Lighting Nuisance

     Every now and then an electrical issue surprises me. Sometimes its because of where the trouble is located, other times, its due to the extent at which the problem has spread.

But in a recent experience the thing that surprised me most about the situation was how ridiculously easy the trouble was to fix. I'll explain.

The problem began with a circuit breaker tripping, thats when an internal safety feature is triggered inside the breaker and power is instantly cut off. According to the homeowners this started just after the backyard light fixture was replaced.

After gathering a little more information I began my troubleshooting at the obvious place first, the new light fixture.

Once the fixture was removed I checked for any indication of a problem. I looked at the wires, wire-nuts, back of the fixture, and the internal space of the junction box the fixture was attached to. Nothing.

The cause of the tripped circuit breaker was not the new light fixture, it was clear that an important clue had somehow been missed. Whenever an electrical problem comes up it usually follows one or more clues just before it fails.

 With little else to go on the next step was to go through and systematically rule out likely causes along the circuits path. From one junction point to another I checked for any signs of arcing, soot and burnt plastic smells.

With the above now scratched off the list I focused on the bedroom switches and fan/ light fixtures. Why? Because it was the only things left.

Since the Master bedrooms switch junction box contained the wiring for both bedrooms I decided to isolate and test the adjoining room first. With the circuit breaker OFF and Master bedroom wires removed the adjoining room was ready.

Power back ON I was able to get the ceiling fan and its lights working without any trouble, I then turned ON the backyard light to see if this would trigger the problem. Nothing. Everything seemed to work fine.

With the circuit breaker OFF again the adjoining bedrooms wires were removed and the Master bedrooms wires were connected. The circuit breaker was turned back ON and quickly shut OFF. The problem was now isolated to the Master bedroom.
 
Leaving the switch connected and the breaker in the tripped mode I next focused on the wires between the switch and fan/light fixture.

The Fan/ light fixture had a remote control receiver that was wired in at the ceiling junction box, after carefully removing it I decided at the last minute to remove the fan/ light fixture altogether.

With everything out of the way, I tested again. No trip. With power and the Master bedroom switch still ON, the backyard light fixture was also turned ON. No trip.

 With the power back OFF,  I reinstalled the ceiling fan but this time wired it without the receiver. The goal was to do a quick test. Power back ON, I ran through every sequence I could think of to get the circuit breaker to trip, but it wouldn't. The only thing removed from the original equation was the remote receiver.

The problem had now appeared to be found. The homeowners decided they could live without the remote so I closed everything up and left. My accomplishment was short lived, within a few hours the problem would return.

A little frustrated, I returned to the home and pulled the Master bedroom fan/ light fixture, apart. I retraced my steps and went over every detail, I double and triple checked my work to see if anything had changed, it hadn't.

Since I was now confident as to where the problem was I left the switches alone and allowed the wires in the junction box to stay connected. With the circuit breaker reset, I tested the bedroom light. Just like before the power shut off instantly. Without hesitation I went back out and reset the circuit breaker, I forgot to turn OFF the light switch in the Master Bedroom so when the breaker reset the light immediately came ON.

During the entire process I hadn't thought to leave the switch ON, seeing an opportunity I decided to run through a test. With the Master Bedrooms light still ON I went over to the adjoining bedroom and turned the lights on. No trip.

I went over to the backyard light switch and turned it ON. Still no trip.

Back in the Master bedroom I turned the switch OFF and ON sure enough the breaker tripped. Leaving the switch ON again I reset the breaker and this time tried controlling the fan/ light fixture using the pull chains attached to the fixture.

When I pulled one of the chains the circuit breaker tripped, but just before it did that two very distinct things happened. First, the light assembly at the bottom of the fixture was noticeably loose so when I pulled down the light assembly shifted sideways.

The second thing that happened was one of the bulbs flickered.

In disbelief, I quickly unscrewed the light assembly and checked the wiring harness when nothing was found I put the light assembly back and secured it properly.

Now that the light assembly was taken care of I moved on to the bulbs themselves. I recall seeing two bulbs and one of them flickering just before the breaker shut off. Well the funny thing was that this particular fixture had three bulbs.

Still in disbelief but eager to get this resolved I reached up and snugged down all three bulbs. For good measure I went into the adjoining room and did the same with those bulbs. When I turned the circuit breaker on this time everything on the circuit stayed ON.

So what was the problem exactly? Loose bulbs. Thats right loose bulbs but thats not the whole story you see normally a standard circuit breaker wouldn't flinch at a small arc like those you may find in a uh oh I don't know lets say loose bulb. But, the homeowners didn't have a standard circuit breaker they had what is called an Arc Fault Circuit Interrupter or AFCI.

AFCI's were put in place to help prevent small arcs from becoming big problems, unfortunately they don't decipher between a loose plug in an outlet and a loose bulb in a light socket.

Because of electrical code requirements AFCI's are going to be the industry standard, with that said, some of the ways homeowners can help avoid this situation is by being more informed and aware of the things that cause this type of trouble.

For those of you reading this article you can scratch that off your list.

The next thing you can do is home maintenance, if you know a bulb is flickering check it out and if need be, replace it. Another thing that led to this problem was an unbalanced ceiling fan, if your have a fan/ light fixture and its noticeably wiggling do some online research and find out how its supposed to work.

If your handy you can learn how to balance the ceiling fan yourself, its not hard and most anyone can do it themselves in a short period of time.

I hope you've enjoyed the article if you have any questions or comments feel free to share them below. Until next time be safe.