I have a box with two 2-wire switches, I need too change one of them to a 3 way. Is there a way to run a three wire cable from the attic above without damaging the wall around the switch. I suppose it is a no-no to use a common neutral for the short wall distance to get an effective five wires from the existing four. Tom Spang
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>>>Is there a way to run a
>>>Is there a way to run a three wire cable from the attic above without damaging the wall around the switch.
Is it a plastic box or metal?
Romex, BX, Greenfield ?
Age of home?
>>>but if you're living right
>>>but if you're living right you can fish into an existing box.
Hahaha..... that explains why I've never been able to!!!!!
Always had to settle for the box-ectomy procedure.
If it's an interior wall, running a new wire isn't usually as difficult as you perceive.
Otherwise, there are electronic switches available that can "extend" a circuit either wirelessly or on a limited number of wires.
3-way switch in existing
Thanks for your advice. I am not an electrician,but am an electrical engineer and have done a fair amount of wiring. Unfortunately, your right on with my thinking. Just a tough job.
Tom
I'm an EE as well, and have done my share of 'fishing" wires over the years (not as a pro, but as a homeowner & volunteer).
So long as there's halfway decent headroom above and no fireblocks in the wall you can fish in a new wire fairly easily. (However, it is still probably advised to banish small children and any others with sensitive ears from the job site.) It helps if you have a person on each end, but it can be done solo.
There was a article about small metal piece on a string and magnet rod from the box. Also, fishing is easier with fiberglass rod although they cost more. Hope it helps.