ICE AIR ccHPWH Series, Руководство по установке и обслуживанию

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19
Main functions
Note: The following description is for reference only, please refer to the latest version of the program
for specific function parameters.
1. Defrosting
When the outdoor temperature in winter is below 32F (0°C) and the evaporator temperature is lower than the
dew point temperature of the ambient air, condensation will occur on the surface of evaporator. When the
ambient air temperature is below 32F (0
℃
), the condensation water will form a thin frost on the coil. Severe frost
will affect the heating effect of the machine, so the unit will enter defrost mode to melt the frost, then return to
normal operation.
The unit will determine whether it needs to enter the defrost based on the coil temperature, the ambient
temperature, the difference between the ambient temperature and the coil temperature, and the compressor
running time.
When the unit meets the conditions for entering the defrost cycle, the water pump keeps running and the
compressor stops. After 60s, the four-way reversing valve changes direction and the fan stops running. After
10s, the compressor restarts and the fan stop.
Exit the defrosting
：
Defrosting time ≥ 6min
；
Coil temperature
＞
60F (16
℃
)
；
Water tank temperature ≤ 43F (6
℃ ) and lasts 10s
；
As long as one of the above conditions is met, the defrosting will end.
If there are other compressors in the same group that are defrosting, and
The coil temperature
＞
64.5F (18
℃
);
There are no other units in the same group that are defrosting and the fin temperature
＞
60F (16 ℃ );
No alarms or faults;
The interval time for switching to heating after exiting defrost > 0.
As long as one of the above conditions are met, the defrosting will be exited.
When the unit meets the defrosting conditions, the fan will turn on again 5s before the compressor stopped, the
four-way valve will switch on after the compressor stopped for 60s, and the compressor will turn on again after
10s.
2. Antifreeze function
When the unit is in the standby state (powered ON but not responding to a demand for heat) or the unit is in the
starting state, but the water pump has not been turned on, it will judge whether the unit needs to enter the anti-
freezing function. Anti-freeze protection references the ambient temperature and the inlet water temperature
sensors. To protect the unit during low ambient conditions the unit is equipped with two modes of freeze
protection that utilize the water pump and compressors.
If either of the below conditions are present, the water pump mode will be enabled:
1.
Ambient temperature ≤ 36F (2.25
℃
) and water inlet temperature ≤ 60F (15.5
℃
)
2.
water inlet temperature ≤ 52F (11
℃
)