Electrician help - 1 recessed ceiling light keeps blowing bulbs, others OK

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georgegassaway

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There is a recessed ceiling light that has been out for some time. A month ago, I replaced the old 100 W bulb with a CFL 150W equivalent (equivalent light output to a 150 W incandescent). The next day, I noticed it was out. I removed it, tested in a lamp, and it was dead.

So, a couple of days ago, I finally replaced it with another 150 W equivalent CFL. Next day, noticed it was dead. Yesterday, I replaced it with a 100 watt equivalent CFL. And an hour or two later, I heard a single not-loud pop sound, and saw that the new 100 W CFL was out.

EmXlT4g.jpg


I will note that there are multiple recessed ceiling fixtures exactly like this one in the workshop (for screw-in bulbs), and they do NOT have any problems. Also, they are turned on by a simple on-off which, not a dimmer. And in fact, some are holding 300 W CFL's which have been fine for years, while this particular socket had never had anything bigger than 100W until last month.

So, if anyone reading this has experience as an electrician or otherwise may know…. What the heck could be causing this?

For now I’m just going to that it like it is a bad recessed lighting fixture, for whatever reason, and won’t replace bulbs in it (I considered putting an incandescent 60-75W to mostly see if it lasts or dies early too).

But I am curious to know what it might be that would causes it to blow bulbs. In the past the only issue I had with a bad fixture, like a lamp, is loss of contact so the bulb just would not come on, period. Never had anything that caused bulbs to blow.

And yes I do wonder in case it was a bad fixture, to at least then know that the only fix would be to replace it. The ceiling is higher (10 feet I think) than I’d be comfortable using a stepladder to access and remove the fixture. As it is I used a stepladder to change the bulbs and that was a scary one-hand-on-bulb and one-hand-on-ladder-top-handle situation (Yes, I have a bulb changing pole but it did not work well with the 150 W CFL).

- George Gassaway
 
I am not an electrician but I stay at a ..... nevermind.

Consumer CFL's have very crappy ballasts (cheap as possible). Heat is a big enemy of those circuits. Operating the CFL base-up makes it even worse.

Assuming you have the same CFL in other fixtures in your ceiling with no problems, if you have one of those non-contact infrared thermometers or some other way to check the temperature near the base of the bulb while operating and compare to your other cans, that would help confirm that the fixture is somehow different than the others (assuming there is now other heat source near that can.)
 
I am not an electrician, but I spend much of my life figuring out and solving weird problems.

I had a similar situation twice. Bulbs kept blowing in apparently intact fixtures, on circuits with other bulbs not experiencing problems.

First time, I wound up rewiring things. And the bulbs kept blowing. Eventually, I figured out that the fixture was poorly made such that the screwed-in bulb JUST BARELY made contact with the tongue-shaped contact at the bottom where the bulb screwed in. It was causing intermittent contact, resulting in poor bulb life. I replaced the fixture; problem solved.

Fifteen years later, I had forgotten all about that first incident. In a different house in a different state, bulbs on one side of my garage door opener kept blowing. Just one of the two bulbs, on the same circuit. Eventually I found the base of the fixture was getting so hot it was starting to melt. Turns out... wait for it... the tongue contact at the base of fixture was recessed too far, bulbs barely making contact, causing arcing and poor bulb life plus lots of extra heat. Bent tongue contact "up" a bit so the bulb could mate better with it. Problem solved. I eventually replaced the bulb-holding fixture ($5 on Amazon!) because I was worried about the partially melted bit eventually causing problems, but it lasted fine until I got around to it.

CFLs would be particularly prone to intermittent contact problems due to the circuitry involved.

Good luck!

Marc
 
Again, not an electrician but I had a similar problem with and outdoor fixture a while back and the socket was shorting to the fixture.
 
Is the CFL you are installing made to work with a dimmer switch? If it is a non-dimmable CFL, it can overheat and burn out.
 
Check it with a DMM. If you had a fan /light combo and took it out and wired in a light can you could have 2 hot wires going to it or wired backwords hot ( black wire) should be center contact
 
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Everyone, thanks for the comments, suggestions.

First time, I wound up rewiring things. And the bulbs kept blowing. Eventually, I figured out that the fixture was poorly made such that the screwed-in bulb JUST BARELY made contact with the tongue-shaped contact at the bottom where the bulb screwed in. It was causing intermittent contact, resulting in poor bulb life. I replaced the fixture; problem solved.

