The fan is an important part of the overall operation of an outdoor air conditioning unit. The fan draws the hot air created by the compressor up and out of the unit so the coils can cool down the fluid running through them. If the fan stops running, the heat will build up in the unit and warm air will start to get blown into your house. There are a couple of things that can make the fan stop working. One reason is that the bearings on the motor have worn out and the fan can't spin around anymore. Many homeowners who like to work on things around the home can test the fan bearings and replace the motor by themselves.
Check for Power First
You need to know if the air conditioning unit is getting power or not. This is pretty easy to figure out. If you can hear the compressor humming, you know the unit is getting electricity. You can immediately start checking the bearings on the fan.
The easiest way to check the bearings is by turning the fan blades. Take a stick or a long screwdriver and poke it through the grates on the fan cover. Push the stick against the blades. If the blades don't spin around freely, or if they don't spin around at all, you know that the bearings have gone bad on the motor.
Remove Fan Motor
Shut off the power and unscrew the fan cover from the unit. Take the cover and turn it upside down. Disconnect the electrical connections going to the motor by pressing down on the tabs on the clips for the connections and pulling the wires off of the terminals on the fan motor.
The fan motor is attached to the underside of the grill with three or four bolts (depending on the type of unit you have). Remove the bolts and separate the fan and motor from the grill.
Take off Fan Blades
You need to remove the fan blades from the shaft on the motor. There is a set screw holding the fan to the shaft. Loosen the set screw and slide the fan blades off of the shaft.
Take the old motor with you to the air conditioner parts or hardware store. But an exact replica of the old fan that is rated the same for voltage and output. Slide the old fan blades onto the shaft of the new motor and tighten the set screw. Bolt the motor to the grill and attach the wire connectors. Screw the grill back onto the air conditioner unit and restore the power. The fan should spin around just fine now.
If these repairs sound too involved to you, contact an AC repair company like the one represented at http://calldoctorfixit.com.