Airwell AWAU-YCZ218-H11, Service Manual

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Electrical Control Function
136 Electrical Control System
1. Electrical Control Function
1.1 Definition
T1:
Room Air Thermistor (RAT)
T2:
Indoor Coil Thermistor (ICT)
T2B:
Indoor Return Gas Thermistor (RGT)
T3:
Outdoor Coil Thermistor (OCT)
T4: Outdoor Air Thermistor (OAT)
T5:
Compressor Discharge Thermistor (CTT)
1.2 Main Protection
1.2.1 Three minutes delay at restart for compressor.
1.2.2 Temperature protection of compressor discharge
When the compressor discharge temp. is getting higher, the running frequency will be limited as below rules:
----If 102
℃
<T5<115
℃
, decrease the frequency to the lower level every 2 minutes till to F1.
---If T5>115
℃
for 10 seconds, the compressor will stop and restart till T5<90
℃
.
1.2.3 Sensor protection at open circuit and breaking disconnection.
1.2.4 Indoor fan delayed open function
When the unit starts up, the louver will be active immediately and the indoor fan will open 10s later.
If the unit runs in heating mode, the indoor fan will be also controlled by anti-cold wind function.
1.2.5 Fan speed is out of control(Excluding AWSI-HKD009-N11)
When indoor fan speed keeps too low for certain time, the unit will stop and the LED will display the failure.
1.2.6 Zero crossing detection error protection(only for AWSI-HKD009-N11)
If AC detects time interval is not correct for continuous 240s, the unit will stop and the LED will display the
failure. The correct zero crossing signal time interval should be between 6-13ms.
1.2.7 Inverter module protection
The Inverter module has a protection function about current, voltage and temperature. If these protections
happen, the corresponding code will display on indoor unit and the unit will stop working.
1.2.8 Compressor current limit protection
If the compressor current exceeds the current limit value for 10 seconds, the compressor frequency will be
limited as below table.
Cooling mode:
Current frequency
（
Hz
）
Current limit value
（
A
）
Frequency limit
COOL_F16 ICOOLLMT12 Decrease the frequency to COOL_F4 and run at COOL_F4 for
3 minutes.
After that, the frequency will be adjusted according to the
capacity demand and rise to the upper level every 3 minutes
(When the frequency>COOL_F4 via capacity demand).
COOL_F15 ICOOLLMT11
COOL_F14 ICOOLLMT10
COOL_F13 ICOOLLMT9
COOL_F12 ICOOLLMT8
COOL_F11 ICOOLLMT7
COOL_F10 ICOOLLMT6
COOL_F9 ICOOLLMT5
COOL_F8 ICOOLLMT4
COOL_F7 ICOOLLMT3