Chris wrote in news:ab1044fc-aaea-4934-9479-
:

Thanks for the quick reply to all of you - I'll start poking around.
We did do some work on the basement a while back (that's where the
wires run through), but I can't think if things started happening
around then or not (I think I would have noticed), however I could
imagine some of the work that was done may have messed with the
wires. I do think that my thermostat is on the same set of wires and
it appears to be working fine so I'll start working from the button to
the chime. Thanks!


I once had the same issue. They had run the DB wire between the
brickmolding and door frame. Either it was not a prehung door of the
brickmold was replaced at some point. No hole for wire in brickmold. just
pressed and squeezed around behind it. It shorted.

To verify you have a short, disco wires at DB button. Disco same colored
wires at DB. Put a circut tester on the two wire ends. You should get
nothing. If you get an on indicator, it's hunt for the short time.