Recent content by momo32

A more expensive though similar method is to use skirtings with channels routed in them - I think Homebase do them. They look good and claim to allow plenty of space for (low voltage/signal only!) cables. edited for spelling.

Hmm. He's got 3 cables; he's accounted for the 3 earths, accounted for 3 black wires - all connected together - ? neutrals? But so far only discussed 2 reds. Where is the third red wiring going?

Depends on length: as far as we can tell from your description your load is not more than 4kw. This gives us about 30 metres of 4 core 2.5mm SWA. Though why 4 core? If you are replacing the cable, 3 core 2.5mm would be the answer, assuming the run is less than 30m. Otherwise 4mm. edit...

Don't get that... Do you not use a DP isolator for just that purpose - isolation? I agree the CPC is always connected but the phase and neutral aren't if the DP switch is off so how can 'it feed back' anywhere??

But: he's turned off the CU in the garage (we assume DP switch?). The house RCD only trips when he turns ON the garage MCB in the house. The fault has to be (a) between phase and earth and (b) between the MCB and the supply side of the garage CU. That leaves the cable, surely? or am I being...

Just reread your first post (always wise!) and note that you had the area (over?) the cable paved. Sounds like you need to have the cable tested :( Have had similar experience recently.

So is it at all possible that it's actually the shower at fault??

Just to clarify: it is the RCD in the house CU tripping? Not the MCB beside it in your picture labelled 'garage'? Sorry, I see that's been asked earlier :-)