Humming Noise from Gas-Fired Hot Water Boiler Zone

bsewards

My home has an older boiler, Teledyne Laars JVS-125C (30 psi max, 103k ctu/h heating capacity). I had it serviced/fired up last month and didn't notice that the basement zone circulator makes a continuous 3 second rising humming/vibration noise that I can hear throughout the house (3 zones, 3 levels, 3 circulators). I believe it's the basement zone because the sound only occurs when I turn the basement thermostat up to activate the zone.

I was going to start by trying to bleed the air out of the basement zone, but the hook up is baseboard (1st and 2nd level are cast iron radiators) and I can't seem to find a bleeder valve near the baseboard pipes or a drain above the circulator shut-off valves. The basement zone pipes are a bit smaller than the other 2 zones, but the circulators are the same (except the basement ironically has the newer model taco 007-f4, whereas the others have the taco 007-f3).

Here is a video of the noise:

https://photos.app.goo.gl/VVknSTwwsaJoD6pq8

And here's the whole set up:

Should I even bother trying to bleed the air out of the basement zone? I could also try adding one of those auto-bleed valves if necessary?

EdTheHeaterMan

The reason most heaters Hummmm is because they forgot the words.

Try placing the sheet music on the ground in front of the boiler and see if that stop the humming

Big Ed_4

Run the basement zone for a while , see if clears up . It could be just summer grit …

HVACNUT

If the basement zone circulator is the one closest to the chimney, then there's no purge valve like the other two zones have.

Are there bleeders on the basement emitters?

NO air eliminators. You have an "air control system".