Can I replace the heat actuator; getting no heat inside the car? A4 AUDI 2001 QU

Hello, First, make sure the engine is getting warm and check your coolant level. Then, check to ensure that the heater hoses running from the engine to the firewall are warm. You may have blockage in the heater core or heater hoses, air in the cooling system, or you could have an issue in the vehicle with the blend door actuator(s). Blend doors actuators turn the baffles inside the ducts to channel in the proper temperature of air. They let a mix of hot and cold air in according to your settings. Check the fuses for the blend doors, and make sure you hear the actuator for the blend door turning when you change the heat setting. If you do not hear the blend door adjusting, it has likely failed.