DL 514 then WN 840 at Phoenix
Boston → Phoenix → St Louis
Timetable, Phoenix time
21:53DL 514 from Boston at the gate
13:35WN 840 to St Louis leaves the gate
15 h 42 apart on the timetable, overnight
WN 840 leaves 15 h 42 after DL 514 arrives on the timetable: more than half a day, so not a connection we count.