Is my AC not controlled by a breaker?
What do the switches that control the units look like? If there are two individual switches that feed power to the unit, it's possible that each switch is fed from two different 120 volt, single pole breakers. If this is the case, there also may be other loads, such as lights or receptacles, on each 120 volt circuit. This would be an unacceptable installation practice and would also be a violation of the National Electrical Code.