Kitchen tap keeps tripping RCD

[Jollymol]

Hi!
Just moved into a property, the kitchen sink tap whether hot or cold, trips out the sockets on the rcd. it needs to run for about 10 seconds and then it trips out.. I can immediately reset the rcd no issues but if I run it again for 10 seconds plus it will trip… I’m stumped, had an electrician round doing some other bits and he was quite stumped (convo only) he suggested a new circuit board is probably needed? I spoke with a plumber on the phone and he doesn’t think it will be a plumbing issue if the upstairs taps are not causing it to trip ( which they are not, nor the downstairs loo, just the kitchen sink?) just wondered if anyone else had or knew what this is? I don’t have a combo boiler but a fairly new Worcester boiler and older water tank.. no heating or hot water issues, sometimes the upstairs shower will cut out after a lengthy time?
Thanks for any suggestions.

 

[Jackrae]

Do you have an under-sink water heater, conditioner or dishwasher connection that may be the cause of the trip. If not, there is a possibility that the sink drain is somehow leaking water onto an under-sink electrical socket

 

[JohnD]

Yes, very likely a water leak.

 

[ericmark]

Leaks seem most likely, but only way is to measure, what I wonder is why the electrician was stumped? Likely no test equipment? But if he can't work it out, unlikely to work it out on a forum.

 

[JohnW2]

.... what I wonder is why the electrician was stumped? Likely no test equipment?

Maybe because ....

.... had an electrician round doing some other bits and he was quite stumped (convo only) ....

You go onto say ...

But if he can't work it out, unlikely to work it out on a forum.

... but having a 'convo' is not really any better than trying to diagnose the problem, 'on a forum', is it?

Having said that, if (as we've been told) the RCD trips about 10 seconds after a tap is turned on, but is then immediately resettable, I think it might be very challenging to get any useful results from any test equipment (even if one had it) during the very short time window during which some problem presumably exists.

Kind Resuklts, John

 

[flameport]

just the kitchen sink

Is the sink made of metal?

 

[Jollymol]

Leaks seem most likely, but only way is to measure, what I wonder is why the electrician was stumped? Likely no test equipment? But if he can't work it out, unlikely to work it out on a forum.

Thanks for your input, it was to pick the brain of a plumber or electrician that may have had similar for me to look into, money is tight? Hence the forum…

 

[Jollymol]

Is the sink made of metal?

No its not metal

Leaks seem most likely, but only way is to measure, what I wonder is why the electrician was stumped? Likely no test equipment? But if he can't work it out, unlikely to work it out on a forum.

 

[Jollymol]

Maybe because ....

You go onto say ...

... but having a 'convo' is not really any better than trying to diagnose the problem, 'on a forum', is it?

Having said that, if (as we've been told) the RCD trips about 10 seconds after a tap is turned on, but is then immediately resettable, I think it might be very challenging to get any useful results from any test equipment (even if one had it) during the very short time window during which some problem presumably exists.

Kind Resuklts, John

Thanks, just wondered if anyone had any ideas to put up as money is tight. Appreciate we will unlikely diagnose it but I’m quite desperate.

 

[ericmark]

For the RCD to trip, there needs to be an imbalance between the lives, that's the line out and neutral return, in the main this means some power goes to earth, so we are trying to work out why power goes to earth when the tap is turned on.

It could be a under sink heater turns on, or the water leaks onto some device, or a waste disposal unit is leaking, so we can try to shorten the list, likely your RCD feeds a number of MCB's one idea is to turn them off, then try tap, and if does not trip, turn on one at a time and see which circuit causes it to trip.

Pictures are good.

 

[pcaouolte]

Another possibility is that the water supply pipes to this tap are carrying a bit of current which is earthed through the water when it reaches the drain. Does the same thing happen if you put a plastic bucket or bowl in the sink and fill it from the tap?

 

[conny]

Is this one of those Quooker(?) style taps that heat the water instantly?
I think some posters may be under the impression it is a standard tap with some electrical device/outlet underneath.

 

[Jollymol]

Another possibility is that the water supply pipes to this tap are carrying a bit of current which is earthed through the water when it reaches the drain. Does the same thing happen if you put a plastic bucket or bowl in the sink and fill it from the tap?

This is a good shout, because I have noticed sometimes it won’t trip with the tap on a lower pressure but if I empty the washing bowl into the sink it will trip?

 

[Jollymol]

Is this one of those Quooker(?) style taps that heat the water instantly?
I think some posters may be under the impression it is a standard tap with some electrical device/outlet underneath.

It’s a standard tap as far as I’m aware?

 

[pcaouolte]

This is a good shout, because I have noticed sometimes it won’t trip with the tap on a lower pressure but if I empty the washing bowl into the sink it will trip?

So if you fill a bucket from another tap and empty it into the kitchen sink, without the water touching the kitchen tap, does the RCD trip. If so it is nothing to do with the tap and almost certainly a leak on the drain from the sink.