That MIGHT be what is happening, poor contact with that particular fixture. But it is so scary to even replace a bulb, that I can't stand up high enough, safely, to even try to pry the contact, sure can't replace the fixture (not unless I literally made up a scaffold system to stand on).

One possible workaround could be to get a bulb extender socket. And solder into its base a bit deeper contact so that the extender would get a much better mechanical contact, therefore not arc if arcing from poor contact is the issue. The price is right, at no worse physical risk than changing a bulb. So, I may try that out (with a cheaper CFL at first to see if it lives long). Plan to go to the hardware store tomorrow anyway.

mediumporcelainextender.jpg
 
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George- if it's an IC (insulation contact) fixture then perhaps the IC circuitry is acting up. It's meant to shut off the bulb if the fixture gets too hot.
 
George- if it's an IC (insulation contact) fixture then perhaps the IC circuitry is acting up. It's meant to shut off the bulb if the fixture gets too hot.
Whatever is happening, the bulbs are getting killed. Dead. I try them in a lamp after removing a good bulb from the lamp, and nothing. Even when long cooled. I still have that sad "new" 150 W CFL that only lived few hours (heck it could have gone out after 1-2 hours, but I did not notice it till the next day). Like Generalissimo Francisco Franco, it is still dead...

If I do remember to get the extender at the hardware store with the other stuff (Made a list), I'll try that (after soldering in about a 1/4" spacer to the extender middle contact) and report on the result. If the bulb lives even a few hours that would be a good sign that it was a poor contact/arcing situation. If the bulb dies early anyway, then I'm just going to give up on it, not worth risking a very bad fall/life or hiring an electrician to replace the unit.

- George Gassaway
 
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My best advice, bite the bullet and call a licensed electrician. Better than a fall or a fire. :2:
 
my bro-in-law installed a ceiling fan once,
it spun about 200mph....then smoked

tapped into 220v line :}

john
 
Whatever is happening, the bulbs are getting killed. Dead. I try them in a lamp after removing a good bulb from the lamp, and nothing. Even when long cooled. I still have that sad "new" 150 W CFL that only lived few hours (heck it could have gone out after 1-2 hours, but I did not notice it till the next day). Like Generalissimo Francisco Franco, it is still dead...
I recall reading a PDF years ago about the fallacy of economy when using CFLs in certain situations. Recessed lighting with no ventilation was one of them. The ballast overheats and fails.

Just found confirmation here:

https://www.popularmechanics.com/home/how-to/a3854/4299370/

"The typical CFL will work in most of the same fixtures and orientations as an incandescent, though one notable exception is in the overhead, recessed cans often found in foyers. Trapped heat in a recessed lighting fixture can fry a CFL unless it is specifically designed for such a placement."
 
From this Home Depot CFL selection page:

https://www.homedepot.com/c/how_to_choose_right_compact_fluorescent_light_bulb_HT_BG_EL

Indoor Reflector Bulb – A bulb that provides directional light. Indoor reflectors are used in recessed lighting, track lighting, and some ceiling fans.

it looks like this type of CFL and its ballast are specifically designed for the heat buildup in recessed lighting:

https://www.homedepot.com/p/EcoSmar...R30-CFL-Light-Bulb-6-Pack-ESBR30146/205487743

Confirmation:

https://www.webstaurantstore.com/guide/544/compact-fluorescent-light-cfl-f-a-q-s.html

Can Compact Fluorescent Lights (CFLs) be used in recessed cans, outdoor lights, or track lighting?


Yes! Always read the packaging of the CFL to be sure of its proper application, but there are a wide variety of ENERGY STAR qualified CFLs that are designed for use in most fixtures in your home or business. Product types include:

Reflectors are intended for non-dimmable track lighting and recessed cans, and some weather protected outdoor spot lights
 
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For those who skimmed over and missed it, there are a number of the exact same recessed fixtures in the room, on the same circuit (classic on/off switch, not a dimmer, not a fan), using CFL's. Some as big as 300 W equivalent.

All the rest of those are fine.

It is this ONE that is having a unique problem.

From some of the posts, it seems most likely it is poor contact in this one (IIRC, every time I replaced a bulb in that socket and screwed it in while the other lights were on, once the bulb lit up, I was not able to rotate it much farther).

So as I said, I'll try a bulb extender (about to leave to go shopping), modified for deeper contact, and see if that solves it or not.

I switched to CFL's from incandescents about 7 years ago and never looked back. Lower bills and the bulbs last way way longer (there was a "security light" I left on all the time in a room, which lasted 2 to 2.5 years, incredible) . Except for this one fixture, where clearly it ain't the bulb, it's the fixture..
 
