AA 3815 then UA 3755 at O'Hare
Hartford → Chicago → Denver
Timetable, Chicago time
20:15AA 3815 from Hartford at the gate
18:37UA 3755 to Denver leaves the gate
22 h 22 apart on the timetable, overnight
UA 3755 leaves 22 h 22 after AA 3815 arrives on the timetable: more than half a day, so not a connection we count.