Dishwasher still tripping after leak repair

[Harry Bloomfield]

Couple of questions, can an earth leakage be caused by an appliance that is off but still plugged in? Or do they need to be in use as well? I'm just trying to make a list of al the appliances that are on when we use the dishwasher, to see if there's something else going on.

Yes, they can cause a trip when just simply plugged in. The trip could be caused when an appliance is in use, when it is not in use, it could even be an intermittent fault on the house wiring itself. These things are always difficult to find and usually need access to test equipment in the difficult ones.

You cannot prove it is the washer, you can only prove it is not any particular appliance by seeing if it trips when it is unplugged.

 

[MrBrindle]

Yes, they can cause a trip when just simply plugged in. The trip could be caused when an appliance is in use, when it is not in use, it could even be an intermittent fault on the house wiring itself. These things are always difficult to find and usually need access to test equipment in the difficult ones.

You cannot prove it is the washer, you can only prove it is not any particular appliance by seeing if it trips when it is unplugged.

Can these things be figured out without having to hack into walls etc?

 

[JohnD]

yes

 

[Harry Bloomfield]

Can these things be figured out without having to hack into walls etc?

Depending where in the installation the fault is, a possible yes, if the fault is behind an accessory (socket, switch etc.). It could though be a screw through a cable, or a nail through a cable under the floor. You will not know, until some tests have been carried out.

Did you carry out any work on the house soon before the issue began?

Have you any lights outside, which might have suffered water ingress?

 

[BlueLoo]

Depending where in the installation the fault is, a possible yes, if the fault is behind an accessory (socket, switch etc.). It could though be a screw through a cable, or a nail through a cable under the floor. You will not know, until some tests have been carried out.

Did you carry out any work on the house soon before the issue began?

Have you any lights outside, which might have suffered water ingress?

A good post. Could have been a errant nail or screw recently fitted somewhere ......

 

[MrBrindle]

Depending where in the installation the fault is, a possible yes, if the fault is behind an accessory (socket, switch etc.). It could though be a screw through a cable, or a nail through a cable under the floor. You will not know, until some tests have been carried out.

Did you carry out any work on the house soon before the issue began?

Have you any lights outside, which might have suffered water ingress?

No, no work carried out before the issue began.

Dishwasher was tripping electrics when running. Pulled dishwasher out to discover a leak behind the plasterboard approx 1ft away from the dishwasher socket. Had the pipe fixed, waited 2 weeks for the area to dry, plugged dishwasher back in, but still was tripping.

We do have an outside light, but the lights are not on the RCD ring.

Could the dishwasher have suffered any damage at all when we had the leak? There wasn't any water on the machine, just that general area was damp for a few weeks (maybe months).

Lastly, could one of the MCB's be knackered? However, none of them trip (switch down) when the RCD trips.

 

[Harry Bloomfield]

Could the dishwasher have suffered any damage at all when we had the leak? There wasn't any water on the machine, just that general area was damp for a few weeks (maybe months).

Unlikely, I would favour the fixed part of the installation - the socket, but I think you have covered that issue. Hopefully an insulation resistance test will find the cause.

 

[MrBrindle]

Unlikely, I would favour the fixed part of the installation - the socket, but I think you have covered that issue. Hopefully an insulation resistance test will find the cause.

Could the socket be problematic even though it's off??

Think I'm going to stop pestering people on here now!

 

[JohnD]

Could the socket be problematic even though it's off??

is it wet?

or scorched?

 

[MrBrindle]

is it wet?

or scorched?

Not at the moment no, and looks ok to me, Although I didn't inspect the connections inside closely.

 

[JohnD]

no reason to suspect it then

but you can easily swap it for a new one if you have doubts.

examine the wires for any signs of damage, such as being trapped or rasped by a screw or metal edge

 

[MrBrindle]

no reason to suspect it then

but you can easily swap it for a new one if you have doubts.

examine the wires for any signs of damage, such as being trapped or rasped by a screw or metal edge

When I opened that socket up I did notice that the earth cable (yellow and green right?) had 1-2mm of copper exposed - not by the connections to the socket but close to the grey outer sheath. As if it was nicked or sliced when cutting the wires. But then the socket is off in the wall now, so that shouldn't really be an issue?

Also the earth wire has multiple tight bends where they've obviously squished it into the socket wall box.

 

[Harry Bloomfield]

Could the socket be problematic even though it's off??

If the socket has been damaged, then yes - irrespective of on or off, it could be the cause. Turning the socket off, it still remains live at the back, the switch only turns off anything which is plugged into it. Is there sign of burning or arcing at the socket?

Even turning all of your sockets off at the MCB, may not prove that circuit is not at fault, if the RCD still trips with them off.

 

[MrBrindle]

If the socket has been damaged, then yes - irrespective of on or off, it could be the cause. Turning the socket off, it still remains live at the back, the switch only turns off anything which is plugged into it. Is there sign of burning or arcing at the socket?

Even turning all of your sockets off at the MCB, may not prove that circuit is not at fault, if the RCD still trips with them off.

Oh is it? And there I've been fiddling with it with it turned off on the counter top!

I can't see any burning or arcing to be honest, but like I said before, the leaking pipe went horizontally above that socket (poor design), so could have been exposed to water.

 

[Harry Bloomfield]

Oh is it? And there I've been fiddling with it with it turned off on the counter top!

OK, then if the counter top switch is a double pole, that does completely isolate the socket.