Spent 4 hours tracking down a ghost voltage on a thermostat wire in my own house

I was swapping out a basic Honeywell thermostat for a smart one, and the thing kept showing no power even though the breaker was on. Turned out there was a stray voltage leak from a shared neutral in the junction box, something the old unit just ignored. 4 hours of meter work and cussing later, I found a loose wire nut in the attic that was barely touching. Has anyone else run into phantom voltage messing with their low voltage stuff?

2 comments

2 Comments

patricia_hayes15h ago

Had a buddy go through almost the same thing. He spent a whole weekend chasing a ghost signal on his doorbell transformer, finally found a corroded wire nut behind a light fixture in the basement. Drove him nuts because everything looked fine on the surface. Did you end up replacing all the wire nuts up there or just the one?

noahhall12h ago

Actually I think you might be mixing up a couple different issues there. A bad wire nut behind a fixture wouldn't really cause a ghost signal on a doorbell transformer since those are two completely separate circuits. The ghost signal is usually from voltage leaking through a shared neutral or a bad ground somewhere else in the house.