Central air conditioners coordinate several components, including the compressor, condenser and evaporator coils, to provide cool air. A problem with one of these components may leave the unit blowing air with no ability to cool it properly, according to Green Energy Efficient Homes.
An outdoor compressor unit must have adequate air circulation to perform its cooling function. A unit covered by a porch or deck, for instance, may require relocation to a more open space to give it better air flow.
In some cases the air conditioner's evaporator coils may freeze temporarily, preventing them from cooling the air even though the fan continues to blow. Turning the air conditioner off for an hour or so should thaw the coils and return their functionality. If the problem persists, the coils may need replacement.
Sometimes the outdoor air conditioning unit can lose power even though the indoor unit continues to receive electricity to run the blower. Owners may have to flip the breaker switch on the outdoor unit to restore power. If resetting the breaker switch does not resolve the issue, the owner also can try resetting the condenser's high-pressure cut-out switch.