Duovalve, function - GF83.20-P-2100-01S
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Function
The duovalves for the rear air conditioning are controlled by pauses directly from the rear air conditioning pushbutton control module and themselves control the coolant flow through the rear heater core separately for the right and left side. The closing and opening times per duovalve pause cycle depends on the deviation between the actual temperature and set temperature.
Control principle
The electromagnetic coils in the duovalves are actuated digitally by the rear air conditioning control module. In this manner, the quantity of hot water flowing through the rear heater core is regulated separately for the left and right sides. The duovalves are open (not actuated) when they are not under power.