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I think it's fair to say that each advance in technology brings with it a new set of problems to be overcome. I know that older recessed can ceiling fixtures have been problematic because they act as a heat trap which can shorten lamp life and cause fires on occasion. Older recessed cans often do not have a thermal break...newer ones do and are mandated by building codes. The last time I had additional insulation blown into my attic, sleeves were placed around every recessed can to prevent the insulation from trapping heat in the can. While this does prolong lamp life it also forms a point of heat transfer at each fixture. If I had my life to live over there would not be any recessed fixtures in my house except for my shower.

I think LED's are the wave of the future and that eventually the price will come down as more people buy them. The only thing "green" about any of this is the color of the money certain people are making by capitalizing on this current fad.
 
If its poor contact you should be able to "hear" that or see some flickering. Winston found the references for the most common problem which is heat destroying the ballasts which was the suggestion in post 4. A marginally poor connection through with a high resistance will generate more heat at the base, hotter ballast less efficient, generating more heat snowball to failure.

Your extender might just do the trick by two effects, better contact and moving the base out allowing more ventilation to run cooler. Good luck.

PS. My CFLs in kitchen recessed fixtures never got the bulb life promised by this technology, about 2-3 years then they burn out.. I replaced them with LED's.
I have never replaced a CFL in a lamp or other upright application. I have some that I moved, over 10yrs and still going strong.

For those who skimmed over and missed it, there are a number of the exact same recessed fixtures in the room, on the same circuit (classic on/off switch, not a dimmer, not a fan), using CFL's. Some as big as 300 W equivalent.

All the rest of those are fine.

It is this ONE that is having a unique problem.

From some of the posts, it seems most likely it is poor contact in this one (IIRC, every time I replaced a bulb in that socket and screwed it in while the other lights were on, once the bulb lit up, I was not able to rotate it much farther).

So as I said, I'll try a bulb extender (about to leave to go shopping), modified for deeper contact, and see if that solves it or not.

I switched to CFL's from incandescents about 7 years ago and never looked back. Lower bills and the bulbs last way way longer (there was a "security light" I left on all the time in a room, which lasted 2 to 2.5 years, incredible) . Except for this one fixture, where clearly it ain't the bulb, it's the fixture..
 
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Bad inside or external wire or connection ...is it the end of the circuit run?
Net result of fried bulbs is due to under-voltage at the bulb.
This is my guess.

The last bulb on my outdoor light circuit eats bulbs too -- low voltage means higher current which means more heat because heat is a function of current, not voltage.
Much less of a problem on AC house wiring, but not out of the question....

Check the voltage on the bulb when everything on the circuit is on.
 
For those who skimmed over and missed it, there are a number of the exact same recessed fixtures in the room, on the same circuit (classic on/off switch, not a dimmer, not a fan), using CFL's. Some as big as 300 W equivalent.

All the rest of those are fine.

It is this ONE that is having a unique problem.

From some of the posts, it seems most likely it is poor contact in this one (IIRC, every time I replaced a bulb in that socket and screwed it in while the other lights were on, once the bulb lit up, I was not able to rotate it much farther).

So as I said, I'll try a bulb extender (about to leave to go shopping), modified for deeper contact, and see if that solves it or not.

I switched to CFL's from incandescents about 7 years ago and never looked back. Lower bills and the bulbs last way way longer (there was a "security light" I left on all the time in a room, which lasted 2 to 2.5 years, incredible) . Except for this one fixture, where clearly it ain't the bulb, it's the fixture..

One possibility George as to why this one is failing an the other lights are not is that the others have sufficient air space around them up in the attic (they should be covered with some form of insulation shield that keeps the insulation off the can directly) the insulation or the insulation standoff may not be allowing enough airspace causing just this one to overheat. Is the ballast portion have any kind of scorched appearing marks on the bad ones? WAG on my part but this scenario can happen.
 
For those who skimmed over and missed it

And that would be me! Oh well, the overheating info I provided is good to know anyway and I'm amazed you've been able to get good results even with a 300 W equivalent in a recessed fixture! The PDF I read a few years ago was searched for because I had early CFL failure problems in lamp trees, not even as potentially bad for overheating as unventilated recessed fixtures.

As has already been mentioned here, is that one recessed fixture somehow more insulated in the attic than the others? Basically, the one that's blowing early is acting as it should according to all that I've read about CFLs while the others aren't.
 
