New stopcock turns but does not shut off water

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ruggiero

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Hi,

I have an issue with my stopcock. It turns freely fully open to fully closed, but the water never shuts off.

The valve was replaced recently. I remember the plumber tested it at the time and I am fairly sure it worked on first test, but now it does not shut the water off at all. It is not stuck and does not 'feel' broken externally.

Could this be a faulty valve? It seems unlikely. Initially, we were not even sure that the pipe where the old valve was installed was actually the mains pipe, but the plumber said it was.

Any advice?

Thanks!
 
I rotate it fully clockwise and counterclockwise.

A plumber, this morning at home for another job, also tried and could not explain it.
 
Maybe it doesn’t shut off the whole house? Have seen this on occasion in some of our properties (social housing).
 
This sounds like it is a problem for the original plumber to solve - dependent on how recently "recently" is

Regards

Tet
 
CountryFan said:
Maybe it doesn’t shut off the whole house? Have seen this on occasion in some of our properties (social housing).
Click to expand...

Turn the stop tap off, then leave all internal taps, including topping up cisterns, off - waiting long enough for water in pipe, close to stop tap, to warm to ambient temperature. Next, turn a tap on, feel the pipe by the stop tap. If it cools, then the tap is passing.
 
Turn the stop tap off, then leave all internal taps, including topping up cisterns, off - waiting long enough for water in pipe, close to stop tap, to warm to ambient temperature. Next, turn a tap on, feel the pipe by the stop tap. If it cools, then the tap is passing.
Click to expand...
Fantastic idea. I will give it a go.
I need to buy a new temperature sensor. Copper has low emissivity and the infrared thermometer gives false readings
 
I am wondering if the rubber washer has come off?

Is it fitted so that the inlet is below the washer? If not I am wondering if high mains water pressure has pushed the washer off its spindle.
 
Agile said:
I am wondering if the rubber washer has come off?

Is it fitted so that the inlet is below the washer? If not I am wondering if high mains water pressure has pushed the washer off its spindle.
Click to expand...
Are you saying that the washer might come off and allow the flow? I will measure the flow again in fully closed and fully open position

1768152145627.png
 
If it worked initially then there is something wrong with it. If it didn't work initially then who knows.

Can you trace the running taps back to this new stopcock? Just to check it's on the correct pipe.
 

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