14
Technical Information
Service Manual
6.2 Brief Description of Modes and Functions
1. Summary
(1) Buzzer
When the controller is energized or receives signal from button (emergency operation switch on air conditioner) or remote controller, the
buzzer will give out a beep.
(2) Display
◆
After energization, all icons will be displayed once. Operation icon is in red under standby status. After turning on the unit by remote
controller, operation icon is bright and corresponding set operation mode icon will be displayed (Mode icon include: cooling, heating,
drying).
(3) 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 for auto mode
Under auto mode, the system will automatically select operation mode (cooling, heating, and fan) according to indoor ambient
temperature. There swill be 30s delayed for protection between mode switchover.
◆
When Tamb≥26 , unit will be in cooling mode
℃
Ex-factory set temperature is 20
℃
◆
Cooling and heating unit: When Tamb≤(19
℃
+Tcompensation), unit will be in heating mode Tpreset=20
℃
.
◆
Cooling only unit: When Tamb≤22
℃
(or 72
℉
), unit will be in fan mode Tpreset=25
℃
.
◆
For cooling and heating unit under condition that (19
℃
+Tcompensation)
<
Tamb
<
26
℃
(For cooling only unit under condition that
22
℃<
Tamb
<
26
℃
), when unit is initially turned on in auto mode, it will operate according to auto fan mode. When unit is changed to
auto mode from other modes, it will maintain its previous working status (If auto mode is turned on from
drying mode, unit will operate according to auto fan mode).
②
Display: Operation icon, actual operation mode icon, set temperature (that’s the display content of dual-8 nixie tube)
③
Protection function is same as that under each mode.
(2) Cooling mode
①
Operation condition and process for cooling mode
◆
When Tamb. ≥Tset+1
℃
, the system operates under cooling mode. In this case, the compressor, the ODU fan motor and the IDU fan
motor operates at set speed.
◆
When Tamb. ≤Tset-1
℃
, the compressor and the ODU fan motor stop, while the IDU fan motor operates at set speed.
◆
When Tset-1
℃
<Tamb. <Tset+1
℃
, the system will maintain its previous operation status.
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
℃
.
②
Display: Operation icon, cooling icon, set temperature.
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
Heating
indicator
Temp.
indicator
Cooling
indicator
Power
indicator
Receiver
window
drying
indicator