I was recently working on my ceiling fan wiring. I had the breaker off and I confirmed no power coming in. While I was preparing to twist the cap onto the black wire (I was touching the exposed copper), the electric heat in my house kicked on and I got a smallish shock.
The shock wasn't as significant as touching a live black wire; if I had to guess I'd say half as painful.
Is this an indicator of a problem in my house's wiring?