AC Radiator fan always on if key on?

[Eric]

Please advise if anyone knows why the ac fan at ac radiator near engine
is always on when key is on.

Is there a relay?

Sensor switch?

Any help appreciated.

Thank You.

 

[Ron Earp]

You might try providing some details of the type of GT40 you have an so on. Without that sort of knowledge there won't be much of a chance for folks to help you.

Ron

 

[Eric]

Yes you are correct.
More info:
It is a CAV gt after # 100.

Thank You.

 

[Huw Peplow]

Yep if key is on and the system charged the fan drawing air through the condensor will run as it is designed to cool the hot compressed coolant and should always run when the ac is on and the ignition on. If the ignition is switched on and off you should also hear the clunk of the electric clutch on the compressor .These in turn are controlled via a relay which is tripped by the pressure switch or thermostat in the system.The dryer houses the pressure switch and if the system is not charged(ie is not above a preset pressure which is greater than atmospheric pressure)no current crosses the pressure switch and the relay is not tripped:no fan no clutch.The thermostat is another cut off in the system measuring the cooled air temperature in the evapourater in the ac unit under the dash.if getting too cold and a risk of freezing it turns off the compressor and is an adjustable knob in my case under the dash. If your system is not charged you have a problem with one of the components mentioned .Just check the voltage accross the thermostat or the pressure switch,the problem will be easy to locate