The answer to 'ductwork blowing hot air' is that the most common causes are a problem with the HVAC system, leaks in the ductwork, or improper insulation. Symptoms include uneven heating, high energy bills, and rooms that are too hot or cold. Solutions may include sealing ductwork leaks, improving insulation, or repairing or replacing the HVAC system.
For minor issues like small duct leaks, homeowners may be able to perform some basic DIY repairs. However, for more complex problems or anything involving the HVAC system itself, it's best to call in a professional HVAC technician who can properly diagnose and fix the issue.