Electricity keeps tripping (1 yr old house)

Marsh_Samphire

We bought a brand new house in March 2005 and had some problems with it(understatement). Last summer the electrics kept tripping out, at first it was occasionally and the site manager tried to fob us off saying the circuit boards were "very sensitive"! But soon it was happening more and more and after a few weeks it happened all the time. We then realised it was every time the boiler came on so they changed various parts with no success until finally, after 8 weeks of no heating (lucky it was summer) and using the immersion for hot water, they found out the kitchen fitters had put a screw through the wiring to the boiler when they put the cupboard round the boiler!

All was well until a few weeks ago when the electrics started to trip again, but this time in the middle of the night/early hours of the morning so nothing is turning on to cause it. Again, it was only occasional but now it's going a couple of times a week, still in the night but sometimes in the daytime too. We have reported it and they are sending an electrician, but going on their past efforts it could take weeks to find the fault.

Does anyone know the best way of finding a fault or what should be tested to try and narrow it down? I'm worried their electrician will take a cursory look and blame our appliances or something to just fob us off again.

zincoxide

When you look at the fuse box - is it a specific item that keeps tripping or your whole supply?

If it's the whole suplly then it will be reasonably hard for you to track it down without the use of some good quality meters and timing!!

Heath_Robinson

Fridge/freezer?

Garetha

Try a plugin trip RCD device on the fridge/freezer and any other equipment plugged in and switched on when the trip occurs.
I found a faulty washing machine this way - the plug in tripped before the main trip.

Marsh_Samphire

The circuits that go off are on the right hand side of the main board and they are labelled cooker, water heater, upstairs and downstairs sockets. Each of these has an individual switch but these don't move, it's the main one for that side of the board that goes off (if that makes any sense)?

Thanks for the suggestion of a plug in RCD we will give that a go if the electrician who is coming tomorrow can't find anything.

If it is an appliance, would Portable Appliance Testing all of them find the fault? (And how much would that cost?!)

Mr_Meanie

You should be able to find out which circuit/appliance is at fault by process of elimination, but it would take a few days achieve.

lil_me

Last time this happened to me was a break in an extension cable :mad:

raymond

It sounds like what is termed a "nuisance" trip.

You will probably find that you have a 30mA RCD fitted to the consumer unit and all the circuits are connected to that. Cookers and immersion heaters can be quite "leaky" and will cause trips on a 30mA so you need consult with an electrician to have him [erhaps fit a split load unit where only the sockets are connected to the 30mA RCD and everything else through a simple switch.

Depending on the type of earthing you have (ie an earth stake or supplied earth) you may be able to have a 100mA RCD fitted, but that would be down to your electrician to decide for you.

raymond

BTW, you can do a "temporary fix" by ensuring that the double pole switches to your cooker and immersion are turned off when not in use rather than just using the switch on the appliance.

mepone9

get the electrician to test the rcd and the insulation resistance of the cables in the circuits covered by your rcd, this will rule out rcd & wiring problems though it should have been done at new, if you haven't found the problem switch off different circuits until you have narrowed it down to one then switch off different appliances until you found which one is the problem.

I assume they repaired the screwed cable last year.

Marsh_Samphire

They sent an electrician and he couldn't find anything so his boss came and they are going to change a switch on the RCD, which sounds like Raymond's solution. So hopefully this will solve the problem.

mepone9, yes they did repair the screwed cable, they bypassed it and used another wire instead (sorry, very non-technical explanation!). It was a different electrician last year to the ones that came yesterday and we explained what had happened last and they had a look and said it was fine.

Thanks so much for the advice, sounds like it could be sorted soon.