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Controls
  Main Board: Front Cover
MAIN BOARD
The new Zoneline series uses a main board that contains the microprocessor.  It processes the 
information input from the User Interface (UI) or wall thermostat, the thermistors, and fan motors 
feedback.  It then activates the associated relays for the selected cycle.  The main board also has a DC 
power supply to provide the needed DC voltage to run the indoor and outdoor fan motors. 
Personality is programmed into the board at the time of manufacture.
Service main boards will have “dip” switches to allow it to be set-up for the proper Zoneline model it will 
be installed in.
User Interface (UI) 
12 pin
Red Aux Set 
Button
CDC / 
Motion 
Sensors
Remote 
Thermostat
RJ-45
Heater Personality
AC input
Indoor 
Thermistors