If you turn off your furnace for the summer, the fan may or may not work depending on your HVAC (Heating, Ventilation, and Air Conditioning) system setup. HVAC systems can vary, but there are generally two types of fan settings: on and auto.
Auto Setting: If your fan is set to "Auto," it means the fan will only run when the AC or heating system is actively cooling or heating your home. If you turn off the furnace, the fan will not work for the AC since there's no heating or cooling function running.
On Setting: If your fan is set to "On," it will run continuously, regardless of whether the AC or heating system is actively running. In this case, even if you turn off the furnace, the fan will still work when the AC is turned on, circulating air throughout your home.
To clarify, the furnace is the heating component of your HVAC system. It doesn't affect the cooling function directly. The cooling function is handled by the AC unit, which usually includes a separate fan for moving cooled air throughout the house.
If you're unsure about the fan settings or the specific setup of your HVAC system, it's best to consult the user manual or contact a professional HVAC technician to guide you through the appropriate steps for your system.