Blend Door or Blend Motor or Servo?

[Ilya]

On my Discovery II 2000 heater or ac to blow hot or cold air even when AC or Heater is off. From what I understand it is blend door,motor or servo that is responsible.
So what is the right name for the part? or parts?

Where I can get it?

Thank you

[Colorado Rover]

Ilya- I had same problem and it repeated itself 30 days later. If what you describe is the same you need the belder motor. I believe it is the motor and door are one unit. THis is a fun job too.