The answer to 'why is my air handler blowing hot air' is that there are several common causes, including a problem with the thermostat, a malfunctioning air handler, or an issue with the refrigerant levels. The air handler is responsible for circulating air through the HVAC system, and if it is blowing hot air instead of cool air, it typically indicates an underlying problem.
Some common symptoms include the air handler running continuously, the air not feeling as cool as it should, and high energy bills. Potential solutions include checking the thermostat settings, cleaning or replacing the air filter, and inspecting the air handler for any issues. However, if the problem persists, it's best to call in a professional HVAC technician to diagnose and repair the issue, as improper handling of refrigerant or other HVAC components can be dangerous for a homeowner to attempt.