Loud clicking noise every night

jjmcna10

I live on the second floor of an 100yr 3-family house in Boston. We have 5 radiators that are fed from a steam boiler in the basement. The radiator in my bedroom, which is the furthest away from the central pipe leading downstairs, emits a loud ticking or clicking noise whenever it turns on. I have a video of the noise it makes but not sure I'm able to post here. It wakes me up almost every night and I've resorted to cranking the heat up before bed, turning it off and waking up freezing. The radiator is pitched correctly and I've already tried a new air vale (vent rite #1). Is there any solution out there? I've spoken to a few plumbers over the phone who said there's unfortunately nothing they can do.

ethicalpaul

How far apart are the occurrences of the "ticks"? Has steam reached the radiator when the ticking starts? How soon after the steam arrives at the radiator does the ticking start?

You can tell steam has arrived at the radiator when the valve gets "steam hot" (too hot to hold onto for even 1 second)

jjmcna10

@ethicalpaul The clicks are about 4-5 seconds apart. The steam seems to be reaching the radiator and then then the clicking starts.

Here's a short video of the noise it makes
https://youtu.be/aKzjxzM3nQI

ethicalpaul

I have one that is doing this. It comes down to two possibilities:

1. Expansion of the radiator joints
2. Water hammer caused by steam coming into contact with cool water

I think yours is #2 but I'll be interested to see what others think.

How is the level of your radiator when measured with the level lying on the top from side to side? It should slope slightly toward the valve side. EDIT: I see you said it was pitched correctly. So it is definitely pitched toward the valve side? (the pipe side, not the vent side that is)

kenlmad

It sounds like gaseous steam and liquid water flashing or collapsing in a fight to reach instantaneous thermal equilibrium.

mattmia2

Is the valve open all the way? Does it happen the whole time that it is heating or only until it gets hot?

ethicalpaul

kenlmad said:

It sounds like gaseous steam and liquid water flashing or collapsing in a fight to reach instantaneous thermal equilibrium.

Indubitably, a distinct possibility old bean, wot wot?

jjmcna10

@ethicalpaul It's pitched towards the the pipe coming out of the floor, in other words the side with the adjustable air valve is slightly higher than the side with the connection to the floor

jjmcna10

@kenlmad I no do so good in school. Can you rephrase this for a layman?

jjmcna10

@mattmia2 the valve is currently open all the way and the clicking last for about 2 minutes during the heating up process. It then stops clicking and the radiator continues to get/stay hot

I've noticed the vent rite #1 sometimes sucks air in and other times pushes air out. From what I've read this is correct, though I'm clearly no expert

JUGHNE

It sounds like mild water hammer to me.
Perhaps raise both ends of the radiator which will raise the pipe under the floor, which may have some water pooling in it.

kenlmad

jjmcna10 said:

@kenlmad I no do so good in school. Can you rephrase this for a layman?

Sorry for my earlier verbose comment. I was referring to the root cause of the knocking sound (aka water hammer) as others have stated.

If the vent is sucking in and blowing air out (aka panting), that is another sign that there is accumulating condensate somewhere in the supply pipe. In Dan H's steam books, one of the solutions to try is to slow down the radiator's venting. Dial that radiators venting level from 8 to some lower value. Slower venting reduces the steam velocity and reduces the rate of condensate water being generated which may allow the water and steam to pass by each in the shared pipe less violently and more quietly.

Fred

Just as an experiment, try sliding a piece of plastic milk carton under each leg and see if the noise stops. It is possible the radiator is expanding as it heats but is stuck to the floor and can't slide as it expands.

EdTheHeaterMan

When the car has a rattle in it, I just turn up the radio and it goes away.
Not the kind of answer you were looking for, I know. But after you have lifted the radiator with some 1/2" wedged under all 4 legs and you have adjusted the air vent from 8 to 6 and the sound does not go away, try saying "Alexa... White noise"... or something like that.

ethicalpaul

jjmcna10 said:

@ethicalpaul It's pitched towards the the pipe coming out of the floor, in other words the side with the adjustable air valve is slightly higher than the side with the connection to the floor

Thanks. How much higher? I see no shim or lift under the vent side, that would make me feel better.

lovely radiator though

dabrakeman

Hopefully raising your radiator fixed your problem for you. Although I was aware that this would be the likely fix in my case reading your post finally inspired me to do something about mine. We had one radiator with identical behavior to yours in our family room. Since it was not in our bedroom there wasn't the sleep deprivation incentive so I procrastinated for about a decade but after reading your post I finally got motivated and got the 2x4 out and jacked it up about 3/8". Ticking gone. Plenty of reasons why a radiator may need to be raised. In this case over the ~130 years the legs start sinking into the original floor a bit. Another in my house I will tackle next is in a room where the floors were sanded and refinished so probably lost a 1/4" of height or so there.

ethicalpaul

That’s cool @dabrakeman congrats! Mine is in the living room too so I’ve procrastinated it too. 

But I have a different problem that makes me procrastinate it also. And that is this radiator is directly tied to my main so I can’t raise it without raising the entire main.

and even if I did that, the angle wouldn’t really change. So I have to repipe it. I’ll make a thread for it when I finally start cutting

dabrakeman

@Ethicalpaul (fellow procrastinator) If a straight shot from the main then yes I can see the issue raising. Mine has a 2-3 foot horizontal connecting into the riser to the valve and that horizontal connects to a 25ft runner so I had lots of flexibility. Curious though, where do you think the water is collecting if you have no horizontal section of pipe anywhere between the main and the valve? If in the radiator itself then you still might be able to give it a little more pitch from the far legs?

ethicalpaul

Here it is. The red arrow is the direction of steam flow. The 2” main turns toward the camera. The other leg of the tee that goes left is the radiator runout. So the pitch of the pipe continues down as it goes left. The radiator is directly connected to this short vertical, it’s not a correct piping.

So I suspect there is water pooling in the blue circle.

I want to remove that 2” part left of the tee, put a reducer on the tee, and pipe a 1-1/4” swing joint with correct pitch downward to the main

EBEBRATT-Ed

@ethicalpaul

That might work but I wouldn't do it.

I would plug or cap the tee. In the pipe coming toward the camera I would cut a section out and put in a new tee tilted up on a 45 (if you have room) otherwise just pitched up and then elbow over into the riser

ethicalpaul

Thanks @EBEBRATT-Ed! But now I feel really bad for hijacking the thread. I'll make a new discussion when I get close to action.

adi_b

I have this same problem! I've tried pitching it and making sure the pipes aren't rubbing against the wood floor. Almost at my wits end, really hoping it's not expansion noise..

EdTheHeaterMan

A second hijacker
WOW
@adi_b
You may want to post some pictures of the pipe you believe is the problem. But you may also want to start your own discussion.
We are all looking forward to helping you

Yours truly,
Mr.Ed

PS you can reference this discussion by copying and pasting this in your discussion. https://forum.heatinghelp.com/discussion/182596/loud-clicking-noise-every-night... but it is better if you tell your own story.