Troubleshoot a Fedders air conditioning unit by checking for common issues such as dirty condenser coils, incorrectly set thermostats and defective fan motors. While examining these issues, look for more complex problems that require fixing.
If a Fedders air conditioning unit is not cold enough, check to see if air filters are clogged or the condenser coils are dirty. Open the grille on the air conditioner, and remove the air filter. Either clean or replace a clogged air filter and dirty condenser coils as needed. Confirm that the thermostat is set correctly and that the compressor is working properly.
If the air conditioner is noisy, the fan motor or blower motor might be defective. Both the fan motor and blower motor have bearings that can be noisy if they have worn out. If these bearings are failing, replace the motor. If the problem persists, check whether the fan blade has broken or is rubbing on the fan housing.
If a Fedders air conditioner compressor does not run, examine the temperature control thermostat and the thermistor. Use an ohmmeter to test these parts for continuity, and replace either of them if necessary. If the compressor runs erratically after pressing the selector switch buttons, replace the switch.