rcd tripping

[Beelzebub666]

Hello,
I have a dual RCD CU, one side of which tripped and wouldn't reset. I tracked the problem to the circuit which does the central heating pump etc and an immersion heater which is not normally used (fused switch is left off and gas central heating used instead) by disconnecting the neutrals in the CU with the MCBs off, then reconnecting one at a time to see which caused the RCD trip. However, the problem then disappeared before I could isolate the bits on the problem circuit. The RCD still operates with the test button, but whatever caused the trip is no longer doing so.

So, two questions -
1) suggestions as to cause and likelihood of recurrence
2) if it recurs and I can't solve it, is this a problem for an electrician, or a plumber?

Thanks

 

[EFLImpudence]

Don't know the cause and it may happen again.

However some RCDs won't reset unless you switch off all the associated MCBs first.

Others have to be pressed completely off before switching back on.

If it keeps happening you will obviously need an electrician.

 

[Beelzebub666]

Since it has to be some part of the central heating system, I'd need an electrician who can replace plumbing bits, or a plumber who can identify which part is the problem. Does such a beast exist? Otherwise I'm paying twice, and for an intermittent fault, paying through the nose.

 

[EFLImpudence]

Here sir

An electrician who can do plumbing would be much better than a plumber who can do electricing (what is the proper word?)

 

[Beelzebub666]

I guess wet is better than dead.

 

[Taylortwocities]

Here sir

An electrician who can do plumbing would be much better than a plumber who can do electricing (what is the proper word?)

Thinking?

 

[Beelzebub666]

Here sir

An electrician who can do plumbing would be much better than a plumber who can do electricing (what is the proper word?)

So you're accustomed to identifying an replacing dodgy CH bits? Would you say that's the norm for electricians? I'd presume this type of thing must come up a lot.

 

[EFLImpudence]

As you've said there's central heating systems.

Also electric showers, power showers, shower pumps, immersion heaters etc.
All of which involve a bit of plumbing. Better to do it all at once.

I just don't think a plumber would be used to tracing the sort of faults which would cause your RCD to trip. I don't think they would have the test equipment. I suppose I could be wrong.

 

[Beelzebub666]

OK, thanks for the help.

Not operating in North London by any chance are you?

 

[EFLImpudence]

Sorry, can't get home for lunch.

 

[Beelzebub666]

Oh yes, Dorset, hadn't seen that. So they have electricity in Dorset now? Amazing.

 

[bernardgreen]

I just don't think a plumber would be used to tracing the sort of faults which would cause your RCD to trip. I don't think they would have the test equipment. I suppose I could be wrong.

I think you are right based on experience of a couple of plumbers faced with electrical problems in various houses of friends and family. None of them had sensible test equipment. One even relied on a neon screw driver.