Description Of Each Control Operation - Gree GVC24AMXF-K3NTC7A Service Manual

6. Function and Control
Service Manual

6.5 Description of Each Control Operation

1. Summary
Temperature parameter
◆ Indoor set temperature (Tpreset)
◆ Indoor ambient temperature (Tamb.)
◆ Inner tube temperature of indoor evaporator (Ttube)
2. Introduction of basic mode function
Once the compressor is energized, there should be a minimum
interval of 3 mins between two start-ups.
If the unit is with memory function and is off before power failure,
the compressor can be restarted without an interval of 3 mins;
if the unit is on before power failure, the compressor will be
restarted with an interval of 3 mins.
Once compressor is started, it won't stop within 6 mins according
to the change of room temp.
(1) Auto mode
① Operation condition and process
Under auto mode, the system will automatically select operation
mode (cooling, dry, heating and fan) according to indoor ambient
temperature.
◆ When Tamb. > 26°C, the system operates under cooling
mode; Ex-factory set temperature is 26°C.
◆ When 20°C ≤ Tamb. ≤ 26°C, the system operates under
drying mode; Ex-factory set temperature is 24°C.
◆ Heat pump unit: when Tamb. < 20°C, the system operates
under heating mode; Ex-factory set temperature is 20°C.
◆ Cooling only unit: when Tamb. < 20°C, the system operates
under fan mode; Ex-factory set temperature is 20°C.
② Protection function is same as that under cooling, drying and
heating mode. (See function protection of this section)
(2) Cooling mode
① Operation condition and process
◆ When Tamb. ≥ Tset+1°C, the system operates under cooling
mode. In this case, the compressor and the ODU fan motor
operate, and the IDU fan motor operates at set speed.
◆ When Tset-1°C < Tamb. < Tset+1°C, the system will maintain
its previous operation status.
◆ When Tamb. ≤ Tset-1°C, the compressor and the ODU fan
motor stop, while the IDU fan motor operates at set speed.
In cooling mode, the 4-way valve is de-energized (4-way valve is
not available for cooling only unit). Temperature setting range is
16°C ~ 30°C.
② Protection function (See function protection of this section)
Technical Information
Tamb.
Tpreset +1 ˚C
Tpreset –1 ˚C
6 min. 3 min.
Compressor
Outdoor fan motor
Indoor fan motor
Set fan speed
Graphic instruction: (Same as below)
(3) Drying mode
① Operation condition and process
◆ When Tamb. > Tset+2°C, the system starts drying and
cooling. In this case, the compressor and the ODU fan motor
operate, and the IDU fan motor operates at low speed.
◆ When Tset-2°C ≤ Tamb. ≤ Tset+2°C, the compressor and the
ODU fan motor operate for 6 mins and stop for 4 mins in cycle;
the IDU fan motor operates at low speed.
◆ When Tamb. < Tset-2°C, the compressor and the ODU fan
motor stop, while the IDU fan motor runs at low speed.
In drying mode, the 4-way valve is de-energized (4-way valve is
not available for cooling only unit); Temperature setting range is
16°C~30°C. Fan speed can't be adjusted.
② Protection functions (See function protection of this section)
T
amb.
T +2
preset
T 2
preset-
Compressor
Outdoor fan motor
Indoor fan motor
(4) Heating mode(heating mode is not available for cooling
only uni)
① Operation condition and process
◆ When Tamb. ≤ Tset-1°C, the system starts heating operation.
In this case, the 4-way valve is energized. The compressor and
the ODU fan motor operates simultaneously; The IDU fan motor
will be started up after delayed for a period of time to make sure
the air conditioner won't blow out cold wind.
◆ When Tpreset-1°C < Tamb. < Tpreset+1°C, the system keeps
previous operation status.
◆ When Tamb. ≥ Tpreset+1°C, the compressor and the ODU
fan motor stop. The 4-way valve is energized all the time. The
Start cooling
Original operating status
Stop cooling
6 min.
Indicates operation Indicates stop
Cooling
Drying
Stop
6 min 6min.
4min.
4min.
Low speed
31