What is an example of a fault that triggers a BAS alarm?

• A. A stuck damper or a compressor that fails to cycle as expected.
• B. A sensor reading out of range triggers alarm.
• C. A routine filter replacement.
• D. A user toggling the control panel.

Answer: (A)

A BAS alarm is triggered by a fault that prevents equipment from operating as intended. A stuck damper or a compressor that fails to cycle is a clear, tangible fault in critical equipment. When a damper sticks, airflow is not controlled as the system expects, and when a compressor doesn’t cycle, cooling or heating performance drops below setpoints. These faults create abnormal operating conditions, which the BAS detects and flags with an alarm so maintenance can intervene.

Maintenance actions like routine filter replacement aren’t faults in the system—they’re scheduled upkeep. A user toggling the control panel is an operator action, not a fault in the equipment or control logic. A sensor reading out of range can trigger alarms as well, but the example of a stuck damper or failing compressor directly illustrates a classic equipment fault causing abnormal operation and an alarm.