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  #16  
Old 12/3/08, 8:26 AM
Jim Port Jim Port is offline
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Default Re: Flickering CFL

Up and down in regards to 3 way switches has no meaning. Either position can be on or off depending on the position of the other switch.
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  #17  
Old 12/3/08, 8:45 AM
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Default Re: Flickering CFL

Quote:
Originally Posted by jkogel View Post
Does anyone have an answer to the original question?
It sounds like one of the switches is actually on, bad or loose bulb, but switch is in the down position because it's a 3-way circuit.

John Kogel
www.allsafehome.ca
Paul is right in changing the bulb first as it could be many things.

I have seen dimmer switches that look like regular switches.
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  #18  
Old 12/3/08, 9:24 AM
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Jeffrey R. Wicklander Jeffrey R. Wicklander is offline
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Default Re: Flickering CFL

Quote:
Originally Posted by jkogel View Post
Does anyone have an answer to the original question?
It sounds like one of the switches is actually on, bad or loose bulb, but switch is in the down position because it's a 3-way circuit.

John Kogel
www.allsafehome.ca
Need to hear back from the OP. If John confirms that one of the switches is illuminated, THAT is the problem. The client seems to be sure that it is not a dimmer (even a toggle type dimmer).



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  #19  
Old 12/3/08, 10:34 AM
Frank P. Newman Frank P. Newman is offline
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Default Re: Flickering CFL

Quote:
Originally Posted by relliott View Post
Paul is right in changing the bulb first as it could be many things.
Rather than investing in another lamp, I would suggest moving it to another location in the home to see if the problem moves with it.



Frank P. Newman
Emerald City Inspections, LLC
Dublin, GA
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  #20  
Old 12/3/08, 3:35 PM
John Allingham John Allingham is offline
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Default Re: Flickering CFL

Quote:
Originally Posted by jwicklander View Post
Need to hear back from the OP. If John confirms that one of the switches is illuminated, THAT is the problem. The client seems to be sure that it is not a dimmer (even a toggle type dimmer).
I'll try to find out.
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  #21  
Old 12/3/08, 4:19 PM
John Allingham John Allingham is offline
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Default Re: Flickering CFL

From another board
http://www.hawthornevillager.com/php...b24fcd773790b0

Seems like it's not all that uncommon. Still no reasonable explanation that I've heard.
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  #22  
Old 12/3/08, 9:41 PM
brian winkle brian winkle is offline
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Default Re: Flickering CFL

Quote:
Originally Posted by jallingham View Post
From another board
http://www.hawthornevillager.com/php...b24fcd773790b0

Seems like it's not all that uncommon. Still no reasonable explanation that I've heard.
Jeffrey's explanation is reasonable. An illuminated switch gets its neutral thru the lamp filament, and will cause intermittent firing in some CFLs as it tries to complete it's circuit thru the CFLs ballast. Also, timer switches and X 10 switches that do not require a neutral in the switch box to operate can do the same thing.

Illuminated switches will also cause a voltage reading on a switched receptacle when it is off. In this case, the illuminated switch will not illuminate until a lamp is plugged into the receptacle and switched on.
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  #23  
Old 12/3/08, 9:47 PM
brian winkle brian winkle is offline
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Default Re: Flickering CFL

Here is a link explaining it better than I could: http://www.willnicholes.com/cflswitches.htm
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  #24  
Old 12/3/08, 9:56 PM
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Default Re: Flickering CFL

Quote:
Originally Posted by brian winkle View Post
Here is a link explaining it better than I could: http://www.willnicholes.com/cflswitches.htm
Makes sense, since CFL can light with static electricity or a high frequency tesla coil.
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  #25  
Old 12/4/08, 11:48 AM
John Allingham John Allingham is offline
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Default Re: Flickering CFL

Quote:
Originally Posted by brian winkle View Post
Here is a link explaining it better than I could: http://www.willnicholes.com/cflswitches.htm
I've been trying to open this link all morning without success. Is anyone else having a problem?
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  #26  
Old 12/4/08, 12:16 PM
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Jeffrey R. Wicklander Jeffrey R. Wicklander is offline
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Default Re: Flickering CFL

It's a no go for me, also.

Jeff



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  #27  
Old 12/4/08, 12:17 PM
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Default Re: Flickering CFL

Quote:
Originally Posted by jkogel View Post
Does anyone have an answer to the original question?
It sounds like one of the switches is actually on, bad or loose bulb, but switch is in the down position because it's a 3-way circuit.

