Evaluation of the performance of low-cost monitors for their use in fault detection and diagnosis

Fault Detection and Diagnosis (FDD) is a process that helps to identify anomalous behaviour caused by operational faults in HVAC systems. However, the lack of sufficiently spatial-granular sensor networks in buildings and their poor accuracy is hindering the widespread uptake of FDD tools. While installing additional Low-Cost Sensors (LCSs) and Low-Cost Monitors (LCMs) required for FDD could provide a viable solution, their performance needs to be evaluated and deemed adequate. The objective of this research is to test and rank multiple LCMs based on their suitability for use in FDD applications. The study was conducted in a controlled climate chamber to test multiple LCMs and evaluate their performance in measuring Temperature (T), Carbon dioxide (CO2), and Relative Humidity (RH) under varying conditions. Metrics corresponding to Precision, Linearity, Bias, and Error were calculated and a weighted rating based on the metrics’ values for each LCM was obtained using the rating scale
of the Smart Readiness Indicator (SRI) framework and the importance of the parameter for FDD. Based on the results, the top-performing monitors are recommended for installation to collect data for FDD applications.