I have this light fixture in the entry way from garage into the home. I have to replace one of the bulbs about every other week. Not always from the same receptacle (two screw-in things in the one fixture). One of the bulbs is always burning out much, much faster than I would expect. Same high quality light bulbs I use in the rest of the house.
It’s the main door we use to come and go, and it has a motion sensor on the wall switch so it comes on automatically when we enter, stays on for a few minutes, then turns off. It’s a standard ceiling fixture with two incandescent bulbs.
The light fixture is not on constantly, but even if it were, it still seems the bulbs are dying way too fast. Does the frequent on/off cycling shorten the light bulb’s life that much? Is there something wrong with the fixture itself?
Turning a bulb on and off a lot doesn’t really shorten the bulb’s life all that much–some, but not enough to make a huge difference. In cases like this, there are three main culprits: vibration, thermal cycling and overvoltage. Since you say it’s the main door you use to go in and out of the house, it’s possible that the vibrations from opening and causing the door are causing this. Try a bulb like this specifically designed for outdoor use with a vibration-resistant filament.
It’s also possibly a thermal cycling issue, which the aforementioned outdoor bulb should also address. Thermal tress causes almost invisible fractures in the glass envelope, particularly where the bulb joints the base, allowing ambient air in, which oxidizes the filament. This and vibration are the two most likely causes of premature bulb failure, particularly when only one fixture is involved, especially when the at fixture is outdoors or in an unheated space with large temperature swings, like a garage.
The other, less common, cause is overvoltage. It doesn’t take much to shorten a bulb’s life since the lifespan of a bulb is roughly related to the twelfth power of the applied voltage. If this is the cause of the problem, you’ll need an electrician to determine the root cause. the vast majority of the time, however, an overvoltage issue affects an entire circuit or the entire building, not just a single fixture.
I have found that bulbs that are close to doors will not last as long. The slamming of the doors jars the element in the bulb and can cause pre-mature failure. If the light is OFF it won’t matter as much, but if the light is ON then it magnifies the shock from the doors closing.
This is from experience (from being in electrical construction for many years). It doesn’t sound like a ‘fixture’ problem from what you describe.
No, you don’t. If the bulbs were on all the time, that might be a problem, but in this case they aren’t long enough to come to maximum operating temperature. Fixture wattage ratings have little to do with electrical issues; they are mostly related to how well the fixture withstands heat–in this case, the wattage rating is really a heat rating. Unless the fixture is designed to deal effectively with the waste heat, a higher wattage causes things like insulation breakdown and stress/cracking of components which create a potential fire hazard. The ratings are based on the bulb being on long enough to reach maximum temperature. With a short duty-cycle application like this, exceeding the recommended wattage rating becomes less problematic.
Thanks for the suggestions. More info to see if this helps:
The sockets are rated for 60 watts each and yes, I admit sometimes sticking a 75 watt bulb in. My thinking is, “Hey, one of these is going to be dead soon, so I can use an extra 15 watts to compensate until I drag the ladder out to change the damn thing.”
The fixture is actually indoors, in the entryway leading from the garage to the kitchen. So it’s not outside and doesn’t get cold.
It’s about three feet from the door to the garage and 18 inches from the laundry room, which has bi-fold doors. We aren’t much for door slamming around here, but does just regular door closing stress the bulb enough to keep killing it?
I installed the fixture myself, but I’ve done that dozens of times and there wasn’t anything tricky about it.
I’ve got a similar situation. The bulbs in my kitchen fixture seem to need to be replaced far more often than any other bulbs in my house.
AFAIK, all our lamps/light fixtures use appropriate sized bulbs. Though the kitchen fixture probably gets as much use as any light in our house, I imagine a couple of others (downstairs and upstairs hallways) get just as much if not more use.
Got kids, particularly somewhat rambunctious ones? Is their room(s) above the kitchen? If so, that’s a possibility right there. If not, what is right above the kitchen? Anything which causes a lot of vibration, such as certain types of exercise machines, can cause this sort of thing.
Just try to use the correct bulbs if you can, even if they never stay on long enough to get hot.
This is what I gathered from the OP, so the fixture itself was subject to vibration from two doors, except now we learn that only one is a typical door (the garage door).
Could. The garage door is probably a heavy fire-rated door and just the regular closing of it may be enough to rattle the filament in the bulbs.
