When you turn your central air conditioner on and the outdoor unit does not come to life, these are some of the possible reasons:
- Your AC might not be getting power because of a defective breaker or a burned or disconnect wire
- AC contactor might be defective
- AC thermostat could be damaged
- AC transformer might be faulty
- Squirrels or other rodents sometimes chew through low voltage wires
- AC contactor wire might have burned off
If the AC circuit breaker fails when you turn your unit on, check:
- AC breaker could be weak
- AC compressor might be grounded
- AC condenser fan motor could be damaged
- AC contactor might be shot
If your AC unit makes a humming sound, but the fan does not run, check:
- AC fan motor might be defective
- There could be a burned wire
- AC capacitor could be faulty
If the unit fan on your AC runs but the compressor shows no signs of life, check:
- One of the compressor wires could be burned
- AC compressor might be defective or placed on overload protector
- AS start capacitor might be faulty
If the outdoor unit on your AC runs, but no fan turns on inside the house, check:
- Your AC blower motor might be defective
- AC capacitor could be broken
- AC evaporator coils could be dirty or overgrown with garden debris and need to be cleared
- AC filter might be blocked with dust, dirt, pet hair and other debris and need to be replaced
- One of the wires might have burned out
- AC fan center might not be working
If your AC is leaking water inside the house, these are things to check for:
- Your drain might be clogged up
- Evaporator coil pan is possibly rusted out
If ice is forming on lines at the AC condenser, check for:
- AC evaporator might be dirty and need thorough cleaning
- AC filter might be dirty and need to be replaced
- AC might be low on refrigerant
- AC blower motor or blower motor capacitor might need to be replaced
If your AC thermostat is not providing the temperature that you have set, check:
- Your AC thermostat might not be calibrated correctly
- Your AC thermostat might be defective and need to be replaced
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