Electric costs

sand_hun

Hi folks, I recently hired an electric company to change a fuseboard/consumer unit in my house. 

Ever since they completed the work, my lights have been tripping once or twice per day. It seems to occur when I press the light switch in the kitchen and oddly, it only seems to trip after 9pm. Having communicated it to them, they said it's likely that it was an existing fault and I'm only noticing it tripping now because they installed modern technology in the form of the new consumer unit. I suspect they are probably right about this.

The kitchen has 8 spotlights and they said to identify the fault and install new spotlights with new fittings/surrounds it will cost £520 (£400 on labour costs). Does this sound reasonable?

Spinybif

Can you not identify faulty spotlight yourself ? If lighting trips regularly take out 1 bulb. If still trips put back and take out next one. If doesn't trip within a week you have found faulty unit / bulb. Put in new bulb. If still trips the spotlight fitting itself is faulty - these are simple fittings and commonly the only thing to go wrong is a loose wire which you can either refit yourself or pay a handyman to sort out in 5 minutes saving you a fortune.

sand_hun

Interesting. It's certainly given me something to think about. I should add that these ceiling fittings are quite old - probably been there over a decade. 

When the electricians were here the other day they pulled the first one out and it caused some bits of plaster to come loose, so if I were to attempt myself I'd have to be wary of that. 

They suspected it's an issue between live and neutral. 

So based on this image, would you say it's quite easy to change these bulbs/fittings even without any electrical knowledge?

ThisIsWeird

Interesting - these look like LED lamps in there.

Can you remove just the 'bulbs'? Often a rubber sucker is used - plonk it on the lens, and that allows you to give it an anti-clock part-turn, and pull. Check the voltage of the removed lamp - if it's 12V (or 24V), then there's a transformer up there in the ceiling void, and that's where I'd look for the dodgy part. If they are 240V, then they are driven direct from the mains, so could be a dodgy LED lamp, or holder.

I'd try what Spiny suggests first - remove one bulb at a time, and check for tripping.

Are these easy to replace? Yessish. As you've noticed, when you pull them out, the side springs will plough through the plasterboard a bit, so try pulling one side down a half-inch or so first, until you can see the spring (two parallel bits of wire), and then try and push that spring inwards towards the light fitting to take the tension off the p'board edge. Repeat on the opposite side, and then you can usually use your fingertips to press both sides in simultaneously and withdraw the fitting.

POWER OFF AT THE CU!

Direct replacements are easily available, as are wider decorative collars that'll hide that damage. Or, a smear of filler, sand down and paint.

One step at a time - try and remove each bulb first, and test.

sand_hun

ThisIsWeird said:

POWER OFF AT THE CU!

OK, I will try and remove the first bulb. When you say power off at the CU, do you mean I should turn off at the MAIN switch so that all power within the house is off. Or are you suggesting I turn off the individual fuse that relates to the lighting in my house? Thanks

BarelySentientAI

sand_hun said:

ThisIsWeird said:

POWER OFF AT THE CU!

OK, I will try and remove the first bulb. When you say power off at the CU, do you mean I should turn off at the MAIN switch so that all power within the house is off. Or are you suggesting I turn off the individual fuse that relates to the lighting in my house? Thanks

Lighting fuse should be fine - but make sure the lights actually go off when you switch it.

Main switch is safest of course.

Albermarle

Is the switch a dimmer switch or just on/off?

I think dimmer switches do not last forever, and can also cause issues.

Veteransaver

Is there any condensation (Eg after cooking evening meal) getting up above the lights?
These sort of nuisance trips can be difficult to pin down, the fault might not even be in the kitchen light circuit.

If it isn't happening every time you switch the lights on then it's probably not a wiring fault as such.
Is anything else in the house in particular only running after 9pm?

What sort of consumer unit do you have, is it a dual RCD one or an RCBo one?

NibblyPig

When they replaced the unit they must, as per building regulations, have done an extensive test, and provided you with an electrical installation certificate / minor electrical works installation certificate.

Amongst the paperwork they should have performed quite a few tests, and those tests should have found issues like the one you're experiencing.

If they haven't produced this then they are in violation of whatever body they belong to (assuming they're a legit company you will be able to find this on the Competent Person's Scheme) and that scheme will have measures of recourse, but you should always contact them first.

Risteard

NibblyPig said:

When they replaced the unit they must, as per building regulations, have done an extensive test, and provided you with an electrical installation certificate / minor electrical works installation certificate.

Amongst the paperwork they should have performed quite a few tests, and those tests should have found issues like the one you're experiencing.

If they haven't produced this then they are in violation of whatever body they belong to (assuming they're a legit company you will be able to find this on the Competent Person's Scheme) and that scheme will have measures of recourse, but you should always contact them first.

Initial verification is in the Wiring Regulations - it has nothing to do with Building Regulations. It is incorrect to state that testing is guaranteed to find all issues. Firstly inspection is the primary part of the process, and is merely supplemented by testing. Most issues are identified by inspection. However many faults on an existing installation could be hidden, and even testing may not show them up depending on the circumstances. It is not a magic process.

Furthermore if they simply replaced the distribution board then the extent of their inspection and testing need only be sufficient to demonstrate that the alteration to the electrical installation did not impair the safety of the existing electrical installation, and that the existing electrical installation did not impair the safety of the alteration. They are not re-verifying the existing electrical installation. That is a misconception and completely incorrect.

sand_hun

Veteransaver said:

Is there any condensation (Eg after cooking evening meal) getting up above the lights?
These sort of nuisance trips can be difficult to pin down, the fault might not even be in the kitchen light circuit.

If it isn't happening every time you switch the lights on then it's probably not a wiring fault as such.
Is anything else in the house in particular only running after 9pm?

What sort of consumer unit do you have, is it a dual RCD one or an RCBo one?

Yes, there is condensation when we do the cooking so that could be a factor. Our extractor fan is useless.

Previously it happened just once per day in the evening, however since the electricians most recent visit to inspect what I reported, it now happens EVERY time. i.e., as soon as I switch kitchen lights on it trips the fuse.

I don't know what type of CU it is.