Loud buzzing on steam gas boiler

MyName

Any thoughts on what might have caused this problem? My Peerless gas steam boiler (one-pipe system) is young, 4 years old. I turned off my thermostat mid-June. The service tech last month did the annual check-up. A service tech returned last week when the boiler would start and then immediately stop repeatedly. He said the grounding wire was disconnected. He connected that and filled the water a few inches above the fill line on the sight glass saying that was good to do at season start. That was Tuesday. The boiler ran a little bit with the cool nights.

2 days later early morning when the heat came up, a huge buzzing filled my house. I turned the thermostat off and the buzzing stopped. I tried again a half hour later, and the boiler started normally, and about 10 minutes later the loud buzzing started again. So it sounds like once steam gets going, the buzzing starts. It has some sound of metal clanging.

Later that day a service tech arrived and everything was fine, no buzzing. It is now 3 days later and everything is still fine. The tech had no idea what caused the buzzing, guessed maybe some dust between some magnets that is now gone. He did drain some water to the level line. I'm wondering if something blocked a main pipe vent that then loosened up. Like steam could not escape and shook everything. I feared it could explode so did not go into the basement.

Here is a short video of the buzzing - I walk from my living room (TV on but can hear buzzing) and open the basement door so the noise is louder. In person, it is much louder than in the video.

https://youtube.com/watch?v=2oUhCVk_v7k

Zman

Did the tech verify correct operation of the PRV (pressure relief valve) LWCO (low water cutoff) ?
If those 2 devices are functioning, it should be safe to go into the basement and find out where the noise is coming from. It sounds electrical to me. Does it stop and start immediately with the t-stat?

MyName

What I know is this was one of the senior techs from the heating company. He spent a lot of time checking everything out. He turned on the boiler and stayed with it for about 15 minutes and nothing was wrong. The problems from the morning did not occur.

In the morning, when there was this problem both times of turning the heat on, the boiler would fire up normally. Then about 10 minutes after would start buzzing. Since then, all is normal. I would like to get a better feel if you might know what the problem could have been, should the problem return.

Zman

The noise sounds electrical. It will be hard to pin it down from upstairs.

Steamhead

I'd say either the transformer or relay, or possibly the gas valve. It may be a simple matter of tightening a loose mounting screw.

HVACNUT

@Zman and @Steamhead. Does the Peerless use a fan center control relay inside the burner cabinet? Definitely sounds like the G.P. relay if that's what's used.
I recently had a bad relay in a new fan center I'd just replaced on an oil furnace with A/C. Same noise. Extremely loud buzzing. Drove me nuts thinking I wired something wrong. Popped in a new relay only. Problem solved. Bad relay, out of the box.

Steamhead

Not sure if it came stock with such a relay- it doesn't show in the parts list- but fan centers are often used to power and isolate digital thermostats so it may have been added.

HVACNUT

@MyName If it's a 63 series, then checking the manual, it does have a fan center control relay for switching.
Ask the service tech to check/replace the DPDT relay (24v coil) in the burner compartment.
You shouldn't need the whole fan center, just the relay. It's a common part.

MyName

Thank you everyone. You've given me some great ideas for my service tech. Yes, Model No: 63-03-SPRK-SP.

HVACNUT

> @MyName said:
> Thank you everyone. You've given me some great ideas for my service tech. Yes, Model No: 63-03-SPRK-SP.
>
>
> NP. The relay takes about 10 seconds to replace. Just pull out the old and push in the new. Let us know how you made out.

MyName

I have not used the boiler since the above. Today I did. The loud buzz happened again. I went into the basement and felt a vibration touching the body of the gas steam boiler. Seems on the right side where all the "stuff" is, like low water cut-off. The radiators were hot, so the boiler was cranking up a while, it starts I think at about 5 a.m. to get up to heat at 6 a.m.. The buzz started about 6:10 a.m. I turned the heat off. I turned it back on about 15 minutes later. No buzz, and it is an hour later.

I put in a service call and asked they replace the relay as mentioned here above. It is a "no heat" call. Last time, the buzz did not happen when the service tech was here, so I asked they do this low cost simple fix anyway, copied detail from above into the email for service.

Any other thoughts, let me know. It is flaky, something is loose if stopping/starting the boiler stops the buzzing. Last time it took twice doing that to stop the buzzing.

j a_2

Take a picture of the relay in question

MyName

Not sure what you actually mean, I'm just a home owner. I assume the relay is inside the body of the boiler. Are you saying once they remove the old and put in a new one, take a picture of the old one to share with here?

j a_2

The front cover should just lift off,lift it up and off and snoop a picture.

j a_2

Take a picture of the gas valve and the spark control unit. Close up if you can. As well as the wiring...

MyName

Will do. When tech guy arrives I can video all those parts with him also checking each part (again). Hoping he also just replaces the relay. The video will be shared here, in case you guys spot anything else that the tech guy does not.

j a_2

Oh sorry my intention was not to question the on site tech. I was trying to help give a explanation and easy fix.

j a_2

It happens sometimes on that series and simply replace the fan unit assembly. I see if I can get you a part number....best I can come up with site ubseen

JUGHNE

You did get the buzz after the boiler started to make steam. It is possible that the water level dropped and the auto water fill came on.

Ask the tech what type of auto water fill valve device you have.
If electric there is sometimes a manual button to activate the fill.
Pushing that would activate the water valve.

These involve relays and solenoid valves, which could buzz intermittently if active.

MyName

The water level was ok, just above the fill line. No buzzing on any outside "thing".

MilanD

Sounds to me like our LGB electronic igniter / pilot proving control module - on the gas valve train. Our does it intermittently, similar buzzing, but it's not quite as loud. Take off the door/cover and you should be able to hear where the buzzing is coming from once the cover is off. I am unfamiliar with your particular boiler, but ours too is intermittent. fwiw...

MyName

Just before I read your post, MilanD, the buzzing started again! The tech guy is here playing with the boiler for a while. So I ran down to the basement and he told me it is the gas valve buzzing. I read him your info. He explained, with the part taken out, there is a magnet in it that was not closing properly at times, dust or whatever. Now he is testing further down the line to see if something else might be a problem.

Anyway, we are on track now. Thanks.

MyName

Along with replacing the gas valve, the tech service man also replaced the control that powers the gas valve. Said it may be that the power was not consistent and caused the gas valve magnet to not close properly at times.

JUGHNE

Perhaps he meant the gas valve would not open correctly at times.
It is to close properly when power is removed.

MyName

I'm sure he said it correctly. My words are based on memory, what that is worth. Today NO BUZZING. So happy.