we were looking up at our hanging light in the stairwell and discussing the fact that we need to replace a bulb when my wife hit the switch on the wall and one bulb dimmed and went out followed quickly by the other. So i figured all 3 are dead now. Than i noticed that the lights were off in one bedroom and one bathroom. Went downstairs and sure enough, the breaker had tripped. Reset. No worries. Go back upstairs. Replace bulbs. Works great. Later on. I go to turn on the hallway light and poof, out they go. Go downstairs and sure enough, breaker is tripped again. This time, when I try to reset it, it hums than pops back off. I had the wife turn the switch I turned on, to off. Flip the breaker and its stays.

So now, we are avoiding turning on the light in the hallway. What could cause this? A malfunctioning switch? Its a 3 way switch. Or there are 3 switches that turn on/off the light. Should I replace them and see if that fixes the problem?

I left a message with an electrician so I'm waiting for a call back from them. Thankfully they're usually good at the whole hands off approach. Meaning if they can tell me what to do over the phone they won't come out and charge me to tell me I need to replace the switches.

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Sounds like a dead short inside the switch. I've seen this happen on older switches.

If you are handy you can replace yourself or electrician can do in less than an hour.
I would replace as a pair - just remember to mark your wires so you know which is the traveler.

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Edited 1 time(s). Last edit at 01/08/2010 07:09PM by lafinfil.

I've replaced many switches in this house for one reason or another. Heh. The hardest part is figuring out which breaker to turn off.

With that said, I had my wife try 2 of the 3 switches while I was downstairs in the closet and both times they tripped the breaker. Could this be just b/c they are linked or could both switches be hosed...at the same time. FYI: I didn't try the 3rd one. I figured I'll just leave it alone for now.

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lafinfil
Sounds like a dead short inside the switch. I've seen this happen on older switches.

If you are handy you can replace yourself or electrician can do in less than an hour.
I would replace as a pair - just remember to mark your wires so you know which is the traveler.

I replaced a two-way switch for one of our hallway lights and it was really easy, but like Phil said, make sure to label the wires so that the two/three-way will work as it is supposed to.

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Roswell, GA (Atlanta suburb)

I'm gonna ask a dumb question.
Is your breaker box in a dry location, IE doesn't get major damp at any time during the year?

2nd, is your house wired with aluminum or copper or both?
If there is untailed alum to any switch or fixture, it could cause oxidation/corrosion at the fixture or switch screws. That can cause breakers to pop.

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Fritz
I'm gonna ask a dumb question.
Is your breaker box in a dry location, IE doesn't get major damp at any time during the year?

Nope. Its in a downstairs closet. Nice and dry.

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Fritz
2nd, is your house wired with aluminum or copper or both?

All copper.

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bazookaman
With that said, I had my wife try 2 of the 3 switches while I was downstairs in the closet and both times they tripped the breaker.
Could this be just b/c they are linked or could both switches be hosed...at the same time. FYI: I didn't try the 3rd one. I figured I'll just leave it alone for now.

Sounds like it is shorting to the ground. The grounds are all connected so I believe this
could cause the second switch to trip the breaker as you describe.

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If there are 3 (three) switches controlling the same light fixture(s) you'll need a 4-way switch for one (the middle one; figure that out) and 3-way switches for the other two. You could replace one at a time looking for the bad one, but for the cost -- and safety if they're all the same age -- I'd say replace them all.

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MikeF
If there are 3 (three) switches controlling the same light fixture(s) you'll need a 4-way switch for one (the middle one; figure that out) and 3-way switches for the other two. You could replace one at a time looking for the bad one, but for the cost -- and safety if they're all the same age -- I'd say replace them all.

This is correct. 1 at the bottom of the stairs. 1 at the top. And 1 at the other end of the landing.

so i need one 4-way and two 3-ways?

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bazookaman

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MikeF
If there are 3 (three) switches controlling the same light fixture(s) you'll need a 4-way switch for one (the middle one; figure that out) and 3-way switches for the other two. You could replace one at a time looking for the bad one, but for the cost -- and safety if they're all the same age -- I'd say replace them all.

This is correct. 1 at the bottom of the stairs. 1 at the top. And 1 at the other end of the landing.

so i need one 4-way and two 3-ways?

3 locations would require a 4 way switch

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bazookaman

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MikeF
If there are 3 (three) switches controlling the same light fixture(s) you'll need a 4-way switch for one (the middle one; figure that out) and 3-way switches for the other two. You could replace one at a time looking for the bad one, but for the cost -- and safety if they're all the same age -- I'd say replace them all.

This is correct. 1 at the bottom of the stairs. 1 at the top. And 1 at the other end of the landing.

so i need one 4-way and two 3-ways?

Yes, in M>B>'s diagram, left and right are 3-way, middle one is 4-way.

Don't overlook the fact that there could be a short in the wiring. However, the best bet is to assume it's the switches. Rather than hunt for the bad one I'd probably plan on just replacing them all but then test after each replacement.

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"In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion." (1987) -- Carl Sagan

Remember that with three way and four way switches, operating one of them, even if it's not the defective switch, will cause the defective switch to impact the circuit. The switches are in series.