I had a solar tube light system install in my bath, which is nice but now I
have the problem that the vent fan
fan only turns on with the lights.
I climbed up into the attic space and there's 1/2 inch metal wraped romex
from the fan to a junction where it meets the light wires, from there a
single line goes down the wall .
I guess what I want to do is access the wires to the fan and run a separate
line down the wall but I cant access them at the junction since there are
copper pipes covering them. So that leaves the fan box itself, with the
power diabled, I can cut the romex from the fan and wire nut some 12/2 line
and feed it down the wall to a new 2 line switch.
Does this sound Ok
Is there an attachment that clamps on to the 1/2 metal caseing to the 12/2
romex. Should I just get some metal cased line instead? I was thinking the
plain line will be easier to pull through into the box than the metal cased
Install a relay switch. Phone wire or bell wire is a lot easier to
fish through existing openings than 12/2 NM. And solid state relays
aren't that expensive, and old 16 volt bell transformers are a dime a
dozen. And you can do neat things, such as add time delays, like a
10 minute turn-off delay, etc.
A transformer and relay? Good grief! He has access to the fan and
area above in the attic. What's so hard about doing it the straight
forward way he proposed? It's no big deal getting another romex down a
wall from above to the existing switch location, as opposed to bell
wire and a more complicated hack job.
Also, no need for 12/2 romex, 14 gauge is fine, unless you already have
12 gauge. And yes there is a cable clamp for romex that will fit an
extra knockout in the fan. Not sure what he means about cutting the
existing wire, as it sounds like it should just be done from inside the
fan box, where he can disconnect and cap the existing wire and install
the new run.
On 23 Jun 2006 01:32:45 -0700, firstname.lastname@example.org wrote:
What hack job?
Relay switches are becoming more and more prevalent.
If you think about it, all motion sensor lamps are
controlled internally by relay switches.
X-10 type systems use wireless relay switches.
Second, why tear up drywall or run unsightly surface
raceways, if you can fish low voltage wires through
I've seen entire buildings hard wired with relay switches.
New construction. It may sound ridiculous, but it makes
sense, if you think about it.
Yes and both of those systems are far more complex, expensive and
failure prone than a simple wall switch, which is all that's needed in
Who said anything about tearing up drywall or running unsightly
raceways? The OP said he went up in the attic and can access the
bath fan area from there. Now, how hard is it to drill a hole in the
top plate, drop a single cable down and put in a new wall switch?
It's simple, straightforward and the preferred method that's used by
everyone from electricians to homeowners every day.
Makes no sense for this simple bath fan switch. The OP already was on
the right track to a simple solution.
a guess: did this work properly before the wall switch was recently
replaced? if so rewire the switch on the wall correctly or replace it
with the proper switches first after you have your electrician check
the circuit and switch and ceiling device with his multimeter.
do we presume that the solar tube is not electrical?
John H. wrote:
Technically, it's a code violation to splice outside a junction box.
But it's not really that unsafe, considering all the K&T wiring in
existence with soldered and taped connections.
Fishing NM or armored cable down the wall may be a problem - then
again, maybe not.
Modern codes have required insulation in all walls, so how old is
Also, you could J in the fan housing, if there's an extra 1/2 inch
knockout. That would eliminate cutting the cable.
Romex (NM cable) is fine, but then again, it may be a local code
violation. The trouble with code violations is not avoiding the
building inspector (it's a bootleg install anyway), but avoiding any
possible insurance snags, should something go wrong later and
necessitate a claim. Insurance adjusters are assholes, and will look
for ANYTHING to cut payments.
I wasn't kidding about the relay switch. It's probably how I would do
it, just for the flexibility (no pun intended). But to run a regular
switch leg, I'd try to J inside the fan box, local codes permitting.
BTW: copper pipes obstructing access to an electrical J box is a Bozo
No-No. Bad, BAD plumber!!! :-)
In which case you'd prolly find you couldn't run the fan unless the
lights were ON.
Because, it sounds from what the OP says that the guy who recently
installed the solar tube light system just grabbed power for them off
the existing switched feed to the fan and told the OP to use what used
to be the fan switch to control 'em both. I could be wrong about that,
but it's probably the "way to bet".
I've equipped the fans in all our bathrooms with "wind up" 0-60 minute
timers so we can leave the fans running for a while after using the
john, without having to remember to go back and shut them off.
Timers like these:
So it is. The line isn't hot, it's swithed from the
A hot lead has to be grabbed from somewhere, if the fan is to run
completely independant of the light (whether the light is on or off).
And the switch leg probably J's inside the box that is obscured by the
"Dewerks" is "Screwed" spelled backwards.
You'll probably have to heat it from the hot wire to the light switch,
if you can gain enough slack in the line to install a junction box.
Usually you can't, and in this case, what I would do, is install
two junction boxes near each other, adding cable between them.
An alternative is replace the single switch box with a duplex box,
and you already have a hot lead there. Then use half a new Romex or
whatever, to run from the new switch back up to the fan. You can use
the other wire to send a hot back up to the fan box, for later use,
e.g., a new unit later on down the line that might need it.
If the wiring is in BX (flex conduit), then you may be able to fish
an extra wire up through it. This may be easier than grabbing a hot in
the attic, on the same circuit.
thanks for all the info, I'll take everything into consideration. I'm
thinking I'll just
go with my original plans. . I'm not an electrician but this job seems so
straight forward that I can handle it.
I think a timer is a good idea if you got a houseful of kids who will
forget to turn off the fan, I'm single and my family rarely comes over.
Separating the two lines and running a
new fan line down the wall seems the most straight forward way for me to go.
I'll get my neighbor
to help me get the line through the box.
Does anyone know a good text for the weekend DIY for electrical jobs? There
are some more upgrades I want to do, I'm doing the easiest first.
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