Well, figured I'd follow up.
I contacted the GC (who is a great customer believe it or not) and asked what his expectations were as the homewoner had initally contacted him. Obviously, if it was caused by something above and beyond what was originally done then the homeowner would be expecting a bill. That was relieving anyway.
It was not the breaker. There were wires touching in a single switch box where we had installed a 4-Way switch. This was found after the breaker was tested and proven to be okay.
I just don't get how that happens after 2 years? The analysis from the field is that movement and vibrations could have caused things to shift and move with time and eventually the wires contacted each other. That's what everyone says but I'm not sure I buy it. Its not as if the wires are just strung into the box with no support and no fastening.
The room had been painted however, there was no evidence that the switch had been removed and put back...I mean, why would it...really.
So anyway. There you have it. Another of the electrician's life's great mysteries...partially solved...as it were.
