10
Evaporator Fan
Fan speed is selected and maintained by the main control board regulating the
length and frequency of the 13.6 VDC pulse. Temperature can cause some fan
speed variation. Fan speed can vary +/- 5%, depending on the temperature, with
higher temperatures causing slightly higher speeds.
The evaporator fan has a 4-wire connection:
White Wire (DC Common)
The white wire is the DC common wire used for testing. During repairs, DC polarity
must be observed. Reversing the DC polarity causes a shorted motor and/or board.
Red Wire (Supply)
Each motor uses an internal electronic controller to operate the motor. Supply
voltage from the main control board remains at a constant 13.6 VDC.
Blue Wire (Feedback/RPM)
On previous Arctica models, the blue wire reported rpm (speed) information to the
main control board for speed control purposes.
On this model, the board does
not require or read any feedback information from the fan motor.
mabe CONFIDENTIAL AND PROPRIETARY INFORMATION-NOT FOR PUBLIC DISCLOSURE. January 2008