When changing out a lightbulb in a cheap builder's grade (builder installed, 6 yrs ago) glass enclosed light fixture I noticed that the white wires inside the fixture are turning brown. I've always used the recommended wattage bulbs so I don' think that should have caused it. Is this normal or is something overheating and I should replace the fixture?

Wanted to add that we do leave this light on all day, every day. (turned off at night) It's our one light that we always leave on.

[This message has been edited by agswife (edited 7/25/2011 10:05a).]

I would say it is not normal. But switch the bulb to a compact flourescent and the heat generated goes down dramatically. And since you leave it on so much you'll probably save money.

Neighbor had the same issue. Turned out to be Chinese drywall. In a class action lawsuit now. Check the copper ground. If black you may have an issue

Chinese drywall is a pretty big leap here IMO (not impossible though I guess.) Sounded like she said the white insulation turned brown, which has nothing to do with Chinese drywall (which causes corrosion of the metal, not anything on the insulation.) Since it was brought up, you can check it by looking at a couple of other places - anywhere you would have exposed copper - pull a couple random outlet or switch covers and look at the wires (the bare ground wire is easist,) look under the cover in the breaker panel, look at the copper freon line at the attic ac connections, look at copper plumbing lines under sinks. CD off-gassing will cause the copper to turn a dark blackish blue color. You may also notice a strong sulfur smell in the house.

I think it sounds like a heat issue due to the fact you leave the light on all the time. Even with the recommended max wattage this could happen. Pretty common to see in older homes at light fixtures.

I would second Spicewood's advice on putting in a CFL or a LED bulb. That will reduce the heat and save you money on having it on so much.

[This message has been edited by Absolute (edited 7/25/2011 11:16a).]

I'm pretty sure it's not Chinese drywall. Probably the heat as others mentioned. I was refraining from using the CFL bulbs in this fixture because the box stated not to use in enclosed fixtures, but the GE website says that most enclosed fixtures are actually fine to use them in (except enclosed recessed lighting, which this isn't) so I'll try that. I may change out the light fixture anyways since I've never loved it, and would change it to a semi-flush mount where the bulbs can breathe and I'll feel more comfortable with a CFL.

thanks!

Take the fixture down and make sure the white wires are twisted well.

Is it turning brown along the entire wire, at the ends, or everything? Can you tell if it is like a residue that will wipe off, or if the insulation itself is discolored?

went ahead and replaced the fixture - the brown on the white wires was just from the heat of the bulbs. The only part of the white wires it was on was closest to the bulbs, so that answers that. As usual, not happy with the electricians that installed the light (should have already guessed that from the other things I've fixed in the home). The fixture was always wobbly against the ceiling, which I hated. When taking it down, obviously the installers thought it was wobbly also and stripped the screws trying to tighten it down, then gave up and left it wobbly. The new fixture ( http://www.homedepot.com/Lighting-Fans-Indoor-Lighting-Indoor-Ceiling-Lighting-Pendant-Lights/h_d1/N-5yc1vZbvlo/R-202064738/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053 ) is tight and secure to the ceiling.