-
20
-
4.12 Protective control function
(1)
Frost prevention for indoor heat exchanger
(During cooling or dehumidifying)
(a)
Operating conditions
(i)
Indoor heat exchanger temperature (detected with Th2) is lower than 2.5ºC.
(ii)
3 minutes elapsed after the start of operation.
(b)
Detail of anti-frost operation
Compressor
OFF
Indoor fan
Protects the fan tap just before frost prevention control
Outdoor fan
OFF
4-way valve
Stop mode
(c)
Reset condition:
Indoor heat exchanger temperature (Th2) is higher than 8ºC.
(2)
Indoor fan motor protection
When the air conditioner is operating and the indoor fan motor is turned ON, if the indoor fan motor has operated at 300 rpm or
under for more than 30 seconds, the unit enters first in the stop mode and then stops the entire system.
TIMER light illuminates simultaneously and the RUN light flashing 6 times at each 8-second.
(3)
Three-minute forced operation
When the compressor begins operating the thermal operation is not effective for 3 minutes, so operation continues as is in the
operation mode. (After 3 minutes has passed the thermal operation is effective.)
However, stopping the compressor via a stop signal or protection control has priority.
¡
When the indoor heat exchanger
temperature is
>=
58˚C
Indoor heat exchanger temp. (˚C)
Compressor
Indoor heat exchanger temp. (˚C)
¡
When the indoor heat exchanger
temperature is
>=
62˚C
(4)
High-pressure control
The indoor heat exchanger sensor detection temperature controls the outdoor fan and compressor.
48
62
ON
OFF
(5)
Compressor overheat protection
If the discharge pipe temperature (sensed by Th6) exceeds the set temperature value, the compressor stops. If the temperature is 95ºC
or lower after a 3-minute delay, it starts again, but if this function is reactivated again within 60 minutes, it results in an abnormal stop.
Discharge pipe temperature (˚C)
Operation possible
Abnormal stop
125
95
Outdoor fan
<SRK20HG-S>
48
58
<SRK28HG-S>
48
58
<SRK40HG-S>
48
55
OFF
ON