How old is the wiring in the home/how old is the home?
FYI, the light fixture in the laundry room, maybe two feet from the one in question and just as close to the door to the garage, doesn’t have the same problem.
How difficult would it be to post a picture(s)?
I’d hate to say you’ve wired it wrong in some manner because usually you’d have to mess it up pretty bad for the wiring to be an issue in a light fixture. For instance, a really loose nuetral connection could cause arcing in the splice and periodic spikes through the lamp filament, but you’d (probably) also see intermittent blinking/dimming (which you didn’t report).
For peace of mind you should consider taking the fixture back down and re-checking the splices.
Also, is this fixture on a 3-way switch and if so, is the motion detector designed for 3-way control or did you modify the wiring in some fashion? Also, where is the motion sensor located (on the wall, replacing the switch?), and is it grounded?
FWIW, I read somewhere that filament-type bulbs (e.g. incandescent) are less vulnerable to shock & vibration when they’re on vs. off. This is because the filament becomes plastic (I’m using this term as an adjective) at a very high temperature, and is thus less brittle and less susceptible to vibration when the light is on.
No three-way switch. No wiring modification. Sensor is on the wall switch, and I assume it’s grounded. I don’t remember details of installing it, but I guess I would have grounded it. If not, how would that affect the situation?
If you’re thinking that vibration is an issue, head to your local hardware store and buy “garage door opener” light bulbs. They’re constructed to withstand vibration. See if they last any longer.
Yeah, it is a light/fan combo. Has (I think) 5 separate 40 or 60W bulbs. We have 7 fan/lights in our house, but the light on the kitchen one probably is on more than the other ones. The fan gets used most, however, only in the warmer weather. The kitchen fan/light has only one wall switch, and you pull 2 different chains to turn the light and fan on and off, or to adjust the fan speeds. The other ones in our dining room and bedrooms have 2 wall switches, one for the fan and one for the light, tho the chains can also be used.
My youngest daughter’s bedroom is right above the kitchen. She’s 15, tho, and not exactly rambunctious.
A couple years ago we installed a new, 12 ft. X 12 ft. shielded room in our lab. The room’s ceiling had four, flush-mount light fixtures. Each fixture could accommodate two, 60 W incandescent bulbs. I installed two 60 W bulbs in each fixture.
During the first year the bulbs were burning out on a frequent basis. I swear they didn’t last a month. It was driving me nuts. I checked the voltage; it was fine. The room was always around 70 °F, both inside and out, so thermal stress was not the culprit. And there was no vibration. Finally, the lights did not experience much cycling. We turned them on in the morning and off in the evening.
I FINALLY figured it out. It was mechanical shock!
The fixtures look a lot like this, with one exception: the globes are not held up by screws. The base plate has three spring clips equally spaced around its perimeter, and the globe is held in place by the clips. The clips are very stiff. When you install the globe onto the base plate (after installing new bulbs), it snaps into place and sends a large mechanical shock into the base plate and into the bulbs. I reasoned that this initial shock - the result of installing the globe - was killing the bulbs.
There wasn’t much I could do about the shock (short of installing new fixtures, of course). I tried and tried to install the globes in a slow and controlled manner, but the clips were so stiff that the globe would always produce a huge shock when it snapped into place. So I ended up installing bulbs that were “vibration resistant.” That was June of last year. And I believe none have burned out since.
You should get ‘rough service’ lamps for the fans.
They might just be labeled “ceiling fan bulbs” or something like that but we call them ‘rough service’ bulbs in the trade.
It shouldn’t effect the bulbs in any way but electronic controls like that should be grounded for proper operation and safety.
Crafter Man, the filaments breaking under stress while turned ‘on’ is merely annecdotal. It’s just from years of breaking lights while stapling romex to the studs that I learned that unscrewing the closest bulbs and then screwing them back in after hammering the staples to the studs always prevented them from failing. Usually, if I forgot to unscrew (or turn off, if enough amient light was present) the bulb and then hammered on the same stud the fixture was mounted to, the bulb would get temporarily brighter, and then after another hit or two it would stop working altogether. At first I started to remove the whole bulb, but after doing this a number of times and getting lazy I just unscrewed it enough so that it went out, then resumed hammering. This seemed to be enough to save many a lamp and trips out to the service truck.
