I'm in the dark, Charlie. Again.

May 23, 2009 11:06 AM

Light bulbs with short life spans + older house = scary wiring problem?

For years I've rented a small, old house. There are two rooms (bathroom and kitchen) with ceiling light fixtures. Very basic set up- two light bulbs screw into exposed sockets under a glass cover.

These lights are ALWAYS burning out. Maybe one bulb a month.

Other than being a huge annoyance (high ceilings, shaky step ladder, fear of falling and breaking my neck), every time another bulb goes POP, I wonder if there could be a scary wiring problem.


This doesn't happen with lamps that are plugged in. No problems with other appliances. Fuse has only blown once, years ago, while vacuuming when I had the AC unit running.

I'm using name-brand light bulbs. 60w or 75w max. As I mentioned, each light fixture has 2 bulbs- but they don't both go POP simultaneously, which eases my worry a little bit.

I should probably ask the landlord to inspect, but I hate to deal with him for any reason. He's a slightly creepy guy with absolutely NO home maintenance skills. Everything he's tried to fix around here has been a disaster. Also, he's very cheap and wouldn't spring for a qualified professional to do it. If anything, he'd poke around and make a mess and pronounce it 'fine'.

To prevent a fire, and the loss of everything I own, I'd happily pay a professional to inspect it myself. But I don't know if it's really necessary?

For those with electrical smarts: are short-lived light bulbs a sign of trouble?

posted by GuffProof to home & garden (17 comments total)

They are probably a sign of bad contacts in the fixtures, not bad wiring. Do you see arcing and burn marks (they might be slight) on the contacts in the fixtures?
posted by caddis at 12:26 PM on May 23

Hmmm. Good question. It's hard to get a good look at them (see: high ceilings) but when I've been up there trying to change bulbs, they seem old, dingy, grungy. Have not noticed any obvious scorching.
posted by GuffProof at 12:33 PM on May 23

Also, depending on how sturdy the house is, vibrations from walking on upper floors above the lights can make the filaments break prematurely.

I was having to change incandescent bulbs in my basement, some that I only turn on once or twice a month, about every 4-12 weeks also. I read somewhere about the shaky floors idea and it made sense. Something to keep in mind if you are in an old, multi-floor house or apartment. I switched to compact fluorescents in the basement, btw.
posted by glycolized at 12:48 PM on May 23 [1 favorite]

Do the lights seem substantially brighter than similar rating bulbs would be elsewhere in the house?

I wonder if they're miswired and receiving two "hot" lines, instead of "hot" and "common". That would mean they were getting... (um) something like 140V instead of 110V. (I'm too lazy to do the math to figure out the voltage differential for two AC phases 120 degrees out.)

If that were the case they'd definitely have a shorter life. But they'd also burn a lot brighter than expected, too. Not just a little bit brighter.
posted by Chocolate Pickle at 1:46 PM on May 23

I am an idiot. The voltage differential between two hot phases is exactly the same as between a hot phase and common. Please ignore my previous post.
posted by Chocolate Pickle at 1:59 PM on May 23

This might help.
posted by Brian B. at 2:00 PM on May 23

Chocolate Pickle writes "The voltage differential between two hot phases is exactly the same as between a hot phase and common. Please ignore my previous post."

Actually the voltage between two hot legs (they are the same phase) is double that between a hot and neutral. That kind of mis-wiring will pop the bulbs immediately.

I'll throw in a vote for vibration. Try installing rough service bulbs. They are designed for trouble lights and garage door openers and have stronger filaments.
posted by Mitheral at 3:00 PM on May 23

Chocolate Pickle: Don't know where you reside, but in the US, the electricity coming into the home has two phases, 180° apart. From either hot line to ground is 120V. From one hot line to the other is 240V. A 120V light bulb wired between two hot lines would receive 240V and burn out in milliseconds. So, not a possibility for the OP.

I agree with caddis and Brian that it's likely poor electrical contact between bulb and socket (either dirty or bent contact). Unfortunately, fixing this problem while up on a tall, shaky ladder is quite dangerous for the inexperienced.

Also agree with glyco's possibility if there are people on the floor above walking around and jarring the light bulbs. Vibration definitely shortens bulb life.
posted by exphysicist345 at 3:00 PM on May 23

Thanks, all.

Glycolized, it's good to know that there might be a harmless explanation like vibrations. I live in a high-traffic area, so many things shake the house. No neighbors upstairs, though. This is a single-occupant house, one of the reasons I've lived here so long. Despite the many flaws of this place, the privacy and the absence of noisy upstairs or downstairs neighbors is precious.

