Light bulbs burning out frequently? Put on your detective hat!

This is the final contribution to this topic although from time to time I might add something else as this problem happens and the cause is not always apparent.

Just as a follow up, I was at my customer with the track light problem (ironically for another lighting issue – he has had bad luck with lighting in his not too old  5 year old house) and he let me know none of the LED bulbs for the track lighting has burned out.  LED has come a long way in reliability and the costs are going down but this is a topic for another day.

I had another situation with a customer where the light bulb in a particular fixture kept burning out, often within a week of installation.  It was a pot light that used PAR 30 bulbs and she was trying both fluorescent and incandescent bulbs.  You might say if you read the previous article on this topic that I should have just recommended an LED bulb to solve the problem.  Perhaps, but really incandescent or fluorescent should be fine and LED would not necessarily fix the problem.

Again, I put on my detective hat and ran down the list of possible causes:

Higher than normal voltage in house (ie. > 120V). – Meter showed within acceptable range (ie.  +/- 1 – 2 %)

Bulbs screwed in too tightly. – Tried brand new name brand bulb and screwed in myself.  Customer called next day and said was burnt out.  Arrghhh!

Excessive vibration in bulbs.  None apparent.

Bulbs getting too hot.  No.

Use of cheap “dollar store” light bulbs.  Maybe in past, but I had asked her to get a name brand for the test.

Fixtures or wiring not properly installed (eg. loose wiring)  – I checked all connections at light fixture and the two 3-way switches controlling the light.

I was at a dead end until the culprit in this maddening case made a mistake (hope you don’t mind the melodrama).  I kept asking the customer if there was anything unusual at which she assured me nothing was awry.  We then tried a different brand of bulb which burnt out a couple of days later but this time she had a clue.  When she used one the of switches there was a “popping” sound just before the light blew (and it wasn’t the light popping).

From this I surmised it could be the switch.  Normally basic light switches should not cause problems with the lights but I have had a number of customers in the last couple of years requiring a 3-way switch to be replaced that were not too old.  One of them actually noticed a spark coming from the switch when she turned on the light.  Do 3-way switches wear out faster than regular 1-way (single pole) switches?  That is a future article.

In this situation I replaced the 3-way switch and I have not heard back from the customer in over six months.  Case closed!  So, does this problem fall under the list of the most common reasons for premature light failure?  I would say yes, fixture or wiring not properly installed.  The 3-way switch may have had loose/faulty connections in the switching mechanism causing the bulbs to burn out.  An electrical engineer could give you an exact explanation of the physics involved if you are interested.  I am just the detective.