Additional cooling pack with fans to handle and peak shave fuel cell transients and high ambient temperatures

A work machine cooling system for cooling primary power source cooling fluid for a primary power source may include a primary power source cooling unit and a second power source cooling unit fluidly connected so that primary power source cooling fluid flows from the primary power source through the primary and secondary power source cooling units is discharged back to the primary power source. The work machine cooling system may further include a primary cooling fan disposed proximate the primary fuel cell cooling unit to discharge airflow onto the primary fuel cell cooling unit, and a secondary cooling fan disposed proximate the secondary fuel cell cooling unit to discharge airflow onto the secondary fuel cell cooling unit. The secondary cooling fan may be turned off until the primary cooling fluid temperature is greater than a transient event threshold temperature indicating the occurrence of a transient thermal event.