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Two conductor low voltage wire running parallel to duct.

My wife and I just bought a new to us home in Georgia.

The home was built in the 1980s and has rigid duct work going from the air handler to the ducts on the first floor. There may be some flex in there somewhere to make it quieter a bit, but I'm not 100% about that.

What I do know is that some vents have a two conductor wire running to them. Its brown, twisted upon itself, currently has no voltage to it, and appears to be low voltage in nature. I know that HVAC typically runs at 24VAC, so my working theory is it went to something like that.

My question is what could it be? Its not running IN the ducts, just zip tied to the outside of them the whole length.

Re: Two conductor low voltage wire running parallel to duct.


What is that both ends? Rigid or flex ducts have not bearing on what the wire is used for. It may have nothing at all to do with HVAC, it could be old phone line wiring, it could be doorbell wire, it could be current, or old thermostat wiring, it could be house wide speaker wire. Something they used in homes of that era. Where you could have music in every room, or intercom.

Look to see what it at the ends of the wire. Did you attempt to measure DC voltagle? or only AC?


Handy Andy In Mt Airy NC

Re: Two conductor low voltage wire running parallel to duct.

I know its not phone wiring or doorbell wiring, that is all properly identified. I'll be there today with my meter and I'll check it, but the wires appear to dissapper somewhere inside the HVAC closet. I don't think it would be speaker wire, its a little too small for that.

I don't think intercom either, because that would be strange to have coming out of the floor. Thermostat is a possibility.

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