I have a room I can enter from two different doors. Each has a rocker
type switch on the wall. The lights are flouresant tubes. Suddenly
one of the switches needed to always be in the down position in order
for the lights to have a chance of going on while using the other
switch. If this particular switch was not in the down position, then
the lights would always be off no matter what I do to the other
switch. I went to Home Depot and changed out both switches. It
fixed the problem completely for about 2-3 days.. Suddenly the same
problem is occurring again (now with the new rocker 3-way switches).
How could this be? Anyone have any idea what is going on here and
how to fix this problem?
Thanks a bunch for the help!
So you mean that possibly a wire is not tightly screwed down on the
switch properly? Or at the "fixture" between the switches? What
"fixture" would that be? Is there a fixture device which allows for
3-way switching? Do I need to find something ? Or are you speaking
of the lighting balast?
I would think if there were a loose wire at the fixture, the light
would be intermittent or not work regardless of switch position.
The wires that go only between the two 3-way swtiches are called
"travelers". One of them could be lose at either end, and there could
be splice somewhere in the middle, in a box.
Again I ask, how did you know which switch was bad? Because that is
the one at the top of the stairs that you usually use? Hmmm. Irrc,
you replaced both. So maybe it wasn't a switch..
The wire does not always go from one switch directly to the other. The
light can be in between and when this is the case the traveller wires are
connected together at the light. There could be a loose connection there.
What about the other switch B? Didn't it have to be in a particular
position also? Because if switch A stays in one position, only one of
the two positions for B will be "on". How did you know which switch
was the problem?
For a properly installed three way system to work, you need a three wire
cable to go from one switch to the other. sometimes this cable doesn't go
directly from switch box to switch box, but instead, goes from each
switchbox to the junction box that the light fixture is attached to, and
splices are made there. If your system did indeed work properly after you
installed new switches, but not now, you have a loose connection somewhere.
It could be at either of the switches, or in a wire nutted connection in
either of the switch boxes or in the lighting outlet box as Frank ketchum
Assuming the most common arrangement,
The way the switchs work is something like this:
Where the < and > are switches, and the
=== is a pair of travellers between the switches.
Normally, power comes in from the left, and switch
< sends it to either the top or bottom traveller,
and switch > either collects it from the same
traveller and sends it on to the light *.
From your description, one of the travellers
has either come loose at one end or the other,
or has an intermittent break in it, or one
of the switches is failing to make contact in
either the up or the down position.
If the light comes on with both
find a combination of position that makes
the light come on. Then flip both switches
once. The light should come on in that position
also. Since it doesn't, try rattling the
switch levers side to side. If the light
comes on, or the switch spits a spark,
then that's a bad switch.
If you get no results, take both switches apart,
after noting what wires go where, and check
each traveler for continuity. If you don't
have continuity, pray that there's a junction
box or something between the switches where
it's come apart. If you do have continuity,
replace both switches.
Sometimes an installer will cut a wire too short and will pigtail it to make
an extension of a wire. Look in the box for an extra wire nut which joins
two pieces together to make a longer one. It's a stretch that this is the
problem but hey, can't hurt to look.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.