Bill wrote:
run the water for awhile before using it for cooking or drinking water.

So far as life expectancy, they use black pipe for fire sprinkler systems
and these seem to last. But no one is drinking from these pipes. And when
draining or testing these sprinkler systems, the water is nasty. I wouldn't
drink it.

Black pipe is also used in old hot water/radiator systems. In both cases
water is added and left in the system. I think disolved oxygen is a
major cause of rust - if so the available oxygen reacts and the process
ends because new water is not added.

I would replace with copper or maybe plastic, not galvanized.

bud--