Specifications

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2) Start of protection for compressor
When the inverter decision frequency is 36 Hz or more, compressor protection starts.
1 Start of protection I (When the unit is started after 6 hours or more have elapsed since the last compressor stop.)
After the compressor has been started, the frequency of the outdoor unit is maintained at a maximum of 60 Hz for 5
minutes, after which transition is made to the decision frequency.
2 Start of protection II (Other than item 1 )
After the compressor has been started, the frequency of the outdoor unit is maintained at 48 Hz for 1 minute and 45
seconds, after which transition is made to the decision frequency.
3 Start of protection III (The first time after the power is turned on and when starting when the total power-on time is
less than 6 hours.)
After the compressor has been started, it is operated at 28 Hz for 1 minute. Then for the next 10 minutes it increases
at a rate of 2 Hz every 30 seconds to the upper limit frequency of the outdoor unit. For the next 4 minutes, the
increase is 2 Hz every 15 seconds.
4 The 4-way valve protection (When the unit is started under the decision frequency of less than 36Hz). The unit is
operated for 30 seconds under the outdoor unit's frequency of 36Hz and then it is operated in accordance with the
decision frequency.
3) Delay of compressor start
If the compressor (inverter) is stopped by the operation of the cooling or heating thermostat, the operation switch on the
remote controller or an abnormality, it cannot be restarted for 3 minutes.
However, turning on the power disables the 3-minute timer.
(b) Heating overload protection control
When the outdoor units are operating at a frequency other than 0 Hz and the outdoor air temperature is 12°C or more for 30
continuous seconds, the outdoor fan speed is reduced by one step to perform the current safe control. However, when one unit
is operating, the outdoor frequency is forced to 30 Hz. Recovery is when the outdoor air temperature is 10°C or less.
(c) Cooling overload protection control
When the outdoor units are operating at a frequency other than 0 Hz and the outdoor air temperature is 39°C or more for 3
continuous minutes, the fan speed of the outdoor unit is increased 1 speed and the current safe control operates. Recovery is
when the outdoor air temperature is 38°C or less.
(d) Low Hz continuous operation protection control
The following controls are performed to return the oil to the compressor when the outdoor frequency is less than 34 Hz and
28 Hz or more for 20 continuous minutes or more.
1) Forced operation at outdoor frequency of 34 Hz is performed for 1 minute.
2) The outdoor fan operates according to decision frequency and the expansion valve operates according to the outdoor
frequency.
3) If the unit receives a command of that is higher than 34 Hz when operating at the forced 34 Hz, it will respond to the
higher command and the operation of this control is ended.
(e) High Hz continuous operation protection control
The following controls are performed to protect the compressor when the outdoor frequency is 110 Hz or higher for 9
continuous minutes or more.
1) Forced operation at outdoor frequency of 108 Hz is performed for 1 minute.
2) The outdoor fan operates according to decision frequency and the expansion valve operates according to the outdoor
frequency.
3) If the unit receives a command of that is lower than 108 Hz when operating at the forced 108 Hz, it will respond to the
higher command and the operation of this control is ended.
(f) Heating low temperature protection control
The following controls are performed during heating operation when operating at an outdoor frequency other than 0 Hz and
the temperature detected by the outdoor air temperature thermistor is 2°C or less for 1 continuous minute.
1) The fan speed of the outdoor unit is forced one speed higher.
2) When the outdoor air temperature thermistor reaches 4°C or more, the operation of this control is ended.
(g) Current cut
An abnormal stop is made if the converter output current at the shunt resistor exceeds the set value. At the same time, LED 5
on the printed circuit board for the outdoor unit will flash 1 time at a 0.5 second interval every 8 seconds.
The unit is re-started after the stop mode, however, if the current cut has been operated 3 times at less than 28 Hz, the fourth
start cannot be performed. (The timer lamp on the indoor unit will flash 1 time.)