A central air conditioning system runs in cycles: the thermostat sends a request for cooling to the air conditioner’s control board, the board turns on the compressor to place refrigerant under pressure, and the refrigerant circulates to remove heat from indoors. The cycle concludes after the thermostat registers the AC has met the target temperature, causing the compressor to cycle down (although the blower fan may continue to run).
A standard cooling cycle lasts for 15 minutes or more. This is the minimum time necessary for all parts of the AC to put in the work to make a noticeable difference in the indoor temperature. On hotter days, the cycle will last longer.