On Oct 16, 6:10*am, "Robert Green" wrote:
wrote in message

...



On Fri, 15 Oct 2010 15:58:05 -0400, "Robert Green"
wrote:

"Boothbay" wrote in message
....
I have a switch in bathroom that lights up my 25w florescent bulb. For
years I've used the up toggle switch to turn it on and down to turn it
off. Now, for the past week or so, its doing the reverse. It won't
turn on unless it turn it down. Is this possible? Its really
complicated to get at the switch cause its embedded into a large
medicine chest, and an old one at that...came with the house.

Sounds like the switch is failing - not unusual for cheaply made switches
in
corrosion-prone areas like a bathroom. *I predict it will work for a
while
longer and then fail, perhaps on, perhaps off, and maybe with a little
sputtering. *I find that clamp lamps with a rotating knob switch to fail
in
much the same way. *Heat, moisture and age are all factors.

It's not very likely to be a hidden three-way switch because it's in a
bathroom. *I don't think I've ever seen a three-way switch in a
bathroom -
ever. *Nor is it likely to be gremlins rotating it 180 degrees just to
mess
with you.

When you hear hoofbeats, think horses and not zebras. *The most likely
explanation is just typical cheap manufacturing coupled with a harsh
environment.
*I've seen LOTs of 3 way switches in bathrooms. Mostly in on-suites -
but any bathroom with 2 doors.

Well, I've never seen a bathroom with two doors, either. *No, wait, that's
not true. *Only in college dormitories with shared bathrooms - but that's
certainly not a typical residential environment. *(-:

It's still most likely to be a bad switch given its location (wet bathroom
on the side of the medicine cabinet) and the symptoms the OP described. *A
switch like that may not be well-sealed and after years of operation with
damp fingers crud may have made its way into the switch internals.

I'd be even more certain of a bad switch if the load was more than 25W - the
closer the switch is to something hot, the greater the chance for failure..
When I used to use 300W photofloods in the studio, the cheaper lamp holder
switches would fail with regularity - which is why I think it's a bad switch
from what the OP described. *Obviously the greater the current, the greater
the potential for corrosion and material failure.

I'll bet the "feel" of the switch has changed. *Whenever I've had a toggle
switch begin to enter a failure mode, the switch feels "sticky" or "mushy"
and doesn't have the right "snap" to it.

--
Bobby G.

"Well, I've never seen a bathroom with two doors, either. No,
wait, that's not true. Only in college dormitories with shared
bathrooms - but that's certainly not a typical residential
environment."

They are not all that uncommon.

Here are just a couple of the plans found via a Google search:

http://math.berkeley.edu/~whitney/ou...planbefore.gif
http://www.travelswithtrouble.com/pr..._sinks_v_3.jpg