Fault Detection and Diagnostics (FDD) is one of the highest-ROI investments a building owner can make. Studies consistently show that 15-30% of commercial building energy is wasted due to operational faults that go undetected.
Industry finding: The California Energy Commission's Commissioning Collaborative found that retro-commissioning (which includes FDD) delivers average savings of 15% with a median simple payback of 1.1 years — one of the strongest ROI profiles in building efficiency.
Common Building Faults
Most energy waste comes from a surprisingly short list of issues: - Simultaneous heating and cooling — the #1 energy waster in commercial buildings - Stuck or failed dampers — especially outdoor air dampers that freeze open in winter - Hunting control loops — sensors or controllers oscillating instead of reaching setpoint - Schedule drift — equipment running outside occupied hours - Sensor drift — temperature sensors reading 2-3°F off, causing overcooling or overheating
How EdiMono's FDD Works
EdiMono analyzes energy consumption patterns at the whole-building and system level to identify anomalies:
- Baseline behavior modeling — learns your building's normal operating patterns
- Rule-based detection — checks for known fault signatures (e.g., baseload spikes indicating schedule issues)
- Statistical anomaly detection — flags deviations from expected consumption
- Prioritized alerts — ranks faults by estimated energy impact
On rule-based vs. ML approaches: Rule-based FDD catches known faults reliably and the logic is auditable. ML-based anomaly detection catches unknown faults but requires more data. EdiMono combines both: deterministic rules for common faults, statistical models for novel anomalies.
Real Results
A 12-building portfolio in Montreal used EdiMono's FDD to identify: - 3 buildings with weekend HVAC schedules running 24/7 (8% savings) - 2 buildings with simultaneous heating/cooling (5% savings) - 1 building with a stuck economizer damper (3% savings)
Total portfolio savings: ~15% reduction in energy costs, payback in under 6 months.
Key Takeaway
Prioritize FDD alerts by dollar impact, not fault severity. A minor sensor drift in a large AHU may cost more than a critical alarm on a small exhaust fan. EdiMono sorts alerts by estimated annual savings so your team acts on the highest-value issues first.
Key Takeaway
You can't fix what you can't see. FDD turns invisible energy waste into actionable maintenance tasks.