Nobu NBFS-48IDU Service Manual page 36

P7 light
PA light
PC light
low or high voltage
7
protection
The evaporator coil
10
high temp. protection
The outdoor ambient
11
high temp. protection
the sensor and the detection circuit are
abnormal.
1、Check whether the supply voltage is out of
rang from 150 to 270V
2、Check the voltage detection circuit of the IPM
base board is abnormal, if it is abnormal, the
IPM base board or the electric control board
should be replaced.
1、 Check whether the condenser of outdoor unit is
too dirty, and it should be cleaned when it is too
dirty.
2、
Check whether it is running at bad condition
long time.
3、
Check whether senor and wire are normal.
1、Check the outdoor ambient temperature is too
high or there is heat source around the outdoor
unit.
2、 Check whether the sensor and sensor wire are
normal.