Whether the rack holds suction (low-side) pressure against its active operating target. Suction that runs high past its delay starves case temperatures across the rack; suction that runs low past its delay wastes energy and stresses compressors. Persistent deviation from the controller setpoint is the signal — the high / low setpoints and delays are configuration inputs, and one metric covers both directions rather than one metric per direction.
The table below summarizes the alarms that fire directly from Rack Suction Pressure. Each row links to the full operational detail (trigger, preconditions, action plan, human role, escalation, prevention) in the SOPs catalog.
| Alarm | Description | Severity | Tier | AI executes? | Value drivers | SOP |
|---|---|---|---|---|---|---|
| High suction pressure sustained | The rack holds suction (low-side) pressure above its active operating target for longer than its delay. High suction raises evaporating temperature across the rack and starves case temperatures on every circuit it feeds. | High | Managed | Hybrid | Product loss prevention · Energy savings · Asset lifespan | Open SOP → |
| Low suction pressure sustained | The rack holds suction (low-side) pressure below its active operating target for longer than its delay. Persistent low suction wastes energy, can flag a starving or valve/charge issue, and stresses compressors over time. | Medium | Managed | Hybrid | Energy savings · Asset lifespan · Product loss prevention | Open SOP → |
| Suction setpoint deviation | Rack suction pressure persistently deviates from the active controller setpoint in either direction, so the rack is not holding the operating target it is commissioned to — a control-health signal distinct from a single high or low excursion. | Medium | Managed | Hybrid | Energy savings · Product loss prevention · Asset lifespan | Open SOP → |
The action plan for each alarm lives on its own SOP page in the SOPs catalog — with the diagnostic steps, human role, value drivers, escalation, and prevention specific to that alarm. The list below maps each alarm to its SOP.