Front mounted AC Condenser Cooling Fans

Chris, read this thread

http://tinyurl.com/fantrinaryswitch

Your radiator fans now become your AC condenser fans, and you will need them controlled by both the radiator temp sensors and the AC system sensors.

Larry

This diagram may not be totally correct, but it gets you pointed in the right direction.

Larry,

So does that mean that the trinary switch will turn the fans off when I am going over 80MPH?

I just think that having the fans running at that speed all the time is not needed unless it is really hot outside. Am I wrong to think this?

I have an Alfa Romeo with AC and it seems to cycle the fans on and off when the AC is running.

Thanks,
Chris

Yes the trinary switch will cycle the fans based on condenser head pressure. The other contact in the switch will lock out the compressor if system pressure is too low or too high. I have mine wired the way Larry diagrammed except I do not use a manual over-ride.
Forest

quote:

So does that mean that the trinary switch will turn the fans off when I am going over 80MPH?

There is no speed related switch in this wiring diagram. The fans are controlled by both the trinary switch and the coolant temp switch. The fans will cycle automatically with these two switches (unless the manual over-ride switch is turned on).

John

quote:

I just think that having the fans running at that speed all the time is not needed unless it is really hot outside. Am I wrong to think this?

No, not at all. But AC systems and coolant systems are different puppies.

quote:

There is no speed related switch in this wiring diagram.

And I am not aware of ANY AC fan control device that is based on vehicle speed. It is just not the way it is done.

quote:

I have an Alfa Romeo with AC and it seems to cycle the fans on and off when the AC is running.

It likely does cycle the fans. And the trinary switch installed in your Pantera will do the same. When the freon system pressure shows the need for greater cooling of the freon in its pass through the condenser, it will close and in turn close the relay, thus providing power to the fan (s).

Larry

The fans work by A/C pressure so when the pressure is high the fans run to cool off the condenser this drops the A/C pressure in the lines. So if you driving at 80 mph the fans might not come on because you are keep the condenser cool at speed.

It kinda works like your coolant system. When the coolant gets hot the fans come on. If you are driving at 80 mph your fans might not come on because you’re keeping the coolant cool.