Your HVAC system has burners on it that produce combustion gases to provide warm air.
Even though a portion of your split HVAC system is located outside your home, it does not use your outdoor air to cool and heat your home. Typically, an HVAC system is designed with a cooling unit designed to produce cool air and a heating unit that produces warm air. The air conditioning unit, which comprises a compressor and a condenser coil, is usually installed outside your home. In contrast, the evaporator coil connected to your furnace is installed inside your home. To keep your entire home cool in summer, the indoor evaporator on your HVAC unit will transfer heat energy to the coils. These coils are packed with refrigerant, which cools the air. The refrigerant will then flow through tubing to the outside compressor, restarting the cooling process. During the cooling process, heat from your indoor space is absorbed by the refrigerant, which then takes it out to the condenser coil to be blown outside the home. Your HVAC system has burners on it that produce combustion gases to provide warm air. These gases flow through to the heat exchanger. As the gas flow through the heat exchanger, it is warmed and sent through the duct system throughout the various parts of your home. Even in warmer seasons, when your household requires cool air, your heating system will work jointly with your air conditioning system to provide cool air throughout your home. The circulating fan attached to your air conditioning unit is a shared component between your heating and cooling systems that ensures proper air circulation in your home.