Instruksjonsbok Volvo A25D - A30D

Cooling System

7

11

6

9 8

4 1 2

9

4 5

10

3

Hydraulically powered cooling fan The cooling fan is hydraulically driven with variable speeds based on cooling demands. The fan is side- mounted and can be swung out for service. The system responds quickly to the cooling needs of the: • Engine • Retarder • Torque converter Primary and secondary circuit The cooling system is divided into primary and secondary cooling circuits. The primary circuit cools the engine and retarder, and also supplies air compressor and engine oil cooling, as well as circulat ing coolant through the cool- ant filter and cab heater. The secondary circuit includes the torque converter. Electronically controlled temperature An ECU receives input from two temperature sensors and continuously controls the speed of the cooling fan. With two cooling circuits and sensors, the system reacts quickly to cooling needs. The fan rotates at reduced speeds most of the time, consuming less power, reduc- ing fuel consumption and noise, leaving more power available for productive work.

1 -Coolant pump, primary circuit 2 -Coolant pump, secondary circuit 3 -Coolant filter 4 -Engine oil cooler 5 -Thermostat, secondary circuit

6 -Retarder cooler 7 -Converter cooler 8 -Compressor 9 -Thermostat, primary circuit 10 -Radiator 11 -Expansion tank

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