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61 

  This unit has built-in with drain pump. 

 
Control content 

  During COOL/DRY mode. 

o  During COOL/DRY mode, drain pump starts 10 seconds after indoor fan motor starts. 
o  The drain pump turns ON and turns OFF periodically. (ON or OFF duration depends on room temperature). 

 

  After COOL/DRY mode, when unit turns OFF (power standby) or changes to HEAT mode. 

o  The drain pump turns ON for 60 seconds immediately. 

 

 Error 

judgment 

o  When float switch detects ON signal continuously for 2 minutes 30 seconds, error code H21 are shown. 
o  When float switch ON has operated 2 times within 20 minutes, error code H35 are shown. 

  A convenience method to activate pump down operation. 

 

  Control start condition: 

o  During power standby condition, short CN-S continuously between 1 second and 10 seconds. 

 

  Control stop condition:  

o  480 seconds after pump down operation starts. 
o  CN-S is shorted again during pump down operation. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

62 

During multi split connection, indoor unit’s operation controls are same with single split connection unless specified in 
this chapter. 

  Capability supply to indoor unit is OFF (Expansion valve closed) when Intake Air Temperature — Internal setting 

temperature < -2.0°C. 

  Capability resume supply to indoor unit after waiting for 3 minutes, if the Intake Air temperature — Internal setting 

temperature > Capability supply OFF point. 

  Capability supply to indoor unit is OFF (Expansion valve closed) when Intake Air Temperature — Internal setting 

temperature < -3.0°C. 

  Capability resume to indoor unit after waiting for 3 minutes, if the Intake Air temperature — Internal setting 

temperature > Capability supply OFF point. 

  Capability supply to indoor unit is OFF (Expansion valve closed) when Intake Air Temperature — Internal setting 

temperature > +1.0°C. 

  During this condition, the indoor fan is stopped if compressor is ON. 

  Capability resume supply to indoor unit after waiting for 3 minutes, if the Intake Air Temperature — Internal 

setting temperature < Capability supply OFF point. 

  Temperature sampling is controlled by outdoor unit where room temperature for all power supply ON indoor unit 

could be obtained. 

  When capability supply to the indoor unit is OFF and the compressor is ON, the indoor fan motor is stopped. 

During this condition, 15 seconds after sampling signal from outdoor unit is received, the indoor fan start 
operation at low fan speed. 

  However, within first 4 minutes of capability stopped supply to the indoor unit, even sampling signal is received, 

the sampling control is cancelled. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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  This mode can be set using remote control and the operation is decided by remote control setting temperature, 

remote control operation mode, indoor intake and outdoor air temperature. 

  During operation mode judgment, indoor fan motor (with speed of -Lo) and outdoor fan motor are running for 

30 seconds to detect the indoor intake and outdoor air temperature. The operation mode is decided based on 
below chart. 

 

 

  Every 180 minutes, the indoor and outdoor temperature is judge. Based on remote control setting temperature, 

the value of T1 will increase up to 10°C, T2 will decrease by 3°C and T3 will decrease up to 8°C. 

  To prevent high pressure at indoor unit, when heating mode thermostat-off condition or power supply OFF, 

indoor fan continue to operate at controlled fan speed for maximum 30 seconds then stop. 

  When the powerful mode is selected, the internal setting temperature will shift lower up to 4.0°C for Cooling/Soft 

Dry or higher up to 6.0°C for heating than remote control setting temperature. This operation stops automatically 
after 20 minutes. 

  When the power supply is cut off during the operation of air conditioner, the compressor will re-operate between 

three to four minutes (10 patterns to be selected randomly) after power resume. 

  During multi split connection, Indoor unit will resume previous mode, include unit standby mode. 

 

LED OFF/ON 

Operation 

Color Green 

Light ON 

Operation ON 

Light OFF 

Operation OFF 

 
Note: 

  If POWER LED is blinking, the possible operation of the unit are Hot Start, during Deice operation, operation 

mode judgment, or ON timer sampling. 

  If Timer LED is blinking, there is an abnormality operation occurs. 

 
 
 
 
 
 

64 

In order to diagnose malfunctions, make sure that there are no 
electrical problems before inspecting the refrigeration cycle. 
Such problems include insufficient insulation, problem with the 
power source, malfunction of a compressor and a fan. 
The normal outlet air temperature and pressure of the refrigeration 
cycle depends on various conditions, the standard values for them 
are shown in the table on the right. 
 
 
 
 

 

 
 
 

Difference in the intake

and outlet

air temperatures 

More than 8°C

(15 minutes after an

operation is started.)

at cooling mode.

Above 14°C

(15 minutes after an

operation is started.)

at heating mode. 

Value of electric

current during operation

Normal

Inefficient compressor

Insufficient refrigerant

Excessive amount

of refrigerant

Dusty condenser

preventing heat radiation

•

•

Less than 8°C at the cooling mode
Less than 14°C at the heating mode.

Higher than specified

Gas side
pressure

Clogged strainer or

capillary tube

•

Cooling Mode

High

Lower than specified

Low

Low

Inefficient compressor

Insufficient refrigerant

Clogged strainer, capillary

tube or expansion valve

Heating Mode

Low

Low

High

Normal Pressure and Outlet Air Temperature (Standard)

 

Gas Pressure 

MPa 

(kg/cm

2

G) 

Outlet air 

Temperature 

(°C) 

Cooling Mode

0.9 ~ 1.2 (9 ~ 12) 

13 ~ 17 

Heating Mode 2.0 ~ 2.7 (20 ~ 27) 

32 ~ 42 

*Condition:  • Indoor fan speed = High 

• Outdoor temperature 35°C at the cooling 

                      mode and 7°C at the heating mode 
                    • Compressor operates at rated frequency