flickering lights :(

[glandix]

recently (i think i first noticed it a day or two ago), some of my lights in my house started randomly flickering (so random that it seems once you've got it figured out and all is good, it will flicker)... it doesn't seem to correlate with any appliance coming on and it only affects one circuit that is mostly just lights.

not much has changed recently, except that i did replace a hallway light on the same circuit. actually, i replaced two lights (lowes had a great deal on a 2-light set that looked really nice!), but one of the two new ones is on another circuit and does not flicker what-so-ever.

now, before you go blaming my wiring on that light fixture, it's been double- and triple-checked and i am 100% sure of the wiring on it.

also, it seems to only flicker when i either have the main bathroom lights on or the heat lamp on. it seems to do it more often with the heat lamp off, however. it flickers the most with the main bathroom lights on, second-most with the main bathroom lights and heat lamp on or just the heat lamp on ...

if i play around with the main bathroom lights by flipping them on and off, it seems to "aggravate" it and it flickers more when i'm doing that, then subsides ... sometimes (like right now), it's been on for a while and hasn't flickered at all! talk about frustrating to troubleshoot!

i know flickering lights is not a good sign and i'm about to flip off the power to that circuit and pull out the light switch to make sure nothing would be touching and all the connections are solid ... same with the light fixture that holds the main bathroom lights...

any other ideas? if possible, i'd like to try to solve/fix this myself (assuming it isn't a problem in the circuit box itself, 'cause i'm not ready to touch it!) because i know enough to reliably replace lights / switches / outlets, but this one's got me kinda baffled. my dad is willing to come up tomorrow to check it out if i can't figure out anything tonight and he knows quite a bit more than me about all of this ...

and, i'm not sure how much (if any) of this info is pertanent, but i figured i'd rather have too much info than too little:

- house built in 1956
- 3 switches in one for the bathroom light + heat lamp + vent
- box behind the light switch is plastic, not metal and the light switch has a ground attached to it (however, i honestly don't know if that actually leads anywhere or not, it is just how it was)
- all lights in the entire house are CFLs
- been using these lights for over a year without any problems
- only other thing on the same circuit that was recently changed is the doorbell button
- i don't feel/smell anything hot or hear any arcing (tho' i would suspect that if i heard it, it very likely would be tripping the circuit, too)
- no other lights in the house are affected, just the one circuit

[chandler]

It is possible it is the switches, or in the way they were wired. Turn off the power at the breaker box for a particular circuit. Pull a switch out of the box and see if the wires are wrapped around the screws or if they used the stab backs. If stabbed, use a small screwdriver and remove the wire and place it under an adjoining screw. Stab backs are notorious for causing flickering lights.

[glandix]

It is possible it is the switches, or in the way they were wired. Turn off the power at the breaker box for a particular circuit. Pull a switch out of the box and see if the wires are wrapped around the screws or if they used the stab backs. If stabbed, use a small screwdriver and remove the wire and place it under an adjoining screw. Stab backs are notorious for causing flickering lights.

haven't pulled it out yet, but i do know for a fact that they aren't the nasty stab backs and use the screws instead ... i actually replaced this switch about a year / year and a half ago ... i'm still going to pull out the switch here in a little bit to double-check everything ... same with the main light fixture ... just haven't gotten around to it yet this evening (got sidetracked in these forums :P)

[Wirepuller38]

Make sure all light bulbs are screwed in tight in their sockets.
A loose bulb is a loose connection.

[ibpooks]

You have a loose connection somewhere. If you're certain that only one circuit is affected, then that is where to focus your attention. If it's more than one circuit, you should call the power company ASAP as you probably have a loose connection at your service entrance.

The loose connection could be anywhere on the problem circuit, not just where the flickering fixtures are. First check the breaker and panel; make sure the breaker mates tightly to the bus and that the hot wire is firmly attached to the breaker. Also verify that the neutral wire is firmly attached to the neutral bus.

