[TexasEd]

I have a set of 6 can lights on a two-switch setup in my kitchen.

I had a problem with the incandescent bulbs burning out in 2 of the fixtures in a couple of days. It was always the same 2 fixtures. Using "long life" halogena bulbs they lasted for a week or two.

I switched to CFL floods and they last for 1-2 months.

I'm calling a friend who is an electrician, but do you all have any ideas?

What should I troubleshoot for?

 

[Grampa Bud]

It sounds like a heat problem combined with a can fixture that is too closely insulated and can not gain sufficient cooling. Do you have bulbs at or below the rated wattage for the fixture?? Can you get at the fixtures from up above?? If not go online to LEDLIGHT.com and look up household LED bulbs. They have 3 and 5 watt bulbs that are every bit as comparable as 60 watt halogen or 40 watt CFL bulbs and they do not get warm.

 

[TexasEd]

The CFL that popped last night did so after it had been off for 5 hours. It audibly popped when I turned the switch on.

Also these lights are in the space between the first floor and the second floor. I do not expect there to be insulation there but I will check.

 

[Yoyizit]

I have a set of 6 can lights on a two-switch setup in my kitchen.

I had a problem with the incandescent bulbs burning out in 2 of the fixtures in a couple of days. It was always the same 2 fixtures. Using "long life" halogena bulbs they lasted for a week or two.

I switched to CFL floods and they last for 1-2 months.

I'm calling a friend who is an electrician, but do you all have any ideas?

What should I troubleshoot for?

Higher than normal voltage [126v to 132v], but it can't be as high as 240v or they wouldn't last that long.
Vibration due to people stomping around or due to resonance with machine vibrations?
Abnormal temp. in just those two fixtures?
Loose connections/bad wirenuts in just those two fixtures?

 

[thefamouscbc]

The CFL that popped last night did so after it had been off for 5 hours. It audibly popped when I turned the switch on.

Also these lights are in the space between the first floor and the second floor. I do not expect there to be insulation there but I will check.

Here are a few things I would look at.

First thing I thought of was too much insulation around it. If the can lights can't breathe, they will NOT work correctly. Bud was correct. I have saw contractors put insulation between two floors a thousand times. Yours should have it there.

Second take the can apart from the inside and get to the make up inside the junction box. Get a meter and check your voltage from Hot to Ground, and Hot to Neutral. You should be anywhere from 115v to 125v.

Third it sounds like maybe could be a loose neutral. Take all the wire nuts off the wires and replace with new Ideal tanny wire nuts. http://www.foxelectricsupply.com/co...Detail.asp?qsCatID=26491&qsProductNo=IDE30341

Also check your socket where the bulb screws in. Make sure it looks clean and nothing is broken inside it.

Get back to me and let me know if any of those worked.

 

[PaliBob]

Here is a recent similar thread
http://www.diychatroom.com/f18/recessed-light-lamps-burning-out-41636/

Note on the chart that for this can the manufacturer says 40W max for Incandescent bulbs (A19)

 

[Yoyizit]

What I don't get is, are the two that burn out the problem, or are the four that don't burn out the real symptom [that is, all six should be burning out and the ones that aren't are especially hardy]?
This problem doesn't seem possible which means I, for one, am assuming something that isn't true.

 

[PaliBob]

Are the 2 problem cans IC

Could the installer have put in IC cans at the problem area?

This manufacturer not only severly restricts lamp wattage and envelope but also makes a point:

For use with 120V
Incandescent lamps

Nothing in there about CFL's

source:
http://www.cooperlighting.com/specfiles/productinfopdf/H7RICT_RICAT.pdf

 

[AllanJ]

I contend that a CFL will work anywhere an incandescent of the same voltage and wattage will work assuming a direct connection to power (i.e. no electronic gadget such as a dimmer in between).

