Multiple blown GU10s

[jado84]

Hi all,

The flat I've just moved into has 8 GU10s in the kitchen/living area. When I walked in and flicked on the switch for the very first time, the breaker tripped. On turning it back on, four of the GU10s have blown.

One I'd expect given how prone cheap GU10s are to going, but four in such close proximity is making me a bit suspicious.

I'd quite like to install the fancy smart bulbs I have bought with me, but at £25/pop I don't fancy losing four in case there's an issue with the wiring or the cans.

Am I being too fussy, or should I ask the landlord to get an electrician out to check? Alternatively I could just order four cheap GU10s and see if they die before installing my precious ones.

I've included a plot in where G is a working GU10, P is the (working) pendant B22, 4 is a (working, if dim, G4) and X is a GU10 that has blown. All GU10s and G4s are on one dedicated breaker at the consumer unit ("kitchen lights"). There is a separate switch for the G4s and the GU10s. The pendant is on a different breaker (the main lights circuit).


4 4 4
G G G G
G
P X X
X X

Cheers

 

[JohnW2]

The flat I've just moved into has 8 GU10s in the kitchen/living area. When I walked in and flicked on the switch for the very first time, the breaker tripped. On turning it back on, four of the GU10s have blown. One I'd expect given how prone cheap GU10s are to going, but four in such close proximity is making me a bit suspicious.

If you've only just moved in and what you describe was the first time you'd switched on the lights, you presumably don't know when the four bulbs died. One presumably died when you switched them on (hence tripping the breaker) but isn't it possible that the other three were already died maybe having died a long time ago, gradually and one at a time over months, or even years? Prior to moving in, had you ever seen all of the lights working?

I'd quite like to install the fancy smart bulbs I have bought with me, but at £25/pop I don't fancy losing four in case there's an issue with the wiring or the cans.

Without very deeply scraping some very obscure barrels, there's not really anything about the wiring, or even fittings, that can make bulbs die. However, to reassure yourself ...

.... Alternatively I could just order four cheap GU10s and see if they die before installing my precious ones.

... would be a reasonable, and not very expensive, approach.

Kind Regards, John

 

[winston1]

If you are buying new lamps get GU10 LEDs.

 

[GarethW]

If I recall correctly, the closer you are to the sub-station the higher your voltage is.
So if a standard incandescent bulb is rated at 230 volts and your actual voltage is 253 volts (+10% / –6% tolerance), that could be why they are blowing.
As Winston suggested, get LEDs that are far more forgiving for voltage tolerances.

 

[ericmark]

The rules for landlords in England, Scotland and Wales are different, and as to who can do want, it depends on your contract, in general the lights are of three types.

Tungsten, fluorescent or LED, new rules say how many lumen per watt bulbs must be, but it is not clear if landlords need to change existing bulbs or not.

You have raised a question, with new builds the type of bulb holder had to stop one using inefficient bulbs, but with rental not a clue who buys bulbs, and how it is ensured hot bulbs are not fitted into holders designed for cold bulbs.

But as said in the main there is nothing which can make the installation blow 230 volt bulbs, it can be debated if a SPD is not fitted it could cause LED bulbs to be damaged by spikes, but I think unlikely.

 

[JohnW2]

If I recall correctly, the closer you are to the sub-station the higher your voltage is.

Indeed - inevitably so. ... but there's nothing one can do about how close one's house is to the sub-station.

So if a standard incandescent bulb is rated at 230 volts and your actual voltage is 253 volts (+10% / –6% tolerance), that could be why they are blowing.

Well, as I've said, I don't think we have any clue as to how quickly the OP's bulbs died (some could have been dead for ages when he moved in), but it's certainly true that an incandescent bulb (and probably many LEDs) are likely, on average, to die earlier with a 253V supply than a 216.2V (230V - 6%).

As Winston suggested, get LEDs that are far more forgiving for voltage tolerances.

I don't think that is a foregone conclusion, particularly for cheap LEDs - but it's good advice, since there are plenty of other reasons for moving to LEDs.

Kind Regards, John

 

[JohnW2]

..., new rules say how many lumen per watt bulbs must be ...

Which 'new rules' are you referring to?

Kind Regards, John

 

[securespark]

.

 

[JohnW2]

.

again?

Kind Regards, John

 

[ericmark]

Which 'new rules' are you referring to?

Kind Regards, John

75 lumen per watt. Now it seems in Part L building regulations, the box on my desk says 345 lumen 5.5 watt for a wi-fi GU10 bulb, so 62.7 lumen per watt for an LED Smart bulb bought in local shop (National chain) about a month ago.

So even LED bulbs today may not comply.

6.58 Where installed in a new or existing dwelling, each internal light fitting should have lamps with a
minimum luminous efficacy of 75 light source lumens per circuit-watt.

As we have seen with Part P, the "Approved Document" does not always follow the law, in my own house I would still use quartz halogen where it suited me, if I wanted the heat or used the light very little, what I am not sure about is what the rules are with rented?

Back in the 50's one would expect a tenant to provide bulbs as an when they fail, but with both fluorescent and LED we now have bulbs/tubes/fixtures which are designed with a 25,000 hours life, or more, and often not easy to change, some times requiring the whole fitting to be changed.

