Electrical Wiring in the Home/Low voltage on 3-way


I have a home repair business here in FL and have run across an issue I haven't figured out yet.
This home is built 2007, trying to install a ceiling fan on the lanai where there is a couple 3-way switches controlling a ceiling pancake box. I pulled the old fan that was working off the switches but it was only coming on with two of the three can lights out there. I've installed hundreds of fans and with this new one I need to install the supplied wall switch with built in control like the Hampton Bay remote switch but it needs to be on a single switch instead of the three ways. When I pulled the fan I have two each of  the normal red, black, white and a ground. Strange thing is whe I separated all the wires I have one red and one black that are constantly hot off one breaker instead of just the regular black wire. Thought there might be a faulty 3-way switch and they seem ok, it takes two separate breakers to kill the power to both 3-way switches. I killed the power and took everything loose and put my signal injector/tracer on it and found the one romex that has the traveler in it to the second switch. I can't  seem to get any tracking located to the ceiling box. On any of the legs on either switch. When I have the wiring disconnected at all three points I and pulling 120v on the black leg and 31v on the red. Checke the breakers and am getting good voltage at the box, looked all over for loose grounds and even a hidden dimmer that might be wired in by a previous owner.
I'm at a loss for what to try next other than running a new line over to the box on the wall where I have good power. I did check a 240v box on the lanai that is prewired for outside kitchen and I'm getting the same 120 & 31v on the unused wiring but not at the panel.

Almost always, if you get low voltage, it is because of a disconnected white neutral wire somewhere in the circuit. The reading you are getting is feedback through the light or fan.  If you have to turn off two breakers to turn off power to the same wire, the two circuits are mixed together somewhere.  That can be very hard to find. There are many combinations of wiring a 3 way switch.  If both switches have only 3 wires, then the power enters at the fan. If you have 2 cables connected to one switch, the 3 wire cable should contain the travelers, and the 2 wire cable should either be the power from the source, or the wire going to the fan.  Hopefully some of these observations will help you.
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Electrical Wiring in the Home

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Bob Sponaugle


Just about any home wiring question. (not appliance repair) I have done all kinds of home wiring for myself, including adding a new breaker box, etc. Please, questions from North America only. Please be specific with details.

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