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First lightbulb fail


Adsibob

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After 25 months in the new house, we’ve had our first lightbulb fail, a GU10 6W non-dimmable. 
It was fitted in our understair loo, so no window to provide natural light. It probably gets switched on and off at least 5 times a day, some days more. Let’s say 6 in/offs on average, over 760 days (ignoring holidays when we are away). So 4560 on/offs and then it’s failed. In terms of hours on, the kids sometimes forget to turn it off, so maybe it’s running at most 4hr a day, so 3040 hours total.

 

Should I feel conned that the bulb was marketed as lasting “up to 20,000 hours” or is the multiple on/offs a day the limiting factor here?

Edited by Adsibob
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Well the old Tungsten bulbs were rated at a nominal 1,000 hours or about a year at 4 hrs / day.  How many bulbs have you got? 

 

The weakness with these is that the cheap capacitors(s) in the voltage drop-down circuit can blow.  Big Clive on Youtube did a teardown explaining the failure mode.

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I'd guess that it's in a recessed down lighter fitting. If it is they tend to get warm which seriously reduces the life expectancy of LED bulbs.

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At least you had the sense to fit light fittings where you can change the bulb.

 

There is a growing trend for downlighters to have non replaceable bulbs.  If anyone asks me to fit some (I would not buy them) I advise them to go and buy a box of spares, on the basis when one fails in a few years time, you probably won't be able to buy identical replacements.

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1 hour ago, ProDave said:

At least you had the sense to fit light fittings where you can change the bulb.

 

There is a growing trend for downlighters to have non replaceable bulbs.  If anyone asks me to fit some (I would not buy them) I advise them to go and buy a box of spares, on the basis when one fails in a few years time, you probably won't be able to buy identical replacements.

I wish someone had told my electrician this!

He fitted Saxby downlights. £10-12 each and they haven't lasted 18 months. I will systematically change them over time

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1 hour ago, ProDave said:

At least you had the sense to fit light fittings where you can change the bulb.

Slightly different but a relative has had her LED  headlight fail on her car the LED,s are built in it and just the headlight unit is over £800 (I am glad I drive an old banger with halogen bulbs 🤷‍♂️).

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33 minutes ago, joe90 said:

Slightly different but a relative has had her LED  headlight fail on her car the LED,s are built in it and just the headlight unit is over £800 (I am glad I drive an old banger with halogen bulbs 🤷‍♂️).

That is criminal, I thought things had to be "repairable" now?

 

That's one more thing on the list to check next time I buy a car.

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43 minutes ago, joe90 said:

Slightly different but a relative has had her LED  headlight fail on her car the LED,s are built in it and just the headlight unit is over £800 (I am glad I drive an old banger with halogen bulbs 🤷‍♂️).

 

And I thought my Mondeo was a pain needing a T30 torx and a Phillips to change a bulb. 

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1 hour ago, ProDave said:

That is criminal, I thought things had to be "repairable" now?

Yes I agree, but the new “repairable “ was brought in more recently than her car was made, plus I am sure the manufacturer would say replacing JUST the headlight is a repair 🤷‍♂️

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7 minutes ago, joe90 said:

Yes I agree, but the new “repairable “ was brought in more recently than her car was made, plus I am sure the manufacturer would say replacing JUST the headlight is a repair 🤷‍♂️

Then they need to supply parts at a reasonable price.  There are 2 headlights in a car (sometimes more) I simply do not believe at manufacture time they cost £1600 which would have been more than 5% of the cost of the car (possibly a lot more)

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Posted (edited)
5 hours ago, billt said:

I'd guess that it's in a recessed down lighter fitting.

No, it is in a down lighter, but the down lighter is surface mounted. There doesn’t seem to be any ventilation to the base of the down lighter. It’s basically this:

https://www.commerciallightingbyrightlights.co.uk/one-light-12105mbbs-brushed-brass-gu10-10w-dark-light.html?utm_term=&utm_source=google&utm_medium=cpc&gad_source=1&gclid=CjwKCAjwz42xBhB9EiwA48pT75xTxg5FDhWUFUgLOexHikOUfwUMHcnyLNH1MxIbpJOgs0kCf-4B-xoCMl0QAvD_BwE

 

as you can see, that is designed for up to 10w GU10 bulb, and I was only using 6w. The replacement I fitted is only 4.3w, so let’s see if that lasts any longer. 
 

Just a bit pissed of because the original light bulb was quite expensive, £10 or so. Not all of the ones I’ve fitted are that expensive, but for some fittings we used what we thought were high end bulbs with high CRi index and particular beam angles (I a this one was 25 degrees, which is what bumped up the price). 

Edited by Adsibob
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Didn't the cheap ones used to be made with glued connections  instead of solder and it melted?

They also used to have great big metal heatsinks ( or pretend ones in plastic) but don't any longer.

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I think the LED GU10's I have were Screwfix cheap ones (probably LAP) sold in boxes of 10 for about £1 per lamp.

 

Only 2 failed so far in nearly 5 years.

 

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I generally steer clear of LAP. It rhymes with a good description of its quality. GU10 lamps are meant to be quite good, and I’ve heard that from a few sources. Integrated downlights - not good. Switches and sockets are comically bad. 

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20 hours ago, Adsibob said:

Should I feel conned that the bulb was marketed as lasting “up to 20,000 hours”

A lifetime of '20,000 hours' is most likely referring to the 'catastrophic failure rate', often 10%, under which no more than 10% of the bulbs should fail within that time. But someone has to buy the ones that make up that 10% - looks like it could have been you :(

 

41 minutes ago, CalvinHobbes said:

I was going to buy spots or downlights and will now make sure the bulb can be swapped out

For a step-up from GU 10s, without going to sealed units, take a look at @Carrerahill's tip of using Tridonic LED modules. I'll be installing a batch over the next few weeks.

 

The only sealed lights that I'm installing are are in-floor uplighters by Collingwood Lighting - expensive but they've a good reputation.

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