Sink mixer tap discharging water

[HBSPlumbing]

We are in an ongoing dispute with a customer in relation to a Bristan mixer tap that was installed within the last week. At non-regular intervals, the tap is discharging an amount of water (equivalent, according to the customer, to 5 tablespoons of water).

Now he is convinced that the ceramic discs are passing water, but our argument is that the small amount of water left in the tap can siphon out after the tap has been turned off, due to a number of different variables such as change in atmospheric pressure or something along those lines.

He is now saying that the tap is faulty and we should send our plumber and fix the "problem" but we think that there isn't one, and Bristan are saying the same thing.

Has anyone else had similar experiences?

 

[seco services]

yes i have to agree with you on the atmospheric pressure.
seen this happen a few times with kitchen monoblocs with the long spout.
i have shaken the spout after running the kitchen tap to release any water left in spout and it didn't spurt no water out later on. as none was left in the spout.

 

[powell30]

If the ceramic plates were letting by then the drip/run should be constant. Hmmm, never had one that lets by 'occasionally' unless when it is opened and shut the plates are not moving over far enough.....but then the run would be constant. Does it happen once after use or is it a constant thing? ie set time period and then a drip run?

 

[HBSPlumbing]

If the ceramic plates were letting by then the drip/run should be constant. Hmmm, never had one that lets by 'occasionally' unless when it is opened and shut the plates are not moving over far enough.....but then the run would be constant. Does it happen once after use or is it a constant thing? ie set time period and then a drip run?

Well this is what we are trying to establish. He seems to think that it is a constant thing but we have instructed his to leave a cup under the tap overnight and see what is left in the morning, but it wouldn't surprise me if he sabotaged the experiment.

And referring to your first point, yes we agree that if the ceramic discs were damaged then there would be a constant flow or a drip rather than this discharge in one go.

 

[HBSPlumbing]

yes i have to agree with you on the atmospheric pressure.
seen this happen a few times with kitchen monoblocs with the long spout.
i have shaken the spout before after running the kitchen tap to release any water left in spout and it didn't spurt no water out later on. as none was left in the spout.

yeah that is exactly what the tap is:

He says it is "school-boy physics" that water can not run up hill but he can't seem to grasp what we are trying to tell him.

 

[TicklyT]

You could try demonstrating by removing the aerator from the end of the spout. The flow from the tap will probably look awful, and go everywhere, but it should stop the dribbling.

In my experience, some water is released when an air bubble forces it's way up through the surface tension of the water in the relatively small holes in the aerator, breaking the vacuum that is holding the water in the spout.

I would say your customer should have paid more attention to his physics lessons when he was a schoolboy if he doesn't understand the concept of surface tension or the principles behind the operation of a syphon.

 

[HBSPlumbing]

You could try demonstrating by removing the aerator from the end of the spout. The flow from the tap will probably look awful, and go everywhere, but it should stop the dribbling.

In my experience, some water is released when an air bubble forces it's way up through the surface tension of the water in the relatively small holes in the aerator, breaking the vacuum that is holding the water in the spout.

I would say your customer should have paid more attention to his physics lessons when he was a schoolboy if he doesn't understand the concept of surface tension or the principles behind the operation of a syphon.

Haha, well thanks for replying but I have just had a call from Bristan saying they have spoken to the physics master himself and have explained it in a way that even the most simplest of minds can understand and he has accepted their reasoning. I could foresee a headache arising from this one but Bristan and people on here have been more than helpful!