Haier HR18D2VAR Service Manual page 37

4.6 CN7 — — discharging temp. sensor connector; the discharging temp. sensor connected
/disconnected failure: 30seconds later alarm; the failure can be resumable. When compressor is
running, if the discharging temp. >248℉, compressor will stop; if the discharging temp.<203℉
for 3 minutes, compressor will run.
4.7 XT——time shorted function; twin-core pin; if it is with a jumper after being electirfied, the PCB
MCU time will be shorted;
4.8 CN8——pressure control port, can collect the signal.
If the pressure switch acts before the units start, the system will alarm immidately.
If the pressure switch hasn't acts before the units start, the system will alarm only when the
switch acts 3 times within 30 minutes, the failure can not be resumable. Please reset the power
to clear the alarm
4.9 CT——current value detected by current mutual inductor: after compressor is running, the
running current will be detected, if it is over current protection value (depended by the dip switch
setting) for continueous 20s, the unit will stop; 3 minutes later, it will resume to work. If it alarms
for 3 times within 30 minutes, the failure can not be resumable. Please reset the power to clear
the alarm
37
Central Air Conditioning
Model: Heat Pump, HR13-D1