The most common central cooling system is a split system, which includes an outdoor cabinet containing a condenser coil and compressor, and an indoor evaporator coil, usually installed in conjunction with your furnace or air handler. The compressor pumps a chemical called refrigerant through the system.
Once warm air inside your home blows across the indoor evaporator coil, its heat energy transfers to the refrigerant inside the coil. That transfer, in turn, “cools” the air.
The refrigerant is pumped back to the compressor where the cycle begins again. The heat absorbed by the refrigerant is moved outside your home while cooled air is blown inside. Moisture that contributes to humidity is also condensed out of the air. Your cooling system is usually combined with your central heating system because they share the same ductwork for distributing conditioned air throughout your home.