SEQUENCE OF OPERATION
PAGE 25
ENGLISH
Auto Mode
With the system turned on, press the AUTO button on the 
remote control. The system will change to the auto mode of 
operation.
As the room is cooled or heated, the system will automati-
cally switch between cool mode, fan mode, and heat mode. 
There is a minimum 15 minute operating time between mode 
changes. 
Dry Mode
 
 
Overview
 
The temperature control range in Dry mode is 60°F - 86°F. 
This mode is used for the purpose of dehumidication.
(Tr = room temperature  Ts = set temperature)
When Tr > Ts + 4°F, the compressor will turn on and the indoor 
fan will operate at the set speed.
When Ts ≤ Tr ≤ Ts + 4°F, the compressor will operate at the 
high dry frequency for 10 minutes, then at the low dry mode 
for 6 minutes. The indoor fan will operate at low speed.
When Tr < Ts, the outdoor unit will stop, and the indoor fan will 
stop for 3 minutes, then operate at the low speed option.
Automatic fan speed:
When Tr >= Ts + 9°F, High speed
When Ts + 5.4°F ≤ Tr < Ts + 9°F, Medium speed
When Ts + 3.6°F ≤ Tr < Ts + 5.4°F, Low speed   
When Tr < Ts + 3.6°F, Light speed
Note: TURBO and QUIET mode must be set using the remote 
controller.
If the outdoor fan is stopped, the indoor fan will pause for 3 
minutes. 
If the outdoor fan is stopped for more than 3 minutes, and the 
compressor is still operating, the system will change to light 
speed mode. 
 
Indoor unit
 
To enter the dry mode, point the infrared remote control at 
the indoor unit and press the power button, then press the 
DRY mode button if not already set to dry mode. 
The signals received by the infrared receiver are relayed to 
the main board of the indoor unit to turn the system on and 
set it to dry mode.
The indoor unit main board will activate the display of the 
indoor unit, illuminating the display, indicating the room tem-
perature and current status of the unit.
The indoor unit main board will signal the louver stepper mo-
tor to open the louver to either a stationary position, or one 
of several oscillating modes. 
As the louver opens, the indoor unit main board will power up 
the indoor fan motor, operating the fan at the speed last set. 
The indoor fan motor has a feedback circuit which provides 
the indoor unit main board with information for controlling 
the speed of the fan motor. (See overview section for more 
information.)
 
Temperature Sensors
 
The indoor unit has two sensors that provide temperature 
information to the indoor unit main board. An indoor ambient 
temperature sensor, and coil temperature sensor are used for 
controlling the system during dry mode. The resistance val
-
ues of the sensors will vary with temperature. The resistance 
to temperature values can be found using a temperature / 
resistance chart specic to the sensor being checked.
 
Communication
 
The indoor and outdoor unit main boards communicate via 
a digital signal on the wire connected to terminal 3C of each 
unit. A splice or break in this wire will cause a communication 
error.
When a command is received from the remote control, the 
indoor unit main board communicates with the outdoor unit 
main board via the terminal 3C wire to perform the requested 
function.    
 
Outdoor Unit
 
Upon a request for dry mode, the outdoor unit main board 
applies power to the outdoor fan motor and compressor. 
Depending on system cycling, there may be up to a 3 minute 
wait period before the compressor and outdoor fan start.) 
WARNING: Do not measure compressor voltages, damage to 
the volt meter may result.  
The outdoor unit main board also controls the position of 
the EEV (Electronic Expansion Valve) to regulate the ow of 
refrigerant to the indoor unit evaporator coil.    
 
Temperature Sensors
 
Four temperature sensors located in the outdoor unit provide 
temperature information to the outdoor unit main board for 
control of the system during dry mode.
The outdoor ambient temperature sensor provides the tem-
perature of the air drawn into the outdoor coil of the outdoor 
unit.
The defrost temperature sensor provides the temperature 
sensed at the output of the outdoor coil.