Foghorn Noise.

[GlenQuagmire]

I've no experience in plumbing so please bear with me. I have a Franke Zurich mixer tap in the kitchen. It's 7 years old. Several months ago I noticed a slight drip starting which was from the cold. More recently, I dare not turn the cold off completely as when it gets to a certain level, there's a whistling siren sound. Turn it off any further and there's this horrendous foghorn noise. Occasionally this racket happens out of the blue even when the tap isn't being used and just sitting there trickling. Then I have to quickly turn the tap on full to stop the noise. The house almost vibrates as it's so loud. The tap's cold water is fed directly from the mains and the mains stopcock is just below, in the cupboard under the sink. Any suggestions greatly appreciated. Thank you.

 

[Agile]

Do you have a particularly high mains water pressure?

I presume that your hot water comes from a combi boiler or an unvented cylinder ( i.e. at mains water pressure! ).

At first sight the tap washer may have become worn and need replacement.

 

[just pumps]

Ball valves in cold water tank if you have one and flush valves in toilet cisterns not fully closing can cause the noise.

 

[JohnD]

The tap's cold water is fed directly from the mains

looks like Agile has it.

 

[Hugh Jaleak]

'Water Hammer', noise is created by a loose washer or 'jumper' in a valve vibrating. Similar action to the Reed in a Wind Instrument. Noise is amplified by the water and pipework.

Try and work out which valve it is, if it's the stoptap, winding it in a turn or so may help. If a Ballvalve, I'd replace it and see if that improves the issue.

 

[Elkato531]

Replace the ceramic disc valves in the tap. I have known these to vibrate and cause horrendous noise.

 

[dilalio]

If you live on a ship, it might actually be the foghorn!

 

[jeff the gasman]

What Elkato said.

 

[GlenQuagmire]

Thanks very much to everyone. Sorry I'm only getting back now. In answer to suggestions and questions. I just have electric heating. The mains stop valve under the sink is stuck dammitt so I'm trying to release it to see if turning down the pressure will help. Two other things of note. I have noticed recently an occasional drip from the cold water tank overflow outside. And if I turn on the outside tap, the kitchen tap goes crazy with the foghorn noise. Any further thoughts greatly appreciated. Thanks.

 

[dilalio]

Main stopcock needs servicing or replacing.

 

[Elkato531]

As I said in post #6, replace the CD valves in the kitchen tap.