Return to the Lighting Forum | Post a Follow-Up

CFL issues

Posted by sjpoolowner (My Page) on
Sun, Nov 14, 10 at 0:32

Hi all,

I had a contractor install recessed lights (CFLs) in our living room and noticed a couple of things, which concerns me. The CFL bulbs used are plug-in type with 4 pins, 26w ones. IC-rated casings for CFLs where used since we have insulation in the attic (Halo H272RICAT)

(1) I noticed that when I plugged in a bulb, the bulb flashed (turned on and then off really quickly) even with the switch off. I actually noticed this a few times with different sockets. Is this normal or does this indicate some bad wiring?

(2) This evening, one of the lights suddenly went off. I was suspecting the bulb was burnt out (it was a brand new one though) and tried it into another socket, but it was actually working okay. So I plugged it back in and turned on/off a couple of times, but each time it went off after being on for a short amount of time.

Then I realized that the casing has some thermal protection and thought it might have been overheated (although I didn't turn it on for a long time). So I waited a little and tried again. This time it went off again immediately and I actually heard some noise, so I checked the bulb and found that it got cracked.

So I removed the bulb and put another one in there and it is working okay till now.

Should I worry? Is it not rare that a CFL bulb gets cracked when turned on? Also, can it be overheated easily to have thermal protection to kick in? Or some bad wiring can cause overheating as well?

I am not sure if it was due to some shady work by the contractor or I am overreacting over something that is normal and expected for CFLs. I'm a novice in this area, so any help would be appreciated. Both incidents concern me greatly.


Follow-Up Postings:

RE: CFL issues

1. Most likely the capacitors in the fixture's ballast held a bit of a charge, enough to power the bulb for a fraction of a second. I wouldn't worry about this.

2. I have had CFs crack, though I don't know the cause. It is pretty rare, in my experience, but it does happen. Yours might be an especially cheap brand (just guessing). Again, I don't think it's a particularly big deal.

Make sure you dispose of the cracked lamp properly. I put my spent CFs in a box on a shelf in the cellar. When I have enough of them to make it worthwhile, which is every few years, I take the box to my local household hazardous waste disposal site.

RE: CFL issues

Thank you for the reply, David. The bulb was from Sylvania, so it is not really a cheap brand. But I understand cracks happen. Maybe it could be from my handling, but I am not sure.

I'm still a little bit concerned about overheating. I had turned it on for only about an hour or so before that happened. The other lights were all working fine. Maybe the protection logic in that can is more sensitive than the others. I guess it should be okay as long as it was not caused by a bad wiring or some other problem.

Thanks again.

RE: CFL issues

Well, CFs don't generate much heat, so I don't think overheating is too likely to be the cause. I suspect (but of course I can't prove!) that your bulb cracked because it had a factory defect.

If you had the lights installed fairly recently, you might call the contractor and ask about exchanging the cracked bulb for a new one.

RE: CFL issues

Oh, I was talking about overheating because the light initially went off w/o cracking the bulb after being turned on for about an hour. I was guessing it was due to the thermal protection of the can. Then, as you mentioned, CFL doesn't generate much heat and I was wondering if it is normal to go off after just one hour of use (I have 8 installed and only one had that problem) or if it implies any problems in installation or material itself.

The bulb got cracked after I turned on/off the light a few times after the incident.

RE: CFL issues

I see a couple of possibilities. One is that the ballast in that one can is overheating; another is that the thermal protector is a little hypersensitive.

Try it for a while with a known-good bulb. If it continues to act up, I'd say tat since it's a relatively new installation you should drag your contractor back to the house and tell him or her to make it right.

RE: CFL issues

Are the CFLs labeled for base up if they are in a can light?

While they do not generate a lot of heat, most of the heat is generated in the electronic ballast in the base of the bulb.

Not all are designed for base up operation.

RE: CFL issues

Brick, if I'm reading the OP correctly, these are CF cans, not retrofits. The ballast is in the can, not the base of the bulb - I think.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Lighting Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here