A management system for building equipment includes several units. An instruction transmission unit transmits an instruction to at least one device. A response reception unit receives a response indicating that a state transition is made by the device in accordance with the instruction. A detection unit detects an abnormal condition in which the response is not received by the reception unit within a reference time period after transmission of the instruction. A storage unit stores the reference time period. A time measurement unit measures a length of time from when the instruction is transmitted to when the response is received. A mode setting unit sets an operating mode of the management system to a reference-time-period calculation mode. A calculation unit performs calculations to determine the reference time period based on a measurement result obtained by the measurement unit, and prompts the storage unit to store the determined reference time period.