Building Systems Operations & Maintenance Flashcards

Which of the following is an example of predictive maintenance rather than preventive maintenance?

Answer: Vibration analysis to detect bearing wear before failure

Predictive maintenance uses condition monitoring data to time interventions, while preventive maintenance follows fixed intervals.

For which type of asset is a run-to-failure strategy most appropriate?

Answer: Low-cost, noncritical items whose failure has minimal consequence

Run-to-failure suits inexpensive assets where failure does not threaten safety, operations, or major costs.

BAS trend logs show an AHU's heating and cooling valves both partially open at the same time. What does this most likely indicate?

Answer: A control sequence fault or leaking valve causing simultaneous heating and cooling

Unintended simultaneous heating and cooling wastes energy and usually means a control logic problem or valve leak-through.

What is the main goal of retro-commissioning an existing building?

Answer: Optimize existing systems to operate as efficiently as possible to meet current needs

Retro-commissioning applies a systematic process to existing buildings that were never commissioned in order to fix operational issues and reduce energy use.

What does the maintenance metric MTBF measure?

Answer: The average operating time between failures of a repairable asset

Mean time between failures indicates reliability, while MTTR measures repair time.

A CMMS report shows 60% of work orders are reactive. What planned-to-reactive ratio is commonly cited as a best-practice target?

Answer: About 80% planned and 20% reactive

World-class maintenance organizations aim for about 80% planned work to reduce costly emergency repairs.

Under the Clean Air Act, what credential must technicians hold to service equipment containing regulated refrigerants?

Answer: EPA Section 608 certification

EPA Section 608 certification is required for stationary refrigeration and air-conditioning service, while Section 609 applies to motor vehicle A/C.