Chocolate Pickle- I don't notice a difference in brightness. But it's entirely possible that someone miswired. There are a couple of light switches in this house where Off is up and On is down-- in other words, they installed it backwards or upside down or something. A close look around the basement shows a truly amazing patchwork and mishmash of pipes, wires, etc. I'm not sure the builders or later owners of this place had any idea what they were doing. (I don't know how old the house is, but I'm in an old, historic neighborhood. I'd guess 40 - 50 years?)

Brian B- very helpful link! I don't think I'm screwing them in too tight but it's possible. Installing bulbs while clinging to the stepladder is more or less terrifying for me, so I might be over doing it. Unfortunately there is no way for me to get close enough to the interior of the socket to inspect the brass part, but I will loosen the bulbs that are in there now and see if that helps!
posted by GuffProof at 3:04 PM on May 23

exphysicist345 writes "Don't know where you reside, but in the US, the electricity coming into the home has two phases, 180° apart"

Standard home power in the US and Canada is single phase, specifically "a 3-wire, single-phase, mid-point neutral system.
posted by Mitheral at 3:39 PM on May 23

I would put CFLs in and see if these very-different sources of light might react differently to whatever is making your edison bulbs die.
posted by floam at 4:32 PM on May 23

Yes, standard home wiring is single phase + neutral. But if you pick two outlets, wired to the two different hot wires, you have 220V of potential between them. Ask me about things I found in my house that were SPECTACULARLY not up to code. What's being suggested here is that someone wired things wrong and made a 220V light socket which, yeah, will probably eat a light bulb much faster than described here, so is probably not the case.

If you're using regular incandescents, it might be that the fixtures are trapping a lot of heat and killing your bulbs by overcooking. So CFs might be the right answer.
posted by Kid Charlemagne at 5:18 PM on May 23 [1 favorite]

If you can afford it, I HIGHLY recommend getting a better ladder. As someone who spends the better part of some days on a ladder, I recommend the fiberglass ladders, especially the ones with steps on both sides. Much more stable than any creaky old wood or aluminum ladder I've used. Also, take the time to make sure all four feet are sturdy on the floor before you climb it. An easy way to do this is to open the ladder and put it where you want. Then pick up one side (a step side) a few inches, and set it back down again while pulling gently outward.

As for the wiring...do you have a multimeter or a friend with a multimeter? If so, take a look at the voltage coming out of the socket. Like folks have said, it should be no greater than 120 volts. If it's a little high, you can get bulbs to compensate for that. This page has got some 130 volt rough service bulbs that might serve you well.

(I am an electrician, I am not YOUR electrician. I work in theaters. Your house is not a theater.)
posted by mollymayhem at 5:50 PM on May 23 [1 favorite]

Our place was built in the late 80s and we had this problem. We called an electrician out...seems that the fixture was not installed properly and was causing an arc. He also said it was a good thing we called...could have caused a fire.

It was not very expensive, as I recall. Around $100?
posted by JoanArkham at 5:50 PM on May 23

High voltages occur, but that would be a bad local transformer, not your wiring. You could check the voltage anywhere in the house. If you must check it at the fixture do not try putting probes directly into the socket. It would be too easy to short things out by touching the sides with the probe on the center tab. Instead get one of those socket to outlet converters that let you plug an electrical plug into your socket. You can more safely put the probes into the separate slots in the outlet, but even here you do need to exercise caution so as not to touch the live probe. Anyway, I doubt you find anything with this, I am just providing some safety info in case you decide to try it.
posted by caddis at 6:11 PM on May 23

GuffProof - I just want to point out that Brian B's link wasn't necessarily saying that you've been screwing them in too hard. If they were screwed in too hard in the past it is possible that the tab is pushed flat and doesn't spring out when you try to use it now. Are the spaces both very moist? Corrosion in the fixture seems like it could produce a similar problem.

Good luck!
posted by meinvt at 6:15 PM on May 23 [1 favorite]

#1: having an electrician come out and look at this will give you peace of mind that no other solution will give you, so if you can afford it, do it. If they say it's safe, ask them what they'd recommend for your problem and consider that advice before reading on.

#2: once you've determined that it's safe, rough service bulbs and 130v-tolerant bulbs are both good solutions. It's also possible you're just running too hot a light bulb in too small/poorly ventilated a fixture; is there a sticker that says something like "Max 40Watt bulbs only"? Even if there isn't, consider putting in two lower-wattage bulbs and see what you get.
posted by davejay at 8:32 PM on May 23 [1 favorite]