Wining/Screaming H&C Taps

[JSPM]

A client has had a combi boiler installed downstairs. When the bath hot tap (monoblock type with a large outlet) is turned on a wining/low screaming noise starts at intermittent times.

The hot and the cold taps in the kitchen make a similar noise when turned on, whether it be fully open of just partially. The noise is alleviated on the cold when the outside tap in turned on briefly.

Any ideas?

Many thanks

Dave

 

[Paul Cockhill]

Have you checked that the jumpers are ok

could be a case of just changing them or replacing the washers

 

[stevetheplumber]

A client has had a combi boiler installed downstairs. When the bath hot tap (monoblock type with a large outlet) is turned on a wining/low screaming noise starts at intermittent times.

The hot and the cold taps in the kitchen make a similar noise when turned on, whether it be fully open of just partially. The noise is alleviated on the cold when the outside tap in turned on briefly.

Any ideas?

Many thanks

Dave

is it possible the preasure is to high ?

 

[Bernie2]

Sounds like too much pressure. The taps probably have a high resistance factor causing noise. Are the maximum fitting velocity and flow rates exceeded?

Without rolling out figures, if you increase pressure and flow in a system, beyond certain limits it will become noisy.

Pipes are not smooth when you get down to microscopic level and the water passing over these rough surfaces cause not only friction, but if the difference is enough you get noise.

On copper pipe excessive water speed attacks the inner surface protective film of the pipe and can cause erosion.

A tap is probably even worse. When they make a tap they usually cast it in sand, which is very hard to machine smooth in certain areas.
In point, if you look inside a tap you will see what I mean. So fast moving water moving over the rough areas could be a possible source of the screeching noise.

Turning the flow down does seem to help. Fit a cheap ball of flow valve and try that, just turn it down until you get a good balance between flow and noise. Other than that you can fit a pressure reducer or even get a tap insert type.