A hybrid air and liquid coolant conditioning unit is provided for facilitating cooling of electronics rack(s) of a data center. The unit includes a first heat exchange assembly, including a liquid-to-liquid heat exchanger, a system coolant loop and a facility coolant loop, and a second heat exchange assembly, including an air-to-liquid heat exchanger, an air-moving device, and the facility coolant loop. The system coolant loop provides cooled system coolant to the electronics rack(s), and expels heat in the liquid-to-liquid heat exchanger from the electronics rack(s) to the facility coolant. The air-to-liquid heat exchanger extracts heat from the air of the data center and expels the heat to the facility coolant of the facility coolant loop. The facility coolant loop provides chilled facility coolant in parallel to the liquid-to-liquid heat exchanger and the air-to-liquid heat exchanger. In one implementation, the hybrid coolant conditioning unit includes a vapor-compression heat exchange assembly.