The flat I've just moved into has 8 GU10s in the kitchen/living area. When I walked in and flicked on the switch for the very first time, the breaker tripped. On turning it back on, four of the GU10s have blown.

8 x 50 watt = 400 watt = 1.7 amp, unlikely to trip a 6 amp type B trip.
However add to it other lights, and comments like "(working, if dim, G4)" one starts to wonder if all tungsten lighting? The problem is for some time the pearl B22d tungsten bulb has been unavailable, and one should not dim quartz bulbs, and quartz bulbs do tend to have an inrush. I have never gone mad with quartz bulbs so don't really know how many can be put on a B6 MCB, today having 16 LED GU10 bulbs on a B6 MCB is nothing, but could see there being a problem with quartz, although only 3.4 amp running the inrush on switch on would be well over that.

I know when I sold my mothers house, the electronic TRV heads were replaced with wax type, and I can see how a tenant may fit smart lights, but replace with tungsten before leaving taking the LED with him, I have a draw full of new bulbs tungsten, CFL, and LED and I am sure I could repopulate many of the lights with tungsten if I wanted to. Looking at 5 watt GU10 colour changing bulbs pack of 3 is £30 so I can see why some one would take them with them.

Looking at the "Energy Performance Certificate" for my old house it says

Lighting	Low energy lighting in 71% of fixed outlets	Very good

I do wonder where the 29% non low energy lighting was, I was unaware I had any, this house says

Lighting	Low energy lighting in 23% of fixed outlets	Poor

And yes when I moved in many of the lights were tungsten, would be interesting to see what it says for your flat, did some one put all the old bulbs back in before moving out?

Only home I have ever rented was in Hong Kong, so I have no idea as to the rules in UK, those who rent need to pass an exam I know, and studying for the exam tells the landlord what he is expected to do.

As of 1 April 2018 there is a requirement for any properties rented out in the private rented sector to have a minimum energy performance rating of E on an Energy Performance Certificate (EPC). The regulations came into force initially for new lets and renewals, but extended to existing tenancies on 1 April 2020.

So to allow tungsten lamps to be fitted would affect the rating, much depends how close the property is to being in wrong band. Also

The minimum rating is due to rise from E to C in 2025 for new tenancies and 2028 for all tenancies.

Some of the measures to get more points are silly, £4k to £6k spent will reduce costs by £48 per year by insulating our floor, so 83 years pay back time, but lighting spend £50 and gain £56 in a year it says, so Energy Saving lighting must be high on the list to get C by 2028. I bit daft really, we know main loss of heat is due to old double glazed units, but changing them with not change the EPC rating.

However I can't see how a landlord can allow a tenant to fit tungsten lamps?

 

[jado84]

If you've only just moved in and what you describe was the first time you'd switched on the lights, you presumably don't know when the four bulbs died.

Thanks for taking the time to think this through and write your post John, you're quite right. Unfortunately moving house seems to be the enemy of critical thinking!

 

[jado84]

.

If I recall correctly, the closer you are to the sub-station the higher your voltage is.
So if a standard incandescent bulb is rated at 230 volts and your actual voltage is 253 volts (+10% / –6% tolerance), that could be why they are blowing.
As Winston suggested, get LEDs that are far more forgiving for voltage tolerances.

I can actually see the doors to the substation from my window and it's no more than 30 foot as the crow flies across the courtyard. However, as it serves just this ~10 y.o. apartment block (and I have a number of rather prima donna electrical devices which haven't had tantrums yet) my hope is those installing it sized it appropriately.

My multimeter packed in recently and I'm not especially keen on buying another yet, but as my new bulbs are LED GU10s from a relatively reputable brand with any luck we should be ok.

Thanks

 

[winston1]

Tungsten, fluorescent or LED, new rules say how many lumen per watt bulbs must be, but it is not clear if landlords need to change existing bulbs or not.

Do landlords even have to supply bulbs?

 

[jado84]

Looking at the "Energy Performance Certificate" for my old house it says
I do wonder where the 29% non low energy lighting was, I was unaware I had any, this house says And yes when I moved in many of the lights were tungsten, would be interesting to see what it says for your flat, did some one put all the old bulbs back in before moving out?

Thanks, yeah I do wonder if that's the case actually. Also the old tenant didn't really look after the place so I'd suspect if he changed the bulbs himself at the end of the tenancy he may smeared grease on cheap bulbs; I don't know about domestic electrics (hence I'm here!) but from my live events production experience, touching bulbs that will later get hot without wearing gloves is a huge no-no because of the risk posed by grease.

 

[jado84]

Do landlords even have to supply bulbs?

My understanding (based on years of renting, rather than a knowledge of regs) is that they don't. It would be acceptable for landlords to leave the cans empty, and for the tenant to do the same at end of tenancy. Conversely, if working bulbs are supplied then working bulbs should be left. Happy to be corrected if I'm wrong though.

On a practical note, I imagine doing most of the inventory/cleaning/maintenance that occurs between tenancies would be nigh on impossible without lighting.

I'd also suggest many landlords would prefer ensuring bulbs are present and working to avoid calls from their tenants about this, given how cheap non-smart LED bulbs are now.