SAM4 detects loose belt on a critical HVAC system

Honeywell installed SAM4 on a critical HVAC system at its facility in Delft, the Netherlands to detect upcoming failures at an early stage so that maintenance can be performed before breakdowns occur. Because the HVAC system was housed in a remote location, installing vibration sensors was impossible. Honeywell decided to use SAM4, Semiotic Labs’ online condition monitoring solution that analyzes electrical waveforms to detect machine failures. SAM4 installs its sensors inside the motor control cabinet and not on the asset in the field, enabling condition monitoring for assets operating in hard-to-reach places.


SAM4's sensors and communication devices were installed inside the HVAC system's motor control cabinet. The SAM4 gateway then connected to the SAM4 platform over 4G. After 60 minutes, the system was up and running and started collecting data. After a training period of 3 weeks, SAM4 began providing insights into the HVAC system's condition, performance and energy consumption.


After a few months of monitoring, SAM4 detected a loose belt and sent an alarm, triggering an inspection. SAM4's findings were substantiated, and Honeywell replaced the belt, preventing unplanned downtime.

Zooming in on the data

1. SAM4 generated an alarm for an increase in energy at the rotational frequency, which is often associated with a loose belt.
2. Upon inspection, a loose and dry belt was detected. In the absence of replacement parts, the belt was tightened, resulting in a reduction of scores for that specific failure mode.
3. After replacing the aging belt with a new one, scores leveled out at the pre-issue level.