Precision cooling units (from Vertiv/Liebert, Stulz, Schneider and others) expose SNMP for supply/return temperature, humidity and unit status.
Most modern CRAC/CRAH units have a network card or built-in controller (often called something like a "monitoring card" or "iCOM" module depending on vendor) separate from the unit's mechanical controls.
Configuration follows the same general pattern as UPS and PDU network cards: enable the agent, set a non-default community string, and note the OID set the vendor documents for supply temp, return temp and unit fault status.
Alert on unit fault/alarm status as critical, and on supply-temperature drift as a leading indicator; a cooling unit trending warmer over hours, well before it trips an alarm, is often the more useful signal.