11-7
CONTROL SYSTEM
SM HDDHED 1-A.1 GB
11.11.1
Indoor Coil Defrost Protection
Conditions for Start Controlling
Judge the controlling start with the ICT (Indoor Coil Temperature) after 2 sec from operation start.
During cooling operation, the signals being sent from the indoor unit allow the operating frequency
limitation and then prevent freezing of the indoor heat exchanger.
Compressor will stop when ICT <= -1
o
C for continuous 3 mins.
If the unit stops as such protection for 6 times, it can not resume running automatically and display
malfunction, it can resume by pressing ON/OFF.
11.11.2
Indoor Coil over Heating Protection
Conditions for Start Controlling
Judge the controlling start with the ICT after 2 sec from operation start.
During heating operation, the signals being sent from the indoor unit allow the operating frequency
limitation and prevent abnormal high pressure.
Compressor will stop when ICT reaches 65
o
C
If the unit stops as such protection for 6 times, it can not resume running automatically and display
malfunction, it can resume by pressing ON/OFF.
11.11.3
Compressor over Heating Protection
The Discharging temperature is used as the compressor’s internal temperature. If the discharge
temperature rises above a certain level, the operating frequency upper limit is set to keep this
temperature from going up further.
Compressor will stop when CTT reaches certain value(see folowing table)
Compressor frequency(Hz)
CTT temperature (Stop compressor)
>50
110
o
C
[39,50]
105
o
C
<39
100
o
C
If the unit stops as such protection for 6 times, it can not resume running automatically and display
malfunction, it can resume by pressing ON/OFF.
11.11.4
Compressor over Current Protection
Detect an input current by the CT during the compressor is running, and set the frequency upper
limit from such input current. In case of heat pump model, this control is the upper limit control
function of the frequency which takes priority of the lower limit of four way valve activating
compensation.
Detail
Compressor will stop when AC current reaches 14.0A for continuesly 2.5s.
If the unit stops as such protection for 6 times, it can not resume running automatically and display
malfunction, it can resume by pressing ON/OFF.
