I'm using a radiator and condensing radiator with two fans from a MK1 1.6 Focus. One fan has just a pair of wires going to the motor so it's single speed. The other has four wires so I'm guessing two speed. Basic question, which fan is for the coolant and which for the aircon?

Thank you

John

The 2 speed fan is for the engine and operates at the lower speed when just dealing with idle over temperature, and uses the higher speed where the engine is under load to deal with the larger heat output of the engine in that state.

The a/c fan operates according to system pressure when the a/c is on, usually using a triple (trinary) switch to: protect against no-gas operation, activate the compressor, and operate the fan.


Dave

quote:

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Originally posted by obfripper
The 2 speed fan is for the engine and operates at the lower speed when just dealing with idle over temperature, and uses the higher speed where the engine is under load to deal with the larger heat output of the engine in that state.

The a/c fan operates according to system pressure when the a/c is on, usually using a triple (trinary) switch to: protect against no-gas operation, activate the compressor, and operate the fan.


Dave

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