What is this clanking noise?

snootyusher

Hi-

Here is a video of a clanking noise coming from a single-pipe steam heat radiator in my bedroom: https://vid.me/nvz

It doesn't sound like stereotypical "water hammer" to me, based on a previous water hammer problem (solved by upping the pitch). It kinda sounds like some metal-on-metal grinding/shaking, as though something is loose inside the inlet itself.

The noise occurs in 5-30 minute bursts when the heat cycles on. It occurs regardless of whether the valve is all the way open or all the way closed (the only 2 valve settings I ever employ, naturally).

My super is going to try and change out the air vent, currently a Gorton D, though I do not understand why that would help alleviate the noise in the inlet.

Is my super's plan logical? If not, what might some of you suggest? Thanks in advance.

BobC

The flapper might be loose inside the radiator shutoff valve, The disc at the bottom of the shaft might be lose or broken. I suspect he wants to try the air valve because it's easy.

Bob

KC_Jones

BobC said:

The flapper might be loose inside the radiator shutoff valve, The disc at the bottom of the shaft might be lose or broken. I suspect he wants to try the air valve because it's easy.

Bob

Someone else posted this same issue recently and I think that was their issue a loose disc inside the valve. I have had this noise years ago when I thought closing the valve would actually do something...lol.

snootyusher

Thanks. I agree - switching out the vent is the easy way out, but the noise will almost certainly continue and then I'll have to bug him again, making this easy fix more difficult in the end...

Fred

Is the noise coming from around the valve area or the opposite side of the radiator or somewhere in between?

snootyusher

Fred: It is coming from the valve area. It then echoes through the radiator itself.

Fred

It most likely is a loose disc inside that valve. He probably needs to take the bonnet off of the top of that valve and see if it can be fixed or needs to be replaced.

snootyusher

So 2 questions -

1. What are the magic words that would compel him to do that?
2. Failing #1, is this something I could do on my own without much difficulty?

BobC

The radiator has to be separated from the valve so the inside of the valve can be looked at. This is not hard but complications can arise that you have to be prepared for.

Bob

nicholas bonham-carter

Or you can remove the bonnet, which could be easier than disconnecting the radiator, and moving it aside, etc. if you discover the valve washer to be bad, then you still need to remove the bonnet.--NBC

Fred

Taking that Bonnet off is certainly something you could do but if it were me, I'd let your landlord do it. You can put an open end wrench on the square nut and tap it until it frees up put the hex nut around the valve stem should also be loosened and it should be repacked or it might leak. Most plumbing supply houses will have a packing kit for the more common valves.

snootyusher

Is getting that square nut loose the key to removing the whole top section (Bonnet?) so that i can get to the disc at the bottom of the stem?

Fred

Yes it is.

snootyusher

Thanks for the guidance. I managed to get that all off. Here are some photos/video of the results:

Photo: https://www.dropbox.com/s/v56kz0m2hvkyc73/2014-11-04 18.35.48.jpg?dl=0

Video 1, where you can definitely hear some clanking at the beginning: https://www.dropbox.com/s/wn2luksgh38qgtc/2014-11-04 23.36.17.mp4?dl=0

Video 2, where at the end you can see how my finger can cause the disc to shake around: https://www.dropbox.com/s/wv15flx9g30mbst/2014-11-04 23.39.57.mp4?dl=0

So I got to this point and I have 2 more questions...

1. Is this normal behavior?
2. If it's not normal, how do I actually fix it? I took the bonnet out while the valve was fully open. Should I be tightening the bolt that's holding the disc on at the end of the stem?

BobC

Tighten it up if you can. How old is that valve, it looks new.

Bob

snootyusher

Not sure how old it is...doesn't look particularly new.

Sorry to be a bit dumb on this, but what exactly should I be doing to reduce the noise?

I'm not sure if the disc should be further up the stem, or further down it, or something else entirely. The nut at the end of the stem seems to be on there pretty firmly.

Thanks

Fred

I just looked a a couple new valves that I have on hand. They both are loose and rattle like that too. That is by design to let that disc seat itself when you close that valve. If you actually think that that's the source of your noise. unscrew that nut that holds the disc on and remove the disc and put the valve back together (without the disc). If it does not rattle when the heat comes on, then you'll know that is the source of the noise. If it still rattles, the noise is coming from something else. That disc is used to close the steam off from the radiator so you should not have a problem testing it as I describe. Just make sure you have that bonnet back on before the steam starts up (With or without the disc)

BobC

That disk should just move up and down as you crank on the handle, this disk should not flop around. If it it does and the nut is frozen in place it may be hard to fix it without destroying the valve.

Bob

Fred

Bob, I have new valves and that disc is on a pivot that allows it to flop. I'm sure so that it seats properly when closed.

BobC

My valves are all very old but what you say makes sense.

Does it look like that flapper is on a swivel? How much pressure is this system running at?

Bob

JStar

For temporary relief, just take the gasket assembly off of the vlalve stem.