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  The indoor fan will operate according to pattern below. 

 

 

 
[Heating] 

  According to indoor pipe temperature, automatic heating fan speed is determined as follows. 

 

 

 

  Immediately after the fan motor started, feedback control is performed once every second. 

  During fan motor on, if fan motor feedback ≥ 2550 rpm or < 50 rpm continue for 10 seconds, then fan motor error 

counter increase, fan motor is then stop and restart. If the fan motor counter becomes 7 times, then H19 - fan 
motor error is detected. Operation stops and cannot on back. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

58 

To provide quiet cooling operation compare to normal operation. 
 

B. Control condition 
a. Quiet operation start condition 

  When “quiet” button at remote control is pressed. 

 

b. Quiet operation stop condition 

1  When one of the following conditions is satisfied, quiet operation stops: 

a. 

Powerful button is pressed. 

b. 

Stop by OFF/ON switch. 

c. 

Timer “off” activates. 

d. 

Quiet button is pressed again. 

2  When quiet operation is stopped, operation is shifted to normal operation with previous setting. 
3  When fan speed is changed, quiet operation is shifted to quiet operation of the new fan speed. 
4  When operation mode is changed, quiet operation is shifted to quiet operation of the new mode. 
5  During quiet operation, if timer “on” activates, quiet operation maintains. 
6  After off, when on back, quiet operation is not memorised. 

 

1  Auto fan speed is changed from normal setting to quiet setting of respective fan speed. 

This is to reduce sound of Hi, Me, Lo for 3dB. 

2  Manual fan speed for quiet operation is 1 step from setting fan speed. 
3  Compressor frequency reduced. 

To provide quiet heating operation compare to normal operation. 
 

B. Control condition 
a. Quiet operation start condition 

  When “quiet” button at remote control is pressed. 

 

b. Quiet operation stop condition 

1  When one of the following conditions is satisfied, quiet operation stops: 

a. 

Powerful button is pressed. 

b. 

Stop by OFF/ON switch. 

c. 

Timer “off” activates. 

d. 

Quiet button is pressed again. 

2  When quiet operation is stopped, operation is shifted to normal operation with previous setting. 
3  When fan speed is changed, quiet operation is shifted to quiet operation of the new fan speed. 
4  When operation mode is changed, quiet operation is shifted to quiet operation of the new mode. 
5  During quiet operation, if timer “on” activates, quiet operation maintains. 
6  After off, when on back, quiet operation is not memorised. 

 
C. Control contents 
a. Fan Speed Auto 

  Indoor FM RPM depends on pipe temperature sensor of indoor heat exchanger. 

Auto fan speed is changed from normal setting to quiet setting of respective fan speed. 
This is to reduce sound of Hi, Me, Lo for 3dB. 

 
b. Fan Speed Manual 

  Manual fan speed for quiet operation is - 1 step from setting fan speed. 

 
c. Compressor frequency reduced. 
 
 
 
 

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When the powerful mode is selected, the internal setting temperature will shift higher up to +6.0°C (for Heating) or 
lower up to 4°C (for Cooling/Soft Dry) than remote control setting temperature for 20 minutes to achieve the setting 
temperature quickly. 

ON timer can be set using remote control, the unit with timer set will start operate earlier than the setting time. This is 
to provide a comfortable environment when reaching the set ON time. 
 
60 minutes before the set time, indoor (at fan speed of Lo-) and outdoor fan motor start operate for 30 seconds to 
determine the indoor intake air temperature and outdoor air temperature in order to judge the operation starting time. 
 
From the above judgment, the decided operation will start operate earlier than the set time as shown below. 

 

 

OFF timer can be set using remote control, the unit with timer set will stop operate at set time. 

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

three to four minutes (there are 10 patterns between 2 minutes 58 seconds and 3 minutes 52 seconds to be 
selected randomly) after power supply resumes. 

2  This type of control is not applicable during ON/OFF Timer setting. 
3  This control can be omitted by open the circuit of JP10 at indoor unit printed board. 

 

LED OFF/ON 

Operation 

Color Green 

Light ON 

Operation ON 

Light OFF 

Operation OFF 

Note: 

  If OFF/ON operation LED is OFF and OFF indicator does not shown on remote control display, there is an 

abnormality operation occurs. 

 
 
 
 
 
 
 
 
 

60 

  Enable digital connection from indoor unit to external devices. 

 Control 

items: 

1 Start/stop 

input. 

2  Start/stop signal output. 

 

 

 

 Condition 

1  1-2 (Pulse input): Unit ON/OFF condition switching with a pulse signal.  

(1 pulse signal: shortage status 200~300msec) 

2  3-4 (Static output): 5V output during the unit ON. No output at OFF. 
 
Example of wiring: 
 

 

 

Note: The wire length from indoor unit to the external interface must be within 1.9 meters. The wire must be double 
insulation type and a ferrite core to be added to reduce noise. Proposed core spec is J0KE00000147 with Heat 
Shrinkage Tube. 
 
The signal between indoor unit and the external interface must be isolated by photo-coupler of approval type 
(e.g: Semko, VDE etc). 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

ON/OFF input

(Pin 1-2) 

Monitor output

(Pin 3-4) 

ON

ON

OFF

Unit condition

200~300msec

+5V

MCU

HAJEM-A

(XH type)

Indoor Unit

PCB

+5V

1

1

1

1

#A4

#A4

#B4

240 mm

Max 1900 mm

#A K1KA04AA0347 (Maker: JST; Maker code: B4B-XH-TV4)
#B Maker: JST; Maker code: XHP-4

#B4

Core

4T