Two pipes next to water tank (combi) vibrating/foghorn sound

[wishiknewplumbing]

Hi everyone,

This sound is making me miserable, I wonder if anyone can help?

There is a loud humming/foghorn noise coming from one side of the water tank and two pipes next to it. It lasts for one to two minutes and then stops, at different times throughout the day and night. Mostly noticeable between 1pm-12am.

A ball valve was replaced above the water tank but this did not help with the noise.

Radiators have been bled. The pressure of the boiler was under 1 and that has been increased to around 1.3.

Before all these changes, the noise was occurring once every hour. I don't know which of the above actions has caused the noise to occur less frequently (between 2-5 times a day now).

Next to the water tank there are several pipes, and going into the water tank there are several pipes, too. Only two of the pipes that are next to the water tank, but not directly going into the water tank, vibrate. The other pipes either next to or going into the water tank do not vibrate. And when I put my ear next to the water tank, I can hear it vibrating inside, too. More noticeably from the side of the tank next to the two pipes that also vibrate.

The pressure on the boiler has been dipping slightly even though it was raised a few weeks ago- I was told it should stay at a constant pressure for at least a year.

The plumber has said he doesn't think it's ball valve related. The company who deal with the gas/boiler combi have not come out yet to have a look but when they were here- before the plumber- they were the ones who suggested the ball valve needed replacing. Is there any thing I can say to them to point them in the right direction?

Also, the noise does not occur when a toilet is being flushed or when taps are being opened and closed. Even when the boiler has been switched off from the mains, the vibration and foghorn sound still occurs inside the water tank and the two pipes next to it.

There are two neighbours above and next to the flat.

If it was just a few seconds, maybe I could forget about it, but it's the length of the hum- over a minute sometimes- and the loudness, that is so disturbing!

Thank you for all the suggestions, no matter how insignificant.

 

[polesapart]

Some pictures are needed here of "tank","boiler" and pipework.

If you turn off the incoming mains water at the stopcock for some hours does the noise still occur?

 

[wishiknewplumbing]

Thanks very much for the reply, polesapart. I have inserted two pictures of the water tank- the red circles marked show the two pipes that are vibrating. None of the other pipes going in and out of the water tank or next to it are vibrating. The vibration can be heard loudest from the right hand side of the water tank, too, next to the two noisy pipes. This vibration is causing the foghorn/humming sound.

Also attached- boiler pic.

Embarrassed to say I don't know where the incoming mains water at the stopcock is. I have attached a fourth pic is that the mains and is that what I should turn and how far? If that's not the mains water at the stopcock, where would I be able to find it?

Thanks again.

 

[HERTS P&D]

The tap in picture 2, turn it clockwise until it stops and then open the cold kitchen tap and see if the water stops.

Andy

 

[polesapart]

You do not have a combi tank. You have a conventional vented cylinder*. I guess you have a system boiler.

Stopcock; possibly/probably. I am of the opinion that every householder should know how to turn the water off in an emergency (bl**ding obvs ennit?). Worth paying someone just to confirm.

If the problem goes away with with mains water off it's most likely a ballcock issue.



* Albeit with a worrying degree of sag on the supporting base and illegal reduction of pipe size on the open vent unless these are tricks of perspective on the photos.

 

[wishiknewplumbing]

Thanks very much Andy. I tried turning it clockwise but it won't budge .

 

[wishiknewplumbing]

I am of the opinion that every householder should know how to turn the water off in an emergency (bl**ding obvs ennit?). Worth paying someone just to confirm.

Yes, you're absolutely right. My lack of knowledge is bothering me.

If the problem goes away with with mains water off it's most likely a ballcock issue.

The possibly/probably mains stopcock is hard to budge clockwise- I wasn't able to do it.

Is ballcock the same as ball valve? The ball valve above the water tank has been replaced and I have noticed a reduction in frequency of noise but not completely. The plumber who replaced the ball valve said that he did not think it was a ball valve issue but that the tanker most likely needed to be replaced (it is around 15 years old).

* Albeit with a worrying degree of sag on the supporting base and illegal reduction of pipe size on the open vent unless these are tricks of perspective on the photos.

Sorry, I am not sure what this means. Is the sag on the bottom of the water tanker and where is the open vent? Would these issues be dangerous and or causing the foghorn sound?

 

[HERTS P&D]

Get a new plumber, fit/find your stopcock and find the noise. There is another stopcock to the right of the cylinder going up to the cold water storage tank with the head missing.

Andy

 

[HERTS P&D]

Take a picture looking directly at the bottom of the cylinder. Place the camera/phone on the floor when taking the picture.

Andy

 

[wishiknewplumbing]

If the problem does not go away with the mains water off, is there any other likely scenario? The reason I ask is because the company who takes care of the boiler/water tank advised it was the ball valve that needed replacing. And the plumber who replaced the ball valve said it's likely the water tank that's the problem.


Read more: https://www.diynot.com/diy/threads/...vibrating-foghorn-sound.545080/#ixzz6Md5ChBY8

 

[HERTS P&D]

And the plumber who replaced the ball valve said it's likely the water tank that's the problem.

In what way was it the water tank?

Andy

 

[wishiknewplumbing]

Hi Andy:

There is another stopcock to the right of the cylinder going up to the cold water storage tank with the head missing.

I just went and looked to the right of the water tank but not able to see that.

Take a picture looking directly at the bottom of the cylinder. Place the camera/phone on the floor when taking the picture.

Done...

 

[wishiknewplumbing]

In what way was it the water tank?

He asked me to describe the noise, so I mimicked the frog horn/humming sound. He asked me if it came from inside the water tank and I said yes. And that's when he said that he did not think it was related to the ball valve and that if the noise persisted, the company who deals with the water tank should be concerned with the tank.

 

[HERTS P&D]

Hi Andy:

There is another stopcock to the right of the cylinder going up to the cold water storage tank with the head missing.

I just went and looked to the right of the water tank but not able to see that..

 

[HERTS P&D]

I can see the large timber on the right hand side of the cylinder but what is holding up the left?

Andy