RCD keeps tripping.

[B Huey]

Our RCD keeps tripping and I'm getting nowhere trying to solve the problem, any advice will be appreciated.

So far I've used a circuit tester on all sockets in the house, this showed no faults.

The odd thing is that it usually trips overnight while we're in bed.

The RCD has a push button on it, if pressed it trips, is this normal?

Any ideas?

[Pete102]

The button is a test button its supposed to trip. Do u have any equipment set up to come on only at night? Immersion heater? Central heating? Etc...

[thinfourth2]

Is it the main RCD or is it one on a circuit?



Assuming its the main one then if it is happening at night then switch off all your circuit breakers and then switch on one or two.

Go to bed and sleep

If you wake up and the rcd is still on then the fault is not on the circuits you left on.

Keep repeating this experiment until you narrow it down to one circuit.

Now you are down to one circuit if it is a ring main then unplug everything and see if it still trips.

if yes then there is a wiring fault if no its something that is plugged in

[B Huey]

Pete102 said:

The button is a test button its supposed to trip. Do u have any equipment set up to come on only at night? Immersion heater? Central heating? Etc...

Only the combi boiler but the heating has been off lately.

[B Huey]

thinfourth2 said:

Is it the main RCD or is it one on a circuit?



Assuming its the main one then if it is happening at night then switch off all your circuit breakers and then switch on one or two.

Go to bed and sleep

If you wake up and the rcd is still on then the fault is not on the circuits you left on.

Keep repeating this experiment until you narrow it down to one circuit.

Now you are down to one circuit if it is a ring main then unplug everything and see if it still trips.

if yes then there is a wiring fault if no its something that is plugged in

It's the main RCD, trips everything bar the lights.

Thanks for the advice.

[bimsb6]

If it's the main rcd how are the lights still on ?

[VEX]

Our cooker used to do that, but only when it reached 200 degrees.

New heater eliment and fault stopped, to ages to find though.

V.

[Dogwatch]

bimsb6 said:

If it's the main rcd how are the lights still on ?

Sounds as if it must be something plugged into/connected to the ring main. Whatever it is can't be functioning so must get noticed eventually?

[Ganglandboss]

thinfourth2 said:

Is it the main RCD or is it one on a circuit?



Assuming its the main one then if it is happening at night then switch off all your circuit breakers and then switch on one or two.

Go to bed and sleep

If you wake up and the rcd is still on then the fault is not on the circuits you left on.

Keep repeating this experiment until you narrow it down to one circuit.

Now you are down to one circuit if it is a ring main then unplug everything and see if it still trips.

if yes then there is a wiring fault if no its something that is plugged in

If the fault is between a neutral and earth, switching off a breaker will not prevent the RCD tripping. I would recommend unplugging everything and seeing if it still trips. If not, then try operating appliances one by one. The fridge is often the culprit as it is a class 1 appliance (earthed) with a motor that operates intermittently throughout the night.

If the RCD still trips with nothing plugged in and fixed appliances disconnected, it is a wiring fault. If that is the case, kill the power and have a look behind sockets for obvious damage to cables. If you have no joy, you will need to get a spark in who will have the necessary test instruments to trace the fault.

[fatboy b]

Maybe a rodent or two chewing the wires somewhere in the loft?

[Globs]

Usually one of two things IME:

1) Insects building stuff that blocks drain-holes in outside lamps
2) Immersion heater top filling with water from slow leak around seal being trapped by insulation.

I think you need to start unplugging things to isolate house vs add-ons.

[smifffymoto]

I think you have a loose neutral somewhere.
Identify which circuit is faulty and then check all the neutrals are tight.

[Ganglandboss]

smifffymoto said:

I think you have a loose neutral somewhere.
Identify which circuit is faulty and then check all the neutrals are tight.

How have you worked that out?

[turbospud]

B Huey said:

Our RCD keeps tripping and I'm getting nowhere trying to solve the problem, any advice will be appreciated.

So far I've used a circuit tester on all sockets in the house, this showed no faults.

The odd thing is that it usually trips overnight while we're in bed.

The RCD has a push button on it, if pressed it trips, is this normal?

Any ideas?

closest one to this ive been to is every 4days the rcd would trip,insulation ok,had to put in individual rcds to identify which circuit,it was the american style fridge defrost circuit switching in.
leakages that trip rcds intermitantly can be very hard to find,can be more than one,two 15ma can do it and as said its not always between l and e,switching off as much as possible will narrow the options down unless its on the house wiring

[smifffymoto]

Ganglandboss said:

smifffymoto said:

I think you have a loose neutral somewhere.
Identify which circuit is faulty and then check all the neutrals are tight.

How have you worked that out?

When I was on the tools,the majority of RCD faults were caused by loose neutrals,unless the RCD was over sensitive(highley unlikeley but not unheard of)

[pikeyboy]

we had a problem like this and it turned out to by an old brittle earth wire in an oven near the heater element. Took ages to find and five minutes to fix.