Earth issue on lights found 6 months after rewire

[Gemmadoll]

Hi all

We have a 1930s house, we replaced the kitchen in June and found the kitchen/cooker were on the same circuit as the rest of the house.  This prompted us to get a rewire of the kitchen and our electrical box was also replaced with an up to date metal box.

All seemed fine and we were given a cert but we got a call in December saying an auditor realised they hadn’t checked the entire house so could they come back and do it.  We were fine with this so before Christmas they came and tested and found there was a break in our earth on the lighting circuit.

now they want to come and fix this which will potentially involve taking up our floor in our loft room to access upstairs ceiling lights and checking all of our wall lights downstairs.  I guess once they find the issue this will involve chasing out etc.

We have a functioning RCD which does work, we have metal light switches through the entire house - no plastic.

What will potentially happen with no earth - the RCD will shut off the circuit but I know the RCD should be secondary to a functioning earth.  

any advice much appreciated!

 

[Andy™]

joints are probably all accessible...  just need to find the one with the loose connection. unlikely to need cables replaced etc. bit of testing and you could probably narrow it down to a few points without really taking much down if the fittings are class 1

no earth... potentially a fatal electric shock. RCD should trip before it can kill you, but it might not

 

[Phoenix]

It does need doing, and as Andy says, there is a good chance that it won't be much in the way of disruption (but there is a bit of change it could be ***** of a fault to find in a hidden joint box etc).

They should have tested and sorted the certification straight after doing the work, I think I'd be wanting an explanation of why it has taken until now to do the testing.

I suggest you permit them back to start tracing the fault, but state that you want to be notified before do anything like pulling back carpets or damaging wall services. Expect them to be able to tell between which points the fault lies before letting them do this e.g. "We think there is a loose connection in a joint box above the lounge light because there is only one cable at the light and only one at the switch. and the lounge is the first one without an earth". rather than "I've checked everything else, I'm going to have a look under all the floors for joint boxes to check"

With metal switches, a continuity test can be done from any convient earth, so you can say, Yes, "still got it there", "no lost it by the time it gets to that one", it gives you a good idea where it is likely to be without even having to go up and down a step ladder. Provided the connection with the problem is accessible, then with sensible techniques these issues can usually be located quite quickly

 

[ProDave]

It's hard to generalise. It depends when it was last rewired.  There is a chance it's all wired spider fashion to a big lighting junction box somewhere, usually one per floor so one in the loft and one in the inter floor void.  If it is wired like that the problem become WHERE is that junction box?  It can take some time to find it. It is quite common to find broken earths at such a junction box.

As others say, until they have a look and start testing you don't know what is wrong, it could be simple it might not be.

 

[NozSpark]

I've had a few faults (to find) like this..... It usually ends up being an earth wire that hasn't been terminated correctly, or has been cut back at a light fitting.... it could only take the one fault to have an effect on the vast majority of the circuit

From your point of view though, this should have been picked up when they did the job and sorted out at that time

 

[Sidney]

Have you changed any light fittings in the property at any point in time? If so it might be worth turning of the circuit at the consumer unit and checking the connections at any lights you have replaced.

 

[Gemmadoll]

Thanks all for the advice so far It’s really helpful.  Yes we have replaced numerous lights since we moved in so it’s worth us checking those.

we weren’t sure where the fault lies as they didn’t rewire the whole house but I believe as they changed the box they should have tested everything before they walked away - is that correct?  

 

[Murdoch]

Thanks all for the advice so far It’s really helpful.  Yes we have replaced numerous lights since we moved in so it’s worth us checking those.

we weren’t sure where the fault lies as they didn’t rewire the whole house but I believe as they changed the box they should have tested everything before they walked away - is that correct?  

The fact they came back is encouraging but any faults identified, would normally be extra cost to locate and fix.

as a diyer, it’s unlikely you would have the necessary test equipment to check and then confirm the issues fixed 

 

[kerching]

You say an Auditor picked up the fault?.......just curious who this was and why?.....or was it just part of the installing contractors annual assessment ?

 

[NozSpark]

You say an Auditor picked up the fault?.......just curious who this was and why?.....or was it just part of the installing contractors annual assessment ?

