A system for fault detection and diagnostics of equipment. The system may also be capable of disaggregation and/or virtual submetering of energy consumption by equipment, such as that of heating, ventilation and air conditioning, lighting, and so forth, in a building. Vibration and current sensors, along with one or more algorithms, may be utilized for fault detection and diagnostics of equipment. Models may be developed to aid in deducing energy consumption of individual components of equipment, and the like, for a building.