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49

Outdoor Fan Control

• If the temperature of the indoor heat exchanger rises to 51

°C, outdoor fan stops. The outdoor fan restarts when the indoor heat

exchanger temperature falls to 49

°C.

Compressor high pressure protection

• If the indoor heat exchanger becomes 65

°C or more, the compressor will stop and restart automatically.

(Time Delay Safety Control - 4 minutes waiting).

• This is to reduce the pressure, as to reduce the indoor heat exchanger temp. Nevertheless, is to protect the compressor from

overload of too high temperature.

• 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.

• When compressor stops (reaches room temperature), outdoor fan will operate for 30 seconds (forced operation).
• This is to release the heat and to obtain the lowest pressure as fast as possible.

• 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 39

°C or operation over 4 minutes.

• This operation is to prevent the Cold Draft during Heating mode operation.
• The operation will start when compressor OFF (Thermo OFF) during Heating operation.
• For the first 30 sec. from compressor OFF (Thermo OFF), Indoor fan speed will operate accordingly to the Indoor heat

exchanger temperature as shown below:

50

• After 30 sec. from compressor OFF (thermo OFF), Indoor fan will run at SSLo speed only.
• Anti Cold Draft Control will stop when:

- Intake temperature < set temperature. (Time Delay Safety Control 4 minutes waiting is valid)
- 30 Minutes Time Save Control activates.

Deice starts to prevent frosting at outdoor heat exchanger.

• Normal Deice

Deice operations detection commences after 30 minutes of Heating operation starts or 60 minutes after previous deice
operation. If the TRS (Thermal Reed Switch) senses the outdoor piping temperature drops to -3

°C (TRS CLOSE) or less 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

1. 12 minutes after deicing operation starts;
2. TRS senses the outdoor piping temperature rises to 4

°C (TRS OPEN).

• Once deice operation starts, it will not end for 60 seconds.
• After deice operation, compressor stops for 30 seconds and 4-way valve stays at cooling position for 10 seconds.

Deice will not end immediately as time delay (Td) is valid as shown below:

51

52

1. AUTO OPERATION MODE

The Auto operation will be activated immediately once the Auto OFF/ON button is pressed. This operation can be use 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” sound 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 type 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 unit 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.