Possibly part of their work generation process??? or maybe they recently got rid of a dodgy employee and are going around checking up on their work

 

[Phoenix]

I did wonder if they have fallen into the hole that some bigger firms do when doing small works, In that the guys installing don't do testing, they have a separate guy who goes around doing the testing, this works ok-ish on bigger projects, which are measured in months, if their small works teams opperate in the same way, what you often get is the testing bloke rushing around left right and centre, trying to keep up with jobs, and the big contracts take precidence when hndover starts looming, and before you know it, you have got a hell of a backlog on the small works. Its a less than ideal way to operate, but can be quite difficult to break out of when the installation guys are very rusty on testing, and often do not want to be less rusty as they don't like testing. They then get booked on Cg2391 and end up struggling and the failing it due to not having the basic testing knowledge assumed by the course

 

[Andy™]

I did wonder if they have fallen into the hole that some bigger firms do when doing small works, In that the guys installing don't do testing, they have a separate guy who goes around doing the testing, this works ok-ish on bigger projects, which are measured in months, if their small works teams opperate in the same way, what you often get is the testing bloke rushing around left right and centre, trying to keep up with jobs, and the big contracts take precidence when hndover starts looming, and before you know it, you have got a hell of a backlog on the small works. Its a less than ideal way to operate, but can be quite difficult to break out of when the installation guys are very rusty on testing, and often do not want to be less rusty as they don't like testing. They then get booked on Cg2391 and end up struggling and the failing it due to not having the basic testing knowledge assumed by the course

some larger jobs do have different people doing the I&T from the installation, but for small jobs like this, if you cant I&T your own work then you shouldnt be doing any installation work. also the installation should not have been energised until the I&T had been completed even if that was by someone else

 

[Evans Electric]

Yes we have replaced numerous lights since we moved in so it’s worth us checking those.

I'd say definitely do those before anything else  , the install may have been fine until lights were changed .  

A classic DIY trick is to push the green /yell sleeving  into a terminal but leaving the copper core behind  , unconnected . 

 

[Phoenix]

some larger jobs do have different people doing the I&T from the installation, but for small jobs like this, if you cant I&T your own work then you shouldnt be doing any installation work. also the installation should not have been energised until the I&T had been completed even if that was by someone else

I agree entirely, but seen things like this happen. You'd be supprised, there are many out there on big sites who would struggle to adequately test a small board change job, simply because they have never needed to test in the real world, someone else has always done it for them.

Its not right, but its what can happen with a workforce thats more familar with big jobs

 

[kerching]

A classic DIY trick is to push the green /yell sleeving  into a terminal but leaving the copper core behind  , unconnected . 

Yep

thats why I always use smallest green sleeve possible....usuall 2mm as it fits everything up to and including 6mm T&E.  also takes a lot less space...always remember to finish off with a quick tug though

 

[Evans Electric]

I always use smallest green sleeve possible....usuall 2mm as it fits everything up to and including 6mm T&E.

Me too  ,  don't like to see really wide sleeving on small cores ,  2mm is king. 

 

[kerching]

Me too  ,  don't like to see really wide sleeving on small cores ,  2mm is king. 

Probably just me ( usually is ) but it seems to last a lot longer on a drum than loose!.......I always throw a load of short bits about 6" long (along with bits of blue and brown) into. bottom of tool box.     Throw one long piece in, lose it and you've lost it all: lose one short bit?....not an issue

 

[Andy™]

Yep

thats why I always use smallest green sleeve possible....usuall 2mm as it fits everything up to and including 6mm T&E.  also takes a lot less space...always remember to finish off with a quick tug though

hate those who use 4mm+ sleeving. they are usually the muppets who also twist the earths together and fit into one bit of sleeving

 

[Evans Electric]

they are usually the muppets who also twist the earths together and fit into one bit of sleeving

They are the children of Bealzebub  , they should be struck down !!!!         

Bit OTT there .....perhaps they should be led into the way of the 2mm sleeving . 

 

[kerching]

muppets who also twist the earths together and fit into one bit of sleeving

A twister is NOT a Tester......end of!