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7- Defrosting
1. Defrosting conditions under heating mode:
When heating, the cumulative running time of the compressor ≥45min (parameter 11)
, and the continuous running time of the compressor ≥5min;
Cooling coil temperature <-3°C (parameter 12);
① (ambient temperature - cooling coil temperature) ≥ 5°C (parameter 15), and -7 °C
≤ ambient temperature ≤ 17°C (parameter 16) for 30 seconds;
② (ambient temperature - cooling coil temperature) ≥ 9°C (parameter 15 + 4°C), and a
mbient temperature < -7°C for 30 seconds;
When the above conditions are all met, it will enter defrosting; (Note: ① and ② only n
eed to meet one of them)
When the temperature of the cooling coil is faulty, and the ambient temperature is ≤
20°C, the defrosting will be timed, and the defrosting time is every 10 mins;
2. Defrosting conditions at startup:
When the stop/standby/compressor cut off time ≥30min;
-7°C ≤ ambient temperature ≤ 3°C, and coil temperature <-3°C (parameter 12);
When the compressor starting condition is met (the water temperature is lower than
the backlash/starting temperature, but still not started), and the above conditions ar
e met, it will enter defrosting; .
3. Defrost operation frequency: When entering defrost, the frequency is fixed at 60Hz.
4. Condition for exit the defrosting:
After 2 minutes of defrosting, when the cooling coil temperature is ≥20°C (parameter
14) or the defrosting time reaches 10 mins (parameter 13), it will exit the defrosting.
5 Defrosting steps:
When the defrosting conditions are met, following steps will start:
1) Compressor stops, and fan stops after 15 seconds;
2) The four-way valve is energized at 55 seconds;
3) The compressor restarts at 60S;
4) The water pump keeps running;
The following steps will be performed when the defrosting exit condition is satisfied:
1) Compressor and fan stop;
2) The four-way valve loses power at 55S;
3) The fan is turned on at 60S, and the compressor starts after 5 seconds to resume
normal heating running;
6 The abnormal exit of the defrosting:
1) When the error protection occurs during defrosting, the system immediately exits
the defrosting and stops running;
2) Low pressure protection is not detected during defrosting;
7 Coercive defrosting: When the cooling coil temperature is lower than the defrostin
g exit temperature, press and hold the “M” +
“
▼” buttons for 3 seconds to enter the coercive defrosting.
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