Gree GWHD24NK3FO Service Manual page 28

Service Manual
1.3.3 Outdoor fan control in heating mode
The outdoor fan starts before 5s of the starting of compressor and then it will run in high speed for 40s;
The fan shall run at every speed for at least 80s;
When the compressor stops, the outdoor fan stops after 1min.
1.3.4 Defrosting function
When the defrosting condition is met, the compressor stops; the electronic expansion valve of all indoor units open in big angle;
the outdoor fan stops after 40s of the stop of compressor, meanwhile, the 4-way valve reverses the direction; after the 4-way
valve reverses the direction, the compressor starts; then begin to calculate the time of defrosting, the frequency of the
compressor rises to reach the defrosting frequency.
1.3.5 Oil-returned control in heating mode
1.3.5.1 Oil-returned condition
The whole unit is operating in low frequency for a long time
1.3.5.2 Oil-returned process in heating mode
The indoor unit displays "H1"
1.3.5.3 Oil-returned finished condition in heating mode
The duration reaches 5min
1.4 Fan Mode
The compressor, the outdoor fan and the 4-way valve are closed; temperature setting range is 16 30 .
2. Protection Function
2.1 Mode Conflict Protection of indoor unit
When the setting mode is different of different indoor unit, the unit runs in below status:
a. The mode of the first operating indoor unit is the basic mode, then compare the mode of the other indoor units to see if there
is a conflict. Cooling mode (dry mode) is in conflict with heating mode.
b. Fan mode is in conflict with heating mode and the heating mode is the basic mode. No matter which indoor unit operates first,
the unit will run in heating mode.
2.2 Overload protection function
When the tube temperature is a little low, the compressor raises the operation frequency; when the tube temperature is a little
high, the compressor frequency is restricted or lows down the operation frequency; when the tube temperature is too high, the
compressor protection stops running.
If the discharge temperature protection continuously appears for 6 times, the compressor can't resume running. The
compressor can resume running after cutting off the power and then putting through the power. (if the running time of the
compressor is longer than 7min, the protection times record will be cleared)
2.3 Discharge Protection Function
When the discharge temperature is a little low, the compressor raises the operation frequency; when the discharge temperature
is a little high, the compressor frequency is restricted or lows down the operation frequency; when the discharge temperature is
too high, the compressor protection stops running.
If the discharge temperature protection continuously appears for 6 times, the compressor can't resume running. The
compressor can resume running after cutting off the power and then putting through the power. (if the running time of the
compressor is longer than 7min, the protection times record will be cleared)
Technical Information
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