loud noise and pipes vibrating when shower is on

[Laubi]

hi all,

(this doesnt happen every time so cannot reproduce it but does happen about few times a week but must be a reason I can't work out)

'Sometimes', after turning the shower on and after about 10 seconds, the pipes make a loud foghorn type sound and the cold water pipes around the house start vibrating quite bad. I have tried securing any long sections of unsecured pipes I can see with clips but nothing really changes.

The vibration stops if I turn on the cold (not hot) tap elsewhere in the house (tried different rooms with same results). I need to leave these taps turned on for a little while (say 20 seconds) and the problem goes away. If quickly turn the tap in the other room quickly on and off again, the problem stays.

I have had this issue in the past but since having the new bathroom renovated, it has been much worst. We haven't changed any pipework except plumber converted a 1m section of copper in the floor feeding bath filler taps from copper to flexi's as we wanted the T coming out in a different location. Also, we got a new shower mixer valve kit.

everything else is the same as previous.

It seems to be its the pressure too much for the pipes? any ideas on whats causing this or how to fix this would be much appreciated!!

I have tried sketching out my pipe system relevant to the shower (theres more pipes but just focused on the shower one)

 

[cross thread]

Possibly the ball valve in your cold water tank, be worth trying for the price of one.

 

[Laubi]

Possibly the ball valve in your cold water tank, be worth trying for the price of one.

how do i tell if it needs replacing?

 

[CountryFan]

how do i tell if it needs replacing?

Poor/slow filling usually a good sign. Any 1/4 turn taps on mains pressure?

 

[Laubi]

Poor/slow filling usually a good sign. Any 1/4 turn taps on mains pressure?

bathroom basin and kitchen. both monobloc mixers. bath filler is quarter turn but seperate feeds (not mono).

you mean slow filling of the cylinder I presume? only way to tell is listening?

the ballcock valve from header tank to cylinder seems to work fine in terms of isolating

 

[Harry Bloomfield]

how do i tell if it needs replacing?

If someone were to touch the ballcock arm, whilst you can hear the noise, and the noise stops - then it's caused by the ballcock.

 

[CountryFan]

bathroom basin and kitchen. both monobloc mixers. bath filler is quarter turn but seperate feeds (not mono).

Are any of them dripping/made worse with the noise?

you mean slow filling of the cylinder I presume?

Well no, the cold water storage cistern that replenishes the cylinder

only way to tell is listening?

No, it can be visual

the ballcock valve from header tank to cylinder seems to work fine in terms of isolating

Ok

 

[Laubi]

Sorry guys, noise hasn't happened for me yet. Annoyingly happened for my partner but wasn't around to test.

Just to double check, ballcock we are talking about is this one (photo) which feeds the cylinder? Forgot to mention, this was actually replaced so it's brand new as the old one had a small leak.

Are any of them dripping/made worse with the noise?

The bath filler when first installed did drip after use for a little while. But seemed to have stopped now.

Also, might be important to note is that 'sometimes' when I turn off the bath filler or basin tap, it makes the same foghorn sound ever so slightly. A lot quieter than the main issue. I assume this was a hammer reaction so wondering whether to put an arrestor in and where. But the sound is intermittent and very short and quiet.

 

[CountryFan]

No that's a Gate valve. The ballcock does feed the cylinder but is connected to the cold main

 

[Laubi]

Sorry guys. Still can time it so when it happens, I got enough time to get into the loft to check the ballcock.

But I did work out that it is this pipe which vibrates. Does this help indicate anything further or still try and get into to loft and check the ballcock first?