheet metal -- and perhaps cold metal squeaks more. I was down last night _trying_ to hear the birds but could barely make out anything. I'll grab an oven mitt and...

 

[bud16415]

aha! thanks, I hadn't thought of sheet metal -- and perhaps cold metal squeaks more. I was down last night _trying_ to hear the birds but could barely make out anything. I'll grab an oven mitt and...

I have had forced air systems my whole life, but work had steam heat and as a kid I remember a lot of hot water systems. During the first week or so after being shut down I remember the trapped air working out of the systems and them clanging or singing. Maybe yours is similar as it seems to be fixing itself.

 

[Gary]

I have a boiler system. If I had to guess, and that's pretty much what I'm doing, I'd have to say Bud is probably on the right track.
Ours made noise in the fall when it first started up. Since the tornado a few years ago, we have replaced just about everything on the system including new boiler. Doesn't make noises much anymore. I attribute that mostly to installing new bleeder valves on all the registers. The old ones had been in use many years and didn't seal completely anymore. So they would drip a little in the winter (but it would evaporate from the registers heat) just left deposits evidence behind. Then in the off season they would let a bit of air into the system. Also the pressure valve that kept the system filled had seen it's better days and wouldn't keep enough pressure in the system, allowing the bleeders to let that much more air in. I would speed up the process by going around every fall, manually bleeding each valve to let the air out. Since installing the new parts I haven't had to do that anymore.

 

[billshack]

is it a steam boiler or a hot water boiler?

 

[Gary]

O.K. different animal than mine.

 

[rokosz]

natgas/hot water. turns out it is at least the sheet metal. even the warmer quieter tweets are suppressable if you press the metal. On the other hand, thats a good idea to check the rads for valves and air. Haven't touched them in 6 or 8 years

 

[billshack]

Have you checked you circulation pump? if you have an armstrong s-25 i would say your spring coupler id gone . also when i do noise checks i walk around and put your hands on everything .