I also missed the 300w rating. The IC rated fixtures that I've installed over the years were all rated for a max of 75w for an incandescent bulb. I can't imagine 300w in a recessed fixture. Perhaps they aren't IC rated and could be overheating without any protection. It might not be a bad idea to check for any scorching up in the attic. I've also seen IC rated fixture that blow bulbs when there isn't enough insulation on top of the fixture in the attic. A blast of cold air can get through and sometimes break the filament of an incandescent bulb.
 
Stick a low watt incandescent bulb in it to see if it fails quickly. That should be a lot cheaper test than another CFL. Keep the wattage low to avoid heat buildup.

It sounds like a bad fixture or wired incorrectly based on everything you told us. If you don't know how, or can't fix it yourself, hire an electrician. I have added and replaced outlets and light fixtures, but only on 110 lines. Our dryer quit working last year and I tested the outlet and it was bad. I didn't even think of replacing it myself as it was a 220 line; I called an electrician. The same with the hallway light that went bad. It has two on/off switches. Too many chances to screw it up, so I called an electrician.
 
George, do you have access to above the ceiling these are in, so you can see the cans and the wiring? Like, is there an attic above that you can get into?

If so, you should be able to figure out if that particular can is wired differently than the other ones, or if there's something different about that particular fixture.

Either way, take a electric meter to all the fixtures and see what they measure. Just be careful! Electricity bites hard.
 
I also missed the 300w rating. The IC rated fixtures that I've installed over the years were all rated for a max of 75w for an incandescent bulb. I can't imagine 300w in a recessed fixture.
That's the 300W incandescent equivalent rating. A CFL with that incandescent illumination equivalency rating only uses 55 to 68W according to a search I just did.
 
OK, that makes more sense. I've installed 16 of these units since this summer in my house and workshop. If anyone ever has to do that then get one of those ceiling drilling jigs that allows you to drill in the ceiling while catching the drywall dust. They work really well.
 
Though I do like the CFL bulbs, I like the LSD bulbs, the colors are amazing :D

Ok, yea, I meant LED bulbs, but I do like the 'daylight' color. Almost bluish, but is very similar to actual daylight.

I had a similar problem with a light fixture a while back. I made sure the power was OFF, and I was able to bend the tang of the fixture down to make a better connection.

I found that was the problem while screwing in a bulb with the switch turned on. I could hear it arcing...
 
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The 300 watt bulbs, which are doing fine, as well as a few other 150’s, are CFL’s that have the light output equivalent of a 300 watt (or 150 watt) incandescent. I do not know the exact “real” wattage, but in doing some quick googling, it looks like a “300 watt” equivalent CFL draws way lower than 100 watts, indeed the ones I’ve found listed top out at 68 watts actual current for a 300 watt incandescent equivalent. The "150 watt" CFL that died this week, only drew 40 watts.

Anyway, good news. I added the bulb extender, after soldering about a 3/16” extension to the center contact of the extender base, and using a new “100 watt” CFL bulb (OK, technically it draws 23 watts).

PrDhY4P.jpg


5 hours later, it’s still going. So, it may be solved. Not properly “fixed”, but solved. Time will tell. And all things considered, if it does keep going fine, I’m going to leave it at “100 watts” and not try a 150 equivalent CFL again for that fixture. Now, if I decided later that I really did want more light from that fixture, I'd bite the bullet and get an LED bulb. But otherwise, LED bulbs are just too expensive for me, for now. But in 2-3 years, probably cheap enough to justify, sorta like what happened with CFL pricing. And given everything else, I highly doubt I'd really want to mess with changing anything on the fixture if it keeps going OK (If it ain't broke...no more, don't "fix it" any further). If it dies, then that's it, I won't try using that one anymore.

One nice thing that helped to pay for the bulb extender, a 3-pack of 100 watt equivalent CFL’s were on sale at the hardware store for about $3.50. I’d just gotten a 3-pack at Walmart for about $8.80. Got two of the sale priced 3-packs and dropped by Walmart again (It was near the hardware store) and got a refund for the CFL’s I’d bought there an hour before.

BTW - the workshop this is in, is underneath a garage with a poured cement slab. So, uh, no access from above the ceiling.... without using a jackhammer. :) And as it is, I've already invoked the "First, do no harm" physician's motto.

So, again, thanks for all the input on this. I'll give a status update in a few days if it's still working, or an update quickly if it dies.

- George Gassaway
 
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Poured cement slab? Don't you mean "concrete"?

Given that the word cement shows up in the dictionary as another (if slightly imprecise) term for concrete, his original post makes sense to me. While cement is technically just the adhesive portion of concrete, it is in common use as a word substitute for concrete.

God save us from the grammar police...;)
 
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