Next, you should systematically go through each fixture, switch and receptacle on the circuit and make sure all the connections are tight. Move any backstabs to screw terminals as you go. Also, with 1950s junctions, you may have twist-n-tape connections in the boxes that should be remade with wirenuts as you go.

[glandix]

cool, thanks for the tips. so far, all the joints that I've dealt with have been wire nuts + tape or just wire nuts alone, so someone must've been doing some upgrades over the years.

I am 100% sure it's only one circuit affected, fortunately.

So far, today, I haven't had any flickering, strangely. I removed and re-installed all lights in the main bathroom fixture and the hallway light I put up semi-recently. Would a loose bulb actually cause a whole circuit to flicker? I've never experienced that before. Would it be any different w/ CFLs vs incandescents?

I'm planning on going through all the connections tonight after work, so hopefully if a loose bulb wasn't the problem, I'll find it and be able to fix it.

[bigfred]

I totally agree with ibpooks, and would add one thing. As you're going through checking things look for a connection with black pitted wires, screws, etc. Black pitting of metal contacts tells me arcing, which tells me flickering...

[glandix]

I totally agree with ibpooks, and would add one thing. As you're going through checking things look for a connection with black pitted wires, screws, etc. Black pitting of metal contacts tells me arcing, which tells me flickering...

ahh, didn't think of that ... was going to make a note of any deformed/discolored insulation, but didn't think about the contacts ... i have replaced nearly all the outlets and switches in the house, so i at least know i'm starting off with good outlets/switches that aren't worn out or anything and i'm confident in my wiring of them. some of the boxes were really cramped, so those will be the first i check in case something got kinked funny. also, i did have to take down the light fixture in the bathroom a while back when i took down wallpaper and it was not an easy fixture to put back, thus making it my prime suspect. it'll be replaced eventually anyway (working on replacing all brass in my house with new brushed nickel ) ... if the flickering was caused by anything i did, my bets are on that fixture ... otherwise, i'll just see what turns up when i go over that circuit

thanks, everyone, for the great advice!

[jwhite]

See if the lights flicker when the wind blows.

The problem could be with the incomming utility lines overhead.

[lectriclee]

With those taped connections.. untape them and look, tape hides alot of things.
If you go thru each device you may find and fix it without even knowing. But it may be a matter of time before it returns. So check the wire nut connections good, give the wires a tug.

[glandix]

With those taped connections.. untape them and look, tape hides alot of things.
If you go thru each device you may find and fix it without even knowing. But it may be a matter of time before it returns. So check the wire nut connections good, give the wires a tug.

so far, i have only run into a few of them ... and all of the ones i've run into on the problematic circuit that i've seen are already replaced ... i have a feeling there are quite a few more in the basement, however ... but that's another circuit

speaking of making sure wire nuts are secure, do you have any suggestions on how best to make sure you have a good, solid connection when attaching light fixtures with stranded wire to the solid core copper of the house? solid core to solid core is really easy, 'cause i twist the two together, then screw on the wire nut ... the stranded to solid core aren't as easy (to me)

[lectriclee]

I strip each conductor back the same length, then I twist the strands with my fingers,(with power off), Then I just put them together and let the wire nut twist the rest. Use the right size wire nut, orange for 1 14g/1 fixture wire,or a yellow.
reds are typicaly too big for a fixture splice.

[glandix]

I strip each conductor back the same length, then I twist the strands with my fingers,(with power off), Then I just put them together and let the wire nut twist the rest. Use the right size wire nut, orange for 1 14g/1 fixture wire,or a yellow.
reds are typicaly too big for a fixture splice.

yeah, i just used the orange wire nuts it came with ... strangely, it came with two different sizes, both orange ... it is a 2x 60W fixture and each light has it's own black and white wires ... different than other, similar ones i've installed ... just to double-check (since the instructions were horrible) what would be the correct way to wire this with 5 wires (2x black, 2x white, 1x ground) on the fixture itself