Air Conditioner Service Manual
10
4) Under emergency operation, the function of compressor’s time-delay protection, Anti-frosting
protection in cooling mode, Overheating protection in heating mode, sensor fault protection and
defrost operate are effective.
5) Under emergency operation, once effective signal from remote controller received, the A/C
exits form of emergency mode without delay, and operates according to the setting value from remote
controller immediately.
9. Auto-restart function
1) The PCB retains the setting parameters in case of power off. When the power supply is resumed,
the machine, which has been started up the power-off memory function, is able to restore into the
original running state automatically.
To press the emergency button and power on the unit, and hold on for10 seconds, The buzzer
2) will
ring
three times
, after this operation, the auto restart function activated.
3) To close auto restart function while it is activated, repeat process as above 2), the buzzer will ring
four times.
10. Protection / Failure code
10.1 Protection
1) Compressor’s protection:
a. The PCB which with Auto-restart function, once it is activated, the compressor goes along 3min
delay protection when power on, otherwise the compressor without this protection even when the PCB
is power-on.
b . The compressor’s 3 min interval protection: the compressor can’t start-up until it stops 3 min later.
(
except for the defrosting process
).
c.
．
After the compressor started, it’s operation state remains the same within 3 min even when ST, RT
variation.
2) Anti-frosting protection of indoor evaporator (Cooling mode):
If IPT
≤
0°C detected in consecutive 3 min, compressor and outdoor fan motor to be stopped operation,
indoor fan motor runs at high-speed forcibly; if IPT
≥
5°C detected 3min later, then outdoor fan motor
and compressor will start up, and indoor fan motor restores to it’s original state.
3) Overheating protection (Heating mode):
If IPT
≥
55°C, the outdoor fan motor: OFF.
If IPT
≥
65°C, the compressor: OFF, and indoor fan motor runs at high-speed forcibly.
When IPT
≤
48°C, the outdoor fan motor and the compressor start up, indoor fan motor restores to it’s
original state.
4) Cold air prevention (Heating mode):
This function is intend to prevent cold air from being discharged when the heating operation starts or
when defrosting.
a. When running into the heating mode, once the compressor fails to comply with the start-up
conditions, the fan speed is regulated according to the coil temperature within 2 min, 2 min later the
indoor fan motor stops. If the compressor starts up within 2 min, then operating according to Figure 5.
Under heating process, while the compressor stop (including stopping for protection), the fan motor’s
operation (including stopping the indoor fan motor) is regulated according to the coil temperature
within 1min, 1min later the fan will be stopped forcibly.
