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• When the thermo-off temperature (temperature which compressor stops to operate) is reached during:-

- Heating operation - the compressor stops for 3 minutes (minimum) before resume operation.

• If the operation is stopped by the remote control, the compressor will not turn on within 3 minutes from the moment operation

stop, although the unit is turn on again within the period.

• This phenomenon is to balance the pressure inside the refrigerant cycle.

• If the compressor is operating continuously for 5 minutes or longer and the temperature difference between indoor heat

exchanger and intake air is 5°C or less for continuous 2 minutes, compressor will stop and restart automatically.

• Time Delay Safety Control is activated before the compressor restart.

▲ T = Indoor heat exchanger temperature - Intake air temperature

• This is to prevent compressor from rotate reversely when there is an instantaneous power failure.

• Outdoor Fan Control

- If the temperature of the Outdoor Heat Exchanger less than -3°C, Outdoor Fan is ON. The Outdoor Fan stop, when Outdoor

Heat Exchanger temperature is Tb or more according to Outdoor Air Temperature region as table below:
The Outdoor Fan restarts when the indoor heat exchanger temperature falls to 49°C.

During starting of Heating mode and after deice, Outdoor Fan ON for 90 sec. (Hi).

• Compressor High Pressure Control

- If the indoor heat exchanger becomes 68°C or more, the compressor will stop and restart automatically.
- Time Delay Safety Control is activated before the compressor restart.

• 4-way valve always on during Heating operation. (except deicing operation)
• When the unit is switched off by remote control during Heating operation, the 4-way valve stay at Heating position for 5 minutes.
• This is to prevent the refrigerant flow process sound for being occur.

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• Hot Start Control is to prevent cool air discharge into the room when heating operation start.
• When Heating operation starts, Indoor fan will not start until the indoor heat exchanger reaches 30°C as diagram shown.

• Hot start is completed when indoor heat exchanger rises to 42°C or operation over 4 minutes.

Deice starts to prevent frosting at outdoor heat exchanger.

• Normal Deice

Deice operation detection commences in Heating operation starts or 60 minutes after previous deice operation. If the outdoor
piping temperature drops to -4°C for 50 sec. continuously during compressor is in operation, deice will start.
(There is no detection during Outdoor Fan stops.)

• Overload Deice

During heating operation, if the outdoor Fan OFF duration (due to overload protection control) is accumulated up to 60 minutes
and after compressor starts for 1 minutes, deice starts.

• Deice ends when

(a) 12 minutes after deicing operation starts;
(b) The outdoor piping temperature rises to about 12°C.

• After deice operation, compressor stops for 30 seconds and 4-way valve stays at cooling position for 10 seconds.

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1. AUTO OPERATION MODE

The Auto operation will be activated immediately once the Auto OFF/ON button is pressed. This
operation can be used to operate air conditioner with limited function if remote control is misplaced or
malfunction.

2. TEST RUN OPERATION (FOR PUMP DOWN/SERVICING PURPOSE)

The Test Run operation will be activated if the Auto OFF/ON button is pressed continuously for more
than 5 seconds. A “beep” sound will occur at the fifth seconds, in order to identify the starting of Test
Run operation.

3. REMOTE CONTROL RECEIVING SOUND OFF/ON MODE

The Remote Control Receiving Sound OFF/ON operation will be activated if (within 20 seconds of Test
Run Operation) the Auto OFF/ON button is pressed for more than 5 seconds. 2 “beep” sounds will occur
at to identify the starting of Remote Control Receiving Sound Off/On Mode.

Press “Auto OFF/ON” button to toggle remote control receiving sound.

• Short “beep”: Turn ON remote control receiving sound.
• Long “beep”: Turn OFF remote control receiving sound.

After “Auto OFF/ON” button is pressed, the 20 seconds counter for Remote Control Receiving Sound
OFF/ON Mode is restarted.

• There are 4 types of remote control transmission code could be selected and stored in EEPROM of indoor unit. The indoor unit

will only operate when received signal with same transmission code from remote control. This could prevent signal interference
when there are 2 or more indoor units installed nearby together.

• To change remote control transmission code, short or open jumpers at the remote control printed circuit board.

• During Remote Control Receiving Sound OFF/ON Mode, press any button at remote control to transmit and store the desired

transmission code to the EEPROM.