Common Faults and Their Prioritization in Small Commercial Buildings

This study documents faults that are commonly found in small commercial buildings based on a literature review and discussions with building commissioning experts. It also provides a list of prioritized faults based on an estimation of the prevalence, energy impact, and financial impact of each fault. A total of 39 faults were analyzed for this paper and classified by location, stage, and type. The technical complexity of detecting each type of fault based on typically available information was evaluated for each fault. The annual energy impact (AEI) and annual financial impact (AFI) of each fault were estimated based on available information. Based on these estimates, 20 top priority faults were identified. Seven out of the 20 top priority faults occur in vapor compression systems such as air-conditioning, heat pump, and refrigeration equipment. Nonstandard charging, condenser, and evaporator fouling are the most important faults for this type of equipment.