Gree GWH18MC-K3DNA2G Service Manual page 33

Service Manual
2. Temperature setting range
(1) If T ≥ [T ], the temperature can be set at: 16~30ºC (Cooling at room temperature);
outdoor ambient temperature low-temperature cooling temperature
(2) If T < [T ], the temperature can be set at: 25~30ºC (Cooling at low temperature), that is, the
outdoor ambient temperature low-temperature cooling temperature
minimum setting temperature for outer units judgment is 25ºC .
(2) Dehumidifying Mode
1. Conditions and processes of dehumidifying operations: Same as the cooling mode;
2. The temperature setting range is: 16~30ºC ;
(3) Air-supplying Mode
1. The compressor, outdoor fans and four-way valves are switched off;
2. The temperature setting range is: 16~30ºC.
(4) Heating Mode
1. Conditions and processes of heating operations: (T is the actual detection temperature of indoor environment thermo-bulb,
indoor ambient temperature
T is the indoor ambient temperature compensation during heating operations)
heating indoor ambient temperature compensation
(1) If the compressor is shut down, and [(T – ⊿ T ) –T ] ≤ 0.5ºC, start the machine to
indoor ambient temperature heating indoor ambient temperature compensation setup
enter into heating operations for heating;
(2) During operations of heating, if 0ºC ≤ [(T – ⊿ T ) –T ] < 2ºC, the heating operation
indoor ambient temperature heating indoor ambient temperature compensation setup
will be still running;
(3) During operations of heating, if 2ºC ≤ [(T – ⊿ T ) –T ], the heating operation will stop
indoor ambient temperature heating indoor ambient temperature compensation setup
after reaching the temperature point.
2. The temperature setting range in this mode is: 16~30ºC .
3. Special Functions
Defrosting Control
① Conditions for starting defrosting
After the time for defrosting is judged to be satisfied, if the temperature for defrosting is satisfied after detections for continuous 3minutes, the
defrosting operation will start.
② Conditions of finishing defrosting
The defrosting operation can exit when any of the conditions below is satisfied:
③ T ≥ (T – [T ];
outdoor pipe temperature outdoor ambient temperature temperature 1 of finishing defrosting
④ The continuous running time of defrosting reaches [tmax. defrosting time].
4. Control Logic
(1) Compressor Control
Start the compressor after starting cooling, heating, dehumidifying operations, and the outer fans start for 5s; When the machine is shutdown,
in safety stops and when switching to air-supplying mode, the compressor will stop immediately. In all modes: once the compressor starts up,
it will not be allowed to stop until having run for the [tmin. compressor running time] (Note: including cases of shutdown when the temperature
point is reached; except the cases requiring stopping the compressor such as fault protection, remote shutdown, mode switching etc.); In all
modes: once the compressor stops, it will be allowed be restart after 3-minute delay (Note: The indoor units have a function of power memory,
the machine can be restarted after remote shutdown and powering up again without delay).
1. Cooling mode
Start the machine to enter into cooling operation for cooling, the compressor is switched on.
2. Dehumidifying mode
Same as the cooling mode.
3. Air-supplying mode
The compressor is switched off.
4. Heating mode
(1) Start the machine to enter into heating operation for heating, the compressor is switched on.
(2) Defrosting:
a. Defrosting starts: the compressor is shut down, and restarts it after 55-second delay.
b. Defrosting ends: the compressor stops, then starts it after 55-second delay.
(2) Outer Fans Control
Notes:
Only the outer fans run for at least 80s in each air flow speed can the air flow be switched;
After the outer fans run compulsively in high speed for 80s when the machine starts up, control the air flow according to the logic.
After remote shutdown, safety stops, and when the machine stops after reaching the temperature point, as well as after the compressor stops,
Technical Information
30