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9.3.5. Dew form prevention control
• During cool or dry operation, if outdoor temperature is less than 30°C, and indoor fan speed is low or auto setting, indoor heat
exchanger temperature become lower, dew form prevention control start to prevention dew form at indoor discharge grill.
• Indoor evaporator temperature area is divided into 4 zones, which consist of, down zone, no change zone, up zone, and
recovery zone.
• When indoor evaporator temperature is going into each zone, change compressor frequency by following the below table.
Recovery zone
Release dew form prevention operation
No change zone
Continue check the indoor heat exchanger temperature
Down zone
Reduce the compressor frequency
(check for 3 min, max 3 times)
(check for 3 min, max 3 times)
9.3.6. Cooling low temperature protection control
• During cooling, or dry operation, if outdoor temperature is less than -15°C.
− And thermostat on condition continue for 15 min, compressor stop.
− After 3 min waiting (restart delay), if thermostat is on, compressor restart.
− After 3 min waiting (restart delay), if thermostat is on, compressor restart.
9.4. Heating mode operation
9.4.1. Heating indoor fan control
Fan speed manual
• Fan speed [Hi] [Me] [Lo] set by remote controller.
• However, when operation start, or during operation, fan speed control is limited to due to prevent a cold draft, for example, when
• However, when operation start, or during operation, fan speed control is limited to due to prevent a cold draft, for example, when
heating operation start.
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Fan speed auto
• When operation start, or during operation, fan speed control by detecting indoor heat exchanger as follows:
9.4.2. Hot start control
• When heating operation start, hot start control carry out.
• During hot start operation, [PREHEAT] displayed at the wired remote controller.
• For wireless remote controller, [POWER LED] is blinking at the receiver of indoor unit. Indoor fan stop and louver angle fixed
• During hot start operation, [PREHEAT] displayed at the wired remote controller.
• For wireless remote controller, [POWER LED] is blinking at the receiver of indoor unit. Indoor fan stop and louver angle fixed
to upper side in spite of any setting of remote controller. When indoor heat exchanger temperature increase, or 4 minutes past
after operation start, hot start control finish and shift to normal fan control.
after operation start, hot start control finish and shift to normal fan control.
9.4.3. Cold draught prevention control
• This control is to prevent cold draught during heating mode operation.
• The operation will start when the compressor is OFF (thermostat off) during heating operation.
• Initially, the AC indoor fan motor will operate at Lo speed for 2 minutes.
• After this, the AC indoor fan stops for 3 minutes and then operates at Lo speed for 10 seconds. And this operation repeats as
• The operation will start when the compressor is OFF (thermostat off) during heating operation.
• Initially, the AC indoor fan motor will operate at Lo speed for 2 minutes.
• After this, the AC indoor fan stops for 3 minutes and then operates at Lo speed for 10 seconds. And this operation repeats as
cold draught prevention control is on.
• The cold draught prevention control stops when the compressor is ON (thermostat on).
9.4.4. Heating powerful operation
• When heating mode operation start, temperature differences between setting temperature and room temperature is more than
5 K, setting temperature increase 2 K and operation start.
(however, setting temperature after shifting is more than 31°C, setting temperature fixed 31°C.)
• Due to this control, micro computer judge indoor heat loss is big and increase compressor frequency compare to normal
condition, then heat up indoor room quickly.
• This control will be finished after 60 min or thermostat is off.
9.4.5. Defrost control
• During heating operation at outdoor low temperature condition, defrost operation start timely to melt the ice formed on outdoor
heat exchanger.
• When heating operation accumulated time is time up, and both outdoor temperature and outdoor unit heat exchanger
temperature is less than setting temperature for 5 minutes. When defrost temperature is more than setting temperature, defrost
operation finish.
operation finish.
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• During defrost operation, in spite of any change of remote controller, indoor fan stop.
• During defrost operation, [DEFROST] is displayed at wired remote controller, hot start operate after defrost operation finish.
• The defrost temperature (DEF_Th) depends on outdoor ambient temperature.
• During defrost operation, [DEFROST] is displayed at wired remote controller, hot start operate after defrost operation finish.
• The defrost temperature (DEF_Th) depends on outdoor ambient temperature.
Outdoor air temp. (°C)
Maximum defrost time
DEF_Th (°C)
Tout
-3°C
10min 30sec
11°C
-3°C > Tout
-10°C
10min 30sec
5 °C
Tout < -10°C
10min 30sec
3°C
9.4.6. Heating high temperature protection
• During heating operation, when outdoor temperature is more than 35°C for 15 minutes, compressor stop to protect compressor.
• After 3 minutes (re-start delay control) waiting, if thermostat on condition, outdoor unit re-start.
• After 3 minutes (re-start delay control) waiting, if thermostat on condition, outdoor unit re-start.
9.5. Odour removing operation
• During stop condition, or cooling operation, when pushing the [ODOUR] button for 3 seconds, operation change to the odour
removing operation.
• Operation detail is as follows;
Fan mode operation for 180 seconds, then refrigerant cycle change to heating mode for 720 seconds, to heat up (dry) the
indoor unit. Compressor frequency and indoor fan controlled to maintain the indoor heat exchanger temperature 41°C.
indoor unit. Compressor frequency and indoor fan controlled to maintain the indoor heat exchanger temperature 41°C.
• Indoor fan revolution is fixed at Lo speed.
• After that, fan mode operation continue for 360 seconds, then odour removing operation finish.
• During odour removing operation, [ODOUR] sign is blinking at LCD display panel of wired remote controller, when pushing the
• After that, fan mode operation continue for 360 seconds, then odour removing operation finish.
• During odour removing operation, [ODOUR] sign is blinking at LCD display panel of wired remote controller, when pushing the
operation button, or [ODOUR] button, odour removing operation finish and set the odour cut operation.
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9.6. Energy save operation
• During cooling operation, or heating operation, when pushing the [ECONOMY] button in the wired remote controller, energy
save operation start and [ECO] sign is displayed at LCD display panel of wired remote controller ([ECONOMY] sign is displayed
at LCD display panel of wireless remote controller).
at LCD display panel of wireless remote controller).
• When energy save operation start and temperature differences is +1K (=indoor suction temperature - setting temperature) for
cooling operation, or -1K for heating operation for 30 minutes, thermostat OFF point shift to 0.5K.
(This means thermostat OFF point shift up +0.5K for cooling, thermostat OFF point shift down -0.5K for heating)
From this control, it is judged that indoor side heat loss is small, then reduce compressor frequency. This means energy save
operation.
operation.
• Those kind of operation continue maximum 4 times. If temperature is out of range (thermostat off +1K for cooling, thermostat
off -1K for heating), operation release from energy save control. But energy save control cannot be released by pushing
ON/OFF button of remote controller, but still effective. When pushing [ECONOMY] button once again, energy save control
released.
ON/OFF button of remote controller, but still effective. When pushing [ECONOMY] button once again, energy save control
released.
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