Xoutpost.com - 4 Zone Climate Question

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Section 08 Climate Control from the following location describes the system. The system is more sophisticated than I originally thought.
Index of /pdf/e70

Quote:

Originally Posted by bawareca (Post 1053038)

The rear AC is not a standalone unit, and i dont believe that the front can be set on cooling (AC ON) and rear on heat, or vice versa. You can have that with let's say 3rd row seats when there is a standalone HVAC unit in the trunk with separate heater core and evaporator.

^^^ This, with a slight correction.

There is only 1 Evaporator and 1 heater core so you can't have A/C in the back and Heat in the front or vice versa (just like you can't have the driver with the heater and the passenger with the A/C).

I think all the 3rd row seat has is a heating element which is electric. I don't think it has it's own evaporator.

Different temperature settings adjust the amount of air blown, not the temperature of the air.

+1. Basically the definition of a "zoned" HVAC system. Air quantity is adjusted, not temperature. The increase (or lack thereof) of conditioned air is what changes the temperature of the environment based on the selected setting. So, if back seat is calling for more air than front, the main fan speed will ramp up with no additional air exiting the front vents (i.e. sending it to the back).

Operation of OP systems sounds normal.