 

[TexasEd]

The other thread has me wondering about the bulb size as well. I am using what the builder installed for the size of the bulbs, but they could have installed the wrong size. I have been using BR30 floods. I'll remove the bulbs to see if I can find a model number on the cans to look up the recommended bulbs.

I will also check to see if all the cans are the same model. (I think it would be bad to assume they were)

 

[TexasEd]

Alan,

There are no dimmers on this circuit.

 

[Yoyizit]

I contend that a CFL will work anywhere an incandescent of the same voltage and wattage will work assuming a direct connection to power (i.e. no electronic gadget such as a dimmer in between).

Except for starting temp. restrictions which don't apply here, I have to agree.
The lighter current draw may cause switch contacts to self-clean less effectively, but that is also not a factor here.

 

[kbsparky]

You have bad sockets. Loose connections on the rivets that hold the screw-shell assembly together can overheat and cause premature failure of bulbs. Even CFL's can literally cook to death. :yes:

Replace the socket assembly, and your problem should vanish. :whistling2:

 

[Yoyizit]

You have bad sockets. Loose connections on the rivets that hold the screw-shell assembly together can overheat and cause premature failure of bulbs. Even CFL's can literally cook to death. :yes:

Replace the socket assembly, and your problem should vanish. :whistling2:

Can loose sockets be confirmed by inspection? Is this a factory defect?

 

[kbsparky]

Sometimes, you can see scorch marks on bad sockets. Loose fitting screw-shell or bottom tab flattened out and cracked can also be determined by visual inspection.

But not always.

As for factory defects, maybe. But how old are these fixtures anyways? More likely worn out from years of service. :whistling2:

 

[PaliBob]

....... More likely worn out from years of service

I get the impression that the house is new (≤ one year)

Post#10
....... I am using what the builder installed for the size of the bulbs, but they could have installed the wrong size. I have been using BR30 floods. I'll remove the bulbs to see if I can find a model number on the cans to look up the recommended bulbs.

I will also check to see if all the cans are the same model. (I think it would be bad to assume they were)

When Texas gets back to us hopefully he will have removed the trim and looked up into the can to see whether or not it is the same can as the four that do not have a problem. AT the same time he can remove the bulbs and with a strong flashlight inspect the lamp sockets for discoloration or contact erosion.

My hypothesis is that the builder, either by accident, or on purpose installed IC cans (which have tighter restrictions on wattage and bulb type) at those two locations.

Another possibility is if the Trim is different on the two 'problem' cans as compared to the four 'good' cans. And finally there is the chance that the builder just used cans with cheapo sockets that have failed.

 

[TexasEd]

Had a buddy who is an electrician out yesterday and he thinks there might be bad bases in the cans. His theory is that there might be a bad connection somewhere causing shunting. He is going to replace the two bases in those two fixtures.

I am embarrassed to say that the lights that were burned out were actually incandescent. I am sure we had fluorescent in them at one time and they must have been replaced. I know for a fact that we have blown at least one, probably two fluorescent lights out of them.

The fixtures did appear to be IC fixtures. I have not compared them to the other fixtures.

 

[TexasEd]

The house was built in 2006. New neighborhood with buried utilities. The transformer is one house over.

The bulbs that have burned out were within the specs of the cans. 65W BR30
I will replace them with CFL bulbs again once we have the new bases/sockets.

We also have poltergeist in the electrical system where bulbs start humming and we can pick up electrical noise on the baby monitor at the same time. So my friend left his meter on a circuit to check for over voltage over a period of time.

Could the poltergeist in one part of the house be caused shunting in another part of the house?

 

[TexasEd]

Voltage checked out at a max of 124 over 12 hours.

Going with the theory that we have bad bases and going to replace them.

 

[Yoyizit]

We also have poltergeist in the electrical system where bulbs start humming and we can pick up electrical noise on the baby monitor at the same time.

Can you put the electrical noise, and the humming, on YouTube? I'd like to hear that.
How does your friend define "shunting"?

124v into 120v incand. bulbs should give you ~60% of normal lifetime.