RCD FUSEBOX

[fuzzy]

I've just had a bathroom refit. electric shower was taken out and the cable wired into a dead end junction box and left under the floor. the seperate fuse switch for this has also been switched off.
the switch for the extractor fan has also been wired into a dead end box.
I now have a shower running from the combi boiler and no new electircs in the bathroom.
prior to this I have had not problems, but since then I have had periodic fusing on the ring main, so far 3 times in the last 4 weeks(lights still work).
the fuse box will not turn on straight away. after about 10mins it lets me switch back on.
nothing seems to prompt it to happen, I can boil kettles turn on toasters and run as many appliances as I like and I cannot make it happen. it just does for no apparent reason
there is not specific time or pattern to it.
does anyone have any ideas? do RCD fuse boxes wear out? could it be that?
could an electician trace a fault like this easily?

 

[RF Lighting]

does anyone have any ideas? do RCD fuse boxes wear out? could it be that?

It is unlikely that the RCD will have gone faulty

could an electician trace a fault like this easily?

If you are lucky, then yes, but intermittent faults are the very worst faults to try and track down.

Is it possible that a cable has been damaged / nailed through while the refit was being carried out?

 

[fuzzy]

I don't think a wire could have been damaged. the wires underneath the floor are all clustered to one side of the bathroom under the bath (we just replaced like for like sadly). although having said that I think the earth wire may be near the new sink. if they have clipped the earth wire, could this do it?

 

[RF Lighting]

It is unlikely that an earth wire would cause this problem.

Can you isolate one circuit at a time to try and work out which is at fault. This would be a massive time saver for the sparky trying to find the fault (and a money saver for you too )

 

[fuzzy]

when it tripped this morning, I ran through the switches on the fuse box, and put them back one at a time. the one labeled kitchen made it trip the first time ( but this was within that 10 min period that I normally have to wait), but when I did it again , turning them on one at a time, it just came back on and has stayed there all day.
if it is connected to the kitchen ciruit thats all a bit odd isn't it.
do you think I could just have a problem downstairs in the kitchen somehow and this has come out at the same time by coincidence???

thanks for your help so far by the way.

 

[hacman mk2]

Could it be the new boiler is on the rcd side. (spurred off the ring)

Rcds tend not to like central heating systems much.

If it is on the rcd side I would have it moved to the non rcd side. Pref on its own circuit.

 

[fuzzy]

thanks hacman, but the boiler hasn't moved.
we replaced this last year, and had no problems until now

 

[RF Lighting]

Try keeping a log of times, what you are doing / using etc to see if any pattern emerges. How long ago was the bathroom fitted? and did the problems start straight after this? Also the problem may be in the kitchen and the bathroom may be a red herring, but the bathroom would be the starting point for me at the moment. Sometimes a fridge motor or similar starting up may cause an RCD to trip.

 

[fuzzy]

cheers RF
the problems started straight after the bathroom refit.
I'll try keeping a log, but have sort of done this in my mind already and nothing seems to tie in with it tripping.
If the wiring has become sensive to a fridge motor etc, is there anything I can do to stop it happening.
I'm OK with it tripping if I am here but if I'm away on hols it kinda causes a problem.......

 

[plugwash]

are you sure the shower cable was terminated in a suitable junction box and not just bodged with insulation tape or similar?

 

[fuzzy]

plugwash.

no is the honest answer. I paid a guy to fit the bathroom, and I'm not 100% sure what floor board he put it under.
but.. if the fuse labeled "shower supply " is turned off at the fuse box, surely this would not matter ? (sorry if this sound dumb but as you can tell I'm not a spark)
if this is a possibility , then can someone shout, and I'll get the saw out and get the floor boards up to check the box (or taped up bundle of wires!!!).

 

[plugwash]

sometimes a neutral to earth fault can cause RCD trips.

try completely disconnecting the shower cable from the consumer unit. Also inspect the termination of or completely disconnect the fan cable.

 

[fuzzy]

cheers plugwash

I've already disconnected the fan, at least I think so, but I'll check.
I'll do the shower supply at the fuse box tomorow.