A neighbor in my (US) building just found out that his laundry room (and others in the building including mine) are wired incorrectly. When the original washer and dryer were replaced, the dryer stayed on the existing 240 V circuit while the washer (needs only 120 V) was wired…elsewhere. In his case it was "bridged to some kitchen outlets" (mine is on the same circuit as outlets in the living room, I had to flip the breakers to figure it out).
He has since been told that this is not up to code and is a dangerous fire hazard. I believe it but I don't understand why. I'm an asic designer, with no experience in residential or power electronics. If my washer draws too much current while my TV, cable box, and video games are all drawing from the same path, wouldn't the breaker flip long before a fire? Isn't that the point of a breaker?
The breaker for the laundry room is a double-wide 30 A breaker. The washer is now on a standard width 15 A breaker. What's the problem?