John Kogel
www.allsafehome.ca
John there can never be a direct answer, as all of the posters could be correct.
It needs to be examined in person.
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  #28  
Old 12/4/08, 12:20 PM
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Michael Larson Michael Larson is offline
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Default Re: Flickering CFL

from Google cache

Compact Fluorescent Light Bulbs (CFLs) vs Illuminated Light Switches

The Problem

Recently I discovered an interesting fact about illuminated (lighted) light switches: they don't work very well with the new Compact Fluorescent (aka CFL) light bulbs.
There were a handful of light switches in my house that were hard to find in the dark, so I decided to replace them with illuminated switches. Once they were installed, however, the light bulbs they controlled would dimly flicker, even when the switch was "off."
At first I assumed the light switch must be defective: since the light was flickering, that must mean the switch is allowing current to reach it, even though it's in the "off" position. At that point I remembered something interesting about illuminated switches that I had forgotten: by design they're always passing current through, whether they're on or off.
This may seem odd, but it's logical when you consider that in order for the switch to light up, it needs a circuit to pass through it.
Here's an illustration of how a normal (non-illuminated) light switch works:

The black line with the yellow border represents the "hot" line, which feeds into the light switch. When the switch is "off", the current stops there, and the black wire leading to the light fixture is not connected to the current.

When the light switch is on, then the current continues through the switch to the light fixture (the current is represented by the yellow border), through the light bulb (lighting it) and through the white ("neutral") wire leading back to the circuit breaker.
A lighted (illuminated) switch behaves the same way when it is in the "on" position:

However, when it's in the "off" position, the illuminated switch does something that may seem odd: instead of cutting the current to the light fixture, it simply reduces the current, so that its internal light (typically an LED or, in the case of older models, a neon bulb) can use the current passed through:

Without this current passing through, the illuminated switch would not be able to illuminate.
Since the current to the light fixture is significantly reduced when the switch is "off," a normal incandescent bulb will not light. However, there is current passing through the bulb. To prove this, you can unscrew the bulb and see whether the illuminated switch stays illuminated. If it's wired as shown above (and most are), removing the light bulb will cause the switch itself to go dark.
Even though there's not enough current passing through to light an incandescent bulb, many compact fluorescent lights are sensitive enough to small amounts of current that they will flicker on and off, or even maintain a constant dim glow, when the lighted switch is "off."
The above illustrations show the wiring for regular "on/off" illuminated switches, but the same principles apply to three-way switches and four-way switches. In fact, if more than one illuminated switch is attached to the light fixture, the problem may be even worse.
What to do

In most cases, you simply have to choose which is more important to you: the compact fluorescent, or the illuminated switch. In my case, I decided to replace the flickering CFL with a regular (incandescent) bulb.
Another option is to keep the CFL(s), but replace the illuminated switch(es) with regular switches. This is the more energy-efficient option, and there are glow-in-the-dark faceplates you can buy which will absorb light during the daytime and release it in the dark. These faceplates work best when lots of light is normally available to them which they can absorb.
A third option is to install a switch with a pilot light. A pilot light works on a different principle from an illuminated switch, and the current to the light fixture is always either entirely on or entirely off.

However, this option is only available to you if both the hot (black) and neutral (white) wires are accessible in the switch box. Many light switches only contain the hot wire, so a pilot light switch is not always feasible. Pictured above and below are two pilot light switches I installed in my house in the summer of 2006.



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  #29  
Old 12/4/08, 12:58 PM
John Allingham John Allingham is offline
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Default Re: Flickering CFL

Thanks Michael. I wanted to send the link to my client but I don't think he would understand your text without the pics. Hopefully the link will re-activate somehow.
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  #30  
Old 12/4/08, 1:10 PM
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Michael Larson Michael Larson is offline
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Default Re: Flickering CFL

Quote:
Originally Posted by jallingham View Post
Thanks Michael. I wanted to send the link to my client but I don't think he would understand your text without the pics. Hopefully the link will re-activate somehow.
Found one of the pics.
Attached Thumbnails
flickering-cfl-pilot-light.jpg  



As a Professional Home Inspector, I support the privacy of my clients.

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www.MinnesotaHomeInspector.biz

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Services provided in East MN and West WI

Call me

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