Boiler Trouble - House Vibration

HVACNUT

Is it safe to say at this point the 11:00 thing is an unintended deflection? Otherwise this would be easy.
What timer is set for 11:00 always? But not always.
A 7 day programmable thermostat with different 11:00 settings?
Irrigation timer with rain sensor?

If "suddenly the entire house literally vibrates, it shakes. Almost like a car just ran through the first floor."

For 1-2 seconds, (which is a long time) it shouldn't be hard to find.

Try to narrow it down. Insulate pipes and secure loose hangers. Check anything that has a timer or schedule.
We're not even positive its originating from the heating system right?


Gimme 3 hots and a cot and I'll find it for you. And bottomless coffee. Because it would drive me nuts if it was my house.

JUGHNE

Assuming you have no leaks in your system, you could shut off the water supply to the boiler. Many systems operate with the supply off, though they should have a low water cutoff safety.

You could try that for a couple of days see what happens.

Also your zone valves should be open before the pump starts.


Again what pressure is on the relief valve label and on the boiler label?

1 or 2 story house?

pabadear

> @Zman said:
> (Quote)
> Are they set to change the temp at the same time you hear the noise?

Sorry didn't see this till now. The thermostats don't have anything set for 11am but they are both on automatic to kick in if the interior temperature drops below a specific number.

pabadear

> @Alan Welch said:
> What are the temperature settings under the cover of the gray control on the front of the boiler? Maybe the high limit isn't working.

This is what's under the gray control inside - not sure what I'm looking at to be honest.

pabadear

> @JUGHNE said:
> Assuming you have no leaks in your system, you could shut off the water supply to the boiler. Many systems operate with the supply off, though they should have a low water cutoff safety.
>
> You could try that for a couple of days see what happens.
>
> Also your zone valves should be open before the pump starts.
>
>
> Again what pressure is on the relief valve label and on the boiler label?
>
> 1 or 2 story house?

30psi rated pressure relief valve. Picture attached. The house is a 2-story and a basement.

HVACNUT

Shut off the power to the boiler first.

There's a temperature dial on the right side of the aquastat, to the right of the white paper.

What's the setting, and does it match the reading on the gauge? Check this by raising the heat and letting the boiler run until the burner (limit temp) shuts off.

pabadear

So here's something interesting that just happened. At exactly 11am today, sure enough the rambling/vibration occurred. Same magnitude as I previously described and this is the first time it happened since March 13 which prompted me to post here.

At 11:02am, a friend of mine who lives a few blocks away asked me if I heard/felt that. I described to him what I felt and he echoed the same thing. I reached out to my neighbor directly next to me and he said his wife felt it and also compared it to an earthquake. He said they feel it from time to time and got used to it. Now I highly doubt earthquakes happen here on a regular basis so I'm ruling that out but I guess it's safe to say it's not my boiler system after all? We're always in the family room which is directly above our boiler room so that's why we assumed it came from there. But what the heck can be triggering such a strong vibration that can be felt from house to house, and in this case, block to block? My friend who felt it said they felt it last week too so it was probably the same incident I felt on March 13. Can city pipes do something like this?

hot_rod

It could be a PRV out in the main water lines, but the timing is odd.
When I lived in a mountain community once a week they "exercised" the booster pumps on the water mains, we would see pressure spikes when that happened. I suppose noise could be related to that type of test? Contact the water dept, I'm sure they would have some interest.

JUGHNE

The water company may be cycling water pumps at that time.
Perhaps another pump comes on on the opposite side of the system, applying pressure from the other end.

(Unless you live above a subway that you haven't noticed yet. )

pabadear

After a few discussions on a neighborhood forum, it seems there is a quarry a few miles out that performs planned mining explosions around 11am once or twice a week. So the rumble I'm experiencing is most likely the result of that, and explains the magnitude I've been trying to express here. Apparently people all across the town feel it to some degree, depending on how close or far they are from the quarry site. It's not even in our immediate town but the next town over but since I'm fairly close, I probably get the shock waves of their explosions. Figured I'd share to all those who have been helping. I appreciate it all - thanks!

Jamie Hall

Now that makes some sense. Good to know. Thank you.

STEVEusaPA

Well that has to be a first for The Wall

JUGHNE

So it was a Subway after all!

hot_rod

good detective work!

PerryHolzman

I'm actually a licensed blaster. My expertise is explosive metal forming and welding, although its been a while since I have used my license for this (I keep the license current due to the difficulty of replacing it).

Please be advised that there are very rigorous requirements for seismic and noise levels for blasting in almost all states (without very rare and special permits to exceed those levels).

Blast companies must have adequate seismic and sound level recording equipment - and must keep the records.

I suggest that you contact the quarry, and ask to meet with the Blasting company involved. Ask them to show you the state requirements (actually you should be able to find that online in your state code) and the records for the recent several "shots."

Present yourself as you are concerned and wish for them to educate you (and your neighbors - if interested) on the issue.

If they are not within the legal limits - report them to the appropriate state department. In most states they are supposed to self report anytime they exceed the legal limits. While most blasters and blast companies are decent people... there are bad apples like as in any industry.

I wish you the best,

Perry