No heat, where is the blend door actuator located and how to remove it?

To me it sounds like the heater core is clogged or you have an air bubble in the heater core. I would remove the heater hoses and flush the core using a garden hose and then refill the system. Next start the engine and let it get hot, do not install the radiator cap, raise the front of the car with a jack while the engine is running, and then lower the front and raise the rear of the car. You should see bubbles come out of the system.

Here is a video to help:

https://www.youtube.com/watch?v=SNRb6pSwYuU&t

I don't think the actuator can cause this problem, but you never know here is the location of the temperature actuator (air mix door) so you can check it out. Check out the images (below). Please upload pictures or videos in your response of any problems so we can see what to help you with.