noisy pipe when w/c fills

[kay-jay]

Hi

went to look at a job today, details as follows

1) all cold services mains fed
2) noise like a foghorn when toilet flushes and fills
3) slight vibration on wc inlet feed while noise is happening
4) feed pipe to inlet valve is a flexi
5) no new installations been done recently
6) property is vacant, and problem seems to be worse than when previously occupied
7) w/c cistern fills fast so no restrictions causing the noise.
8) i'm the second plumber to visit (first one did nothing)
9) inlet valve is a bottom entry plastic ball valve assembly
10) unable to tell what part of the system the noise emanates from

any ideas as to what the problem could be?????????

i'm thinking of replacing the inlet valve to see if that fixes it, but i'm reluctant to suggest a course of action to the customer without being more confident of the outcome.

thanks

KJ

 

[Henno82]

Hi Kay-Jay

if it is a new noise the the most likely problem will be the inlet valve it is either this or there are some loose pipes set behind somewhere which could be causing it, but cheapest and easiest thing to check first would be the inlet valve if it is not then at least you have eliminated something.

 

[kay-jay]

thanks henno

thats what i was thinking, my only concern was that it may not be the inlet valve because it was filling the cistern nice and fast. i tend to associate noise with restrictions of some kind.
any more thoughts on this greatly appreciated

thx

KJ

 

[kay-jay]

oh and if it helps, there is no noise when operating any other cold service, and if you open a cold bathtap and then flush, the noise is lessened.

in fact the more i think about it the more it seems likely its the inlet valve!!

KJ

 

[Plum Bob 66]

Hi KJ

Seen this one many times and its happened to me on a few occasions, try changing the diaghram on the inlet valve and the problem should sort itself out.

Regards
Plum Bob

 

[kay-jay]

diaphragm? is there one on the inlet?

its a diaphragm flush mechanism but thats seperate.

KJ

 

[Plum Bob 66]

If its a ball valve, say a part 2 or torbeck equivelant you should be able to screw off the front to reveal the rubber diaphram inside, apparently over time these get pitted with tiny little holes with casues the reverberating along the pipes

Bob

 

[kay-jay]

cheers bob i'll give it a go tomorrow!

regards

KJ

 

[Plum Bob 66]

No worries and good luck

Bob

 

[Gray0689]

Fit a new fluidmaster
Job done lol

 

[helpsy]

some of the valves have restrictors in them(that are changeable) dependant on what the pressure is.

 

[kay-jay]

thanks bob
i just replaced the diaphragm (i know it as a ball valve washer hence the confusion! lol) job done in 2 mins!

 

[kay-jay]

helpsy - i know that and knew it wasn't anything to do with that because the problem had just developed, therefore the restrictor was already the appropriate one for the supply. thanks for your input tho

KJ

 

[Henno82]

good to hear you got it sorted!

 

[djmbristol]

ive had this type of problem and all i did was to change the white pressure valve for a red pressure valve and been fine since

 

[helpsy]

helpsy - i know that and knew it wasn't anything to do with that because the problem had just developed, therefore the restrictor was already the appropriate one for the supply. thanks for your input tho
I was refering more to the compact float( than part 2 type with white/red orifice) that have 3 different set ups dependant upon pressure, like the torbeck adjustable height valve.

 

[Toddyplumb]

If i were you Id make it a habit when changing the washer to change the seat as well. If you look closely at the seat you may see hairline cracks at the end often a cause of the "foghorn" White seat high pressure . Red seat low pressure .