3.10 High pressure protection
When the input signal of pressure switch is high level:1, that shows there is no protection.
When the input signal of pressure switch is low level: 0 for 1 minute, that shows high pressure protection
works. At this time, compressor stops, outdoor will send the alarm signal. The alarm can be resumable. If
in 60 minutes, the failure occurs 3 times, the failure can be confirmed and send failure code to indoor.
Meanwhile, by controling the max. condensate temp. Tc (cooling) or TmAVE (heating), please confirm as
follow:
In nominal cooling/dry/heating mode, high pressure can be controlled by limiting the max. frequency.
3.11 Low pressure protection
(1) When compressor is running, if output signal of low pressure switch is low level: 0 for 1 minute
continously, compressor will stop,outdoor alarms.
The alarm can be resumable. If in 60 minutes, the
failure occurs 3 times, the failure can be confirmed and send failure code to indoor.
(2) When compressor no running, if output signal of low pressure switch is low level: 0 for 30 seconds
continously, alarm will occur.
·
When unit stops, the reason that system still checks the low pressure : in a long time stop, make
protection for the compressor on the condition of great refrigerant leakage.
·
The reason that low pressure switch action time is 30 seconds: when compressor stops, low pressure
does not change, so it will be shorter than the set time in operation.
(3) When compressor starts up, in 8 minutes, low pressure switch signal will be shielded.
(4) In defrosting, low pressure switch will be shielded.
(5) In oil return procedure, low pressure switch will be shielded.
(6) In the refrigerant discharging procedure after the oil return in cooling is over, low pressure switch will
be shielded.
In addition, the system will control low pressure through the evaporator temp. TE to realize the low
pressure protection function.
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in
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p.
Keep for 5 seconds, stop to alarm, after 3-minute standby, the
unit can restartup. In 3 minutes it occurs 3 times continously,
unit will stop to alarm and the failure can be resumed after being
electrified again.
Reduce FQY rapidly 2HZ/S
Reduce FQY rapidly 1HZ/S
Reduce FQY slowly 1HZ/10S
Remain FQY
Increase FQY slowly 1HZ/10S
70
℃
68
℃
66
℃
64
℃
62
℃
60
℃
-53-
Commercial Air Conditioner
Model: AU18
/22
2XFERA
AS072/092/122XVERA