Durability of small screw in flourescents...?

[Kenneth]

Howdy,

We use many of the (currently popular) screw in fluorescent bulbs.

We often get 'em at Home Depot, and they have a seven year replacement warrantee.

None have lasted more than two years, and, to date, we have received on the order of two dozen as warrantee replacements. The manufacturer does not even ask that we return the failed bulbs.

More than a few have failed in less than a month, and since the first of those, I mark 'em with the date of installation and the date of failure.

When I first noticed the very short MTBF, I called the manufacturer's tech folks. The first thing they asked was for a description of the fixtures that hold them. They are (mostly) ceiling cans of the sort that are closed on the top, and open on the bottom. When I provided that answer, I was told that such an installation should not be affecting the length of life of the bulb.

So, I have become curious...

How long do these things last for others out there?

Many thanks,

[ransley]

Heat does kill the electronics faster. I have about 60 HD cfls going for 2 years, one that blew was in an enclosed ceiling light. Ive only had 2 failures. Your fixture is holding the heat, but you have a 7 yr warranty. Do you just go back to HD or do you have to mail them in.

[Kenneth]

Hi again,

I should have mentioned that last issue...

The first time or two that I accumulated a half dozen, I just took them with me the next time I went to HD. I brought them to the returns desk, and two minutes later left with a stack of new bulbs.

Then, when I went to do that again, a manager got involved and made a very big deal of it telling me that I had to contact the manufacturer.

I did that, and then replaced the bulbs with no hassle. IIRC, they asked on the first occasion that I send them back, but after that they just asked me how many had failed.

All the best,

[Malcolm Hoar]

I installed a whole bunch (~25) a couple of years ago and only one unit has failed thus far.

I do seem to have bad luck with flourescent tubes; they always seem to fail prematurely. And, yes, I always replace both tubes in a two-tube fitting at the same time. Usually, I replace the ballast too.

It's a bummer since replacement and disposal of the dead bodies is a significant hassle.

[KLS]

[CUT]

We've been in this house for 6 years, also about when we started using these compact flourescent bulbs, and none have died yet. They're also all Phillips or Sylvania (I don't think we have any GE bulbs). One older Phillips CFL has to be 7 years old and is lit every night for more than 5 hours at a time. We don't use these in short duration on/off situations, like bathrooms or the front porch, and we don't have flaky power in the house. No complaints.

[ransley]

Maybe you have voltage problems and surges, but heat is the likely cause.

[JIMMIE]

Ive done some failure analysis * on some of these and found its the electronics that usually fails. I dont doubt that they would work for

7 years of normal use if the elctronics wasnt being operated at its limits.

• I cracked them open to see what smoked.

[Anonymous]

I've been using the GE cfl's sold by WalMart.

The light color is excellent. ( none of that "corpse blue" lighting )

Haven't had a failure yet.

I think that overheating would cause premature failure. Problem comes up with fixtures that cover the lamp with a complete glass ball. ( as in bathroom fixtures )

[bob haller]

I blew a CF once while waxing a lamps wood piece, some of the spray must have gotten to the lamp, poof smoke:(

I never do that now, spray cloth apply to wood spindle on lamp

[bob haller]

my pole lamp ate CFs in the summer so I added a couple washers between the glass holder part and top which allows some air flow.

CFs last longer

[stan]

=A0 =A0 =A0 =A0 Gary Player. |

=A0 =A0 =A0 =A0 =A0 =A0|

That's strange! I rarely replace both tubes, and in fact just take from a stack of 40 or 50 old used tubes from a school renovation project. occasionally one of the used tubes will be bad, but infrequently. Also; only occasionally replace a ballast (again have stack of 'used' spares) and only in very old decrepit/use/second-hand fixtures that we 'fix-up' to use over work benches, garage etc. Have never replaced ballast in any of the new household/kitchen fixtures. So far have never needed to replace an 'electronic' ballast, got a couple of them spare as well! We are 115 volt 60 hertz AC here.

[Kenneth]

Hi,

I'm the OP, and mine are in vertical cans that have an open bottom. Perhaps they are overheating, but on average, I get

6-8 months.

All the best,

[ransley]

Try the Floods they are designed for heat

[sym]

my bulbs are in enclosed ceiling fixtures for 4 years now and have repleced none of them they all work as well as the first day they were installed, i wonder if you might have a voltage problem that could be shorting the life of your bulbs. just a thought.

[Kenneth]

And a reasonable thought it is...

We live in a rural area, and indeed notice power fluctuations. Nothing serious, but we do see it.

Also, we heat geothermally, and have a pump on our well that is the size of a locomotive. When that thing kicks on we see a brief (and slight) dimming of incandescent bulbs. I know that the pump is a huge voltage draw.

It might be possible that those fluctuations in voltage are enough to make the fluorescents unhappy.

Thanks for your comments,

[David Combs]

Electronics are where? In the base of the bulb, I guess.

So, when bulb is in ceiling light, pointing straight down, heat goes up to -- the electronics?

[David Combs]

I kept reading this thread-title (before actually getting into the thread itself) as being about some small screw inside (office-ceiling?) flourescent-fixtures, giving some kind of problem.

Really!

(Well, my brain-type gravitated me towards an engineering major -- you know, pencils in pocket (in a POCKET PROTECTOR, for god's sake! (Ditto for today)), etc, and of course take spoken/written words LITTERALLY -- assuming that what's written or said was carefully constructed so that I could do just that.)

(Heck, I was married (one year only) to a print-reporter then tv, etc, all of whose friends were also English-majored types -- NONE of whom could tolerate the thought of someone with pencils in a shirt pocket, ...)

(Current wife (of ~30 yrs) says sentences that mean one thing if taken literally, but expects you to be able to figure out what she really means!)

Anyway, the hyphen would certainly help.

For possible thread somewhere: why is it that lawyers rarely if ever use hyphens in contracts, etc?

David

[David Combs]

So you're saying that CF's are MORE sickened by heat than incandescent bulbs.

(I mean, look at fixtures for incandescent bulbs, like in a ceiling light in eg a bathroom -- enclosed, only wee holes for air flow, must get PRETTY DARN HOT in there!

David

[pheeh.zero]

e:

I have some CFLs in totally enclosed explosion-proof fixtures...but they are "on" 24/7 and have lasted more than 2 years. So yes, on/off cycles will shorted their life-span.

[trader4]

First, I've seen some CFL's that specifically state they are NOT to be mounted with the base up. I presume that is a heat issue. I/ve bought a variety of brands and had pretty good results overall. I have the sprial type in my garage now for several years and none has burned out. At least some of these are the ones you're not supposed to use upside down, but they're still OK anyway. Could be that upside down in the garage they still have lots of airflow and also usually aren't on for hours on end.

The worst results were with some of the ones that look like indoor floods and are in that form factor, not the open spiral type. Many of them failed within a few months. I don't know which ones I have now, but they have lasted for at least a year. Only problem with them is they take a good 2 -3 mins before you get any reasonable amount of light out of them. That's one of my pet peeves. If I could pass a consumer law, it would be that the manufacturer's have to spec how long it will take the bulb to get to say 70% of it's rated output.