I have to install AC interconnected smoke detectors in an investment
home I own (county code) and am running into a bit of a problem.

Most interconnected require the units all be on the same wire, which
is simple enough for new construction, but trying to run one wire from
the attic to the basement in a house built in 1954 is a world of fun
beyond what I want to do or pay someone to do.

I found Kidde makes AC smoke detectors that are interconnected by
wireless. Does anyone have experience installing these? Do all units
have to be on the same circuit in order for the wireless
interconnectivity to work?