UA543097-5

The heat exchanger consists of an air inlet housing assembly, a fan assembly, a core assembly, two valve assemblies, and two inlet and outlet port assemblies.

The fan assembly provides airflow through the heat exchanger during ground operation and is powered by a motor which uses a 115-Vac, 3-phase, 400-Hz external power source. The fan assembly is mounted axially between the housing assembly and the core assembly in which heated hydraulic fluid circulates through the passages to extract heat from the hydraulic fluid. Heated hydraulic fluid is directed from the inlet ports through the core assembly and to the outlet ports. Cool air flows through the core assembly to remove heat from the hydraulic fluid. A valve is located in each of the outlet ports to allow the hydraulic fluid flow to bypass the core assembly in the event of a blocked passage or high-pressure drop. The valves are preset at a certain pressure differential level. During cold start up or whenever there is any blockage in the heat exchanger, there is an increased hydraulic fluid pressure drop. The valves open to allow hydraulic fluid flow directly to the outlet ports.