Control Function Of Outdoor Unit; Dry Mode; Heating Mode - Gree GWHD14NK3BO Service Manual

Function and Control
(2)Models:36K,42K

1.Control Function of Outdoor Unit

1.1 Cooling Mode
a. Cooling conditions and process:
If the compressor is in stop status and start the unit for cooling operation, when one of the indoor units reaches the cooling
operation condition, the unit start cooling operation; in this case, the electronic expansion valve, the outdoor fan and the
compressor start operation.
a) Compressor stops
The compressor stops gradually, the outdoor fan stops after 1min.
required frequency. For the indoor unit with no requirement, the corresponding electronic expansion valve is closed to 0P.
c. Cooling mode transfers to heating mode
When the unit transfers to heating mode, the 4-way valve is energized after the compressor runs for 40s. The other disposals
are the same as stopping in cooling mode.
d. 4-way valve:
In this mode, the 4-way valve is closed.
e. Outdoor fan control in cooling mode
then it will run in set speed.
according to the indoor units quantity and outdoor temperature.); When the compressor stops, the outdoor fan runs at present
speed and stops after 1min.

1.2 Dry Mode

a. The dry conditions and process are the same as those in cooling mode;
c. The temperature setting range: 16 ~ 30 ;
d. Protection function: the same as those in cooling mode;
e. In dry mode, the maximum value A of the capacity requirement percentage of single unit is 90% of that in cooling mode. The
open condition of the electronic expansion valve, outdoor fan and compressor is the same as those in cooling mode.

1.3 Heating Mode

a. Heating conditions and process: When one of the indoor units reaches the heating operation condition, the unit starts heating
operation.
a) When all the indoor units reach the stop condition, the compressor stops and the outdoor fan stops after 1min;
according to the required frequency;
c) Heating mode transfers to cooling mode(dry mode), fan mode
The compressor stops;
The outdoor fan stops after 1min;
The status of 4-way valve: energized;
c. Outdoor fan control in heating mode
every speed for at least 80s; When the compressor stops, the outdoor fan stops after 1min.
d. Defrosting function
When the defrosting condition is met, the frequency of the compressor starts to decrease and wait for defrosting; the electronic
valve reverses the direction; after the 4-way valve reverses the direction, the frequency of the compressor starts to rise; then
e. Oil-returned control in heating mode
a) Oil-returned condition
The whole unit is operating in low frequency for a long time
The indoor unit displays "H1"
The duration reaches 5min
1.4 Fan Mode
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