Welcome to the Nissan Patrol forum. To post a question and to see less adds on the forum then you will have to register
first. We are an easy going friendly forum so join in the conversations and feel free to ask any questions.
Become a forum sponsor for only $20 and see no adds with faster page loading times and many extras benefits.
I didn’t study it too closely but I assume it shuts off progressively depending on the flap position. It would logically be fully closed when the flap is closed such that no air passes through the heater core. Halfway flap would probably be half flow hot coolant.
I’m happy I don’t have the tap so I don’t need to worry about reusing an old unit.