I live in a 1903 house with a mixture of galvanized and copper plumbing. It is a single story house. The majority of the plumbing is located in the basement. There is a kitchen sink, refrigerator supply, bathroom sink, shower, and washing machine. Everything seems to operate normally.
Here is a procedure that makes something quite strange happen:
1) I shut off the inlet COLD water supply to the hot water tank
2) I open the HOT water side of the bathroom sink until the flow stops, and leave it turned on. It only takes a couple of seconds for the pressure to drop and the flow to stop.
3) I open the COLD water in the kitchen sink.
When I do this, the cold water coming from the kitchen sink is very low flow, but the bathroom sink starts flowing COLD water rapidly (I left the hot water valve turned on). How can this be?!