ASHRAE Controls Automation and Building Systems Integration Flashcards
6 cards from real ASHRAE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 ASHRAE Controls Automation and Building Systems Integration flashcards as text
What is 'fault detection and diagnostics (FDD)' in ASHRAE building automation context?
Answer: Automated monitoring algorithms that detect abnormal equipment operation and identify likely fault causes to support maintenance decisions
FDD uses sensor data and model-based or rule-based algorithms to automatically detect when equipment is performing abnormally and diagnose the probable cause, reducing energy waste and improving reliability.
According to ASHRAE guidelines, what is 'commissioning' of building control systems?
Answer: A quality assurance process that verifies all HVAC and control systems are installed, calibrated, and operating in accordance with the owner's project requirements
Commissioning is a systematic process to verify and document that building systems perform interactively according to the documented design intent and the owner's operational needs.
In ASHRAE-compliant building controls, what is the function of an 'air handling unit (AHU) mixed air temperature sensor'?
Answer: To measure the blended temperature of return and outdoor air to enable economizer control and prevent coil freezing
The mixed air temperature sensor measures the temperature of blended return and outdoor air, which is used by the economizer controller and to verify minimum outdoor air fractions and protect heating coils from freezing.
What does ASHRAE mean by 'interoperability' in the context of BACnet and building automation?
Answer: The ability of devices from different manufacturers to exchange data and work together in a single integrated control system
Interoperability means that BACnet-compliant devices from different vendors can share data and coordinate functions over a common network without requiring proprietary gateways or custom programming.
In ASHRAE control sequences, what is a 'minimum position' for an outdoor air damper?
Answer: The smallest damper opening maintained at all times during occupied hours to ensure minimum code-required ventilation airflow
The minimum outdoor air damper position is set to ensure the AHU delivers at least the minimum outdoor airflow required by ASHRAE 62.1 during all occupied periods, regardless of economizer or load conditions.
According to ASHRAE energy codes and guidelines, what is 'supply air temperature (SAT) reset' designed to reduce?
Answer: Simultaneous heating and cooling energy waste by raising the cooling supply air temperature when zone heating demand is low
SAT reset raises the supply air temperature setpoint during low-load or mild weather conditions, reducing reheat energy in VAV systems where terminal units would otherwise reheat excessively cold supply air.