Service Manual
25
Installation and Maintenance
6.3 Introduction of Each Mode Function
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
℃
, the system operates under cooling mode; Ex-factory set temperature is 26
℃
.
◆
When 20
℃
≤Tamb.≤26
℃
, the system operates under drying mode; Ex-factory set temperature is 24
℃
.
◆
Heat pump unit: when Tamb.
＜
20
℃
, the system operates under heating mode; Ex-factory set temperature is 20
℃
.
◆
Cooling only unit: when Tamb.
＜
20
℃
, the system operates under fan mode; Ex-factory set temperature is 20
℃
.
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
℃
, 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
℃＜
Tamb.
＜
Tset+1
℃
, the system will maintain its previous operation status.
◆
When Tamb.≤Tset-1
℃
, 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
～
30
℃
.
Indicates operation
Indicates stop
T1 ˚C
Tpreset –1 ˚C
Compressor
Outdoor fan motor
Indoor fan motor
Graphic instruction:
(Same as below)
Tamb.
Stop cooling
Start cooling
Original operating status
6 min.
3 min.
6 min.
Set fan speed
②
Protection function (See function protection of this section)
(3) Drying mode
①
Operation condition and process
◆
When Tamb.
＞
Tset+2
℃
, 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
℃
≤Tamb.≤Tset+2
℃
, the compressor and the ODU fan motor operate for 6 mins and stop for 4 mins in cycle; the IDU
