New GE Line of Z-Wave Switches/Recepticals (127XX Series)

No way to know until you open it up and look at the actual wiring. There are at least 5, and probably more like 8, different ways to wire a 3 way. It all depends on exactly what is where.

In particular, these models need a neutral wire.

Screw Terminal installation; requires wiring connections for Line (Hot), Load, Neutral and Ground. Traveler wire required for multi pole installation

See also: