SERVICE MANUAL
R
−
410A Ductless Split System: DLF4(A/H), DLC4(A/H)
46
421 08 9204 00
heating
(12) Drying Function
You may start or stop the dry function under the cooling and dry
modes. Automatic heating and air modes do not support the dry
function).
(13) Memory function
when interrupting the power supply
Memory content: mode, swing function, light, set temperature
and blower speed.
After power is interrupted, the machine will start according to the
content of the memory automatically. If the last remote control
command has not set a timed function, the system will
remember the last remote control command and operate
accordingly. If the last remote control command has set a timed
function and the power supply is interrupted before the time
expires, the system will remember the timed function of the last
remote control command, the timed time will be recounted from
power on. If the last remote control command has set a timed
function, the time is up and the system is started or stopped
according to the set time when the power supply is interrupted,
the system will remember the operation status before the power
supply was interrupted, and not carry out the timed action; The
time clock will not be remembered.
Detection of Temperature Sensor Malfunction
(1) Indoor Temperature Sensor
Malfunctions of the temperature sensor can be detected at any
time.
(2) Indoor Pipe Temperature Sensor
During defrost, a temperature sensor malfunction will not be
detected. Five minutes after finishing defrost, the system will
again begin to detect temperature sensor malfunctions. At all
other times, a temperature sensor malfunction will be detected.
1. When a short
−
circuit occurs to the temperature sensor for 30
seconds: The temperature sensor overheats. In this case to
protect the system, the entire unit will stop. At the same time, the
temperature protection and temperature sensor malfunction will
be shown.
2. When an open circuit of the temperature sensor occurs for
30s: The unit will stop and the temperature sensor malfunction
will be displayed
Frequency Control
When starting the compressor, or when conditions have varied
due to the changes in the room, the frequency must be initialized
according to the
D
D value of the indoor unit and the Q value of
the indoor unit. Q value: Indoor unit output determined from
indoor unit volume, air flow rate and other factors.
Compressor Protection Function
When turning the compressor from OFF to ON, the system will
ramp the frequency up from a lower starting limit to protect the
compressor.
Figure 18
-
Compressor Frequency (When the compressor
is turned off, it cannot be turned back on for 3 minutes ((ex-
cept after defrost)).
Discharge Pipe Control
The discharge pipe temperature is used as the compressor’s
internal temperature. If the discharge pipe temperature rises
above a certain level, the operating frequency upper limit is set
to keep this temperature from going up further.
Input Current Control
Detects an input current with the current transformer as the
compressor is running, and sets the upper frequency limit from
the input current.
In the case of a heat pump, this control is the upper limit control
function of the frequency, which takes priority over the lower limit
of four way valves activation compensation.
Freeze
−
up Protection Control
During cooling operation, the signals being sent from the indoor
unit allow operating frequency limitation and then prevent
freezing of the indoor heat exchanger.
Heating Peak
−
cut Control: Heat
−
Pump Only
During heating operation, the signals being sent from the indoor
unit allow operating frequency limitation and prevent abnormally
high pressure.
Defrost Control: Heat Pump Only
Defrosting is carried out by the cooling cycle (reverse cycle). The
defrost time must be complete or the outdoor heat exchanger
temperature must be more than its preset value when finishing.
Conditions for Starting Defrost
The starting conditions must be determined by the outdoor air
temperature and heat exchanger temperature. When the system
is in heating operation, 6 minutes after the compressor is started,
and more than 44 minutes of accumulated time has passed
since the start of the operation or end of defrost.
Conditions for Canceling Defrost
The heat exchanger temperature must be between (39
°
F
−
72
°
F)
Fan Control
Fan control is carried out according to the following priority.
1. Fan ON control for electric component cooling fan
2. Fan control when defrosting
3. Fan OFF delay when stopped
4. ON/OFF control in cooling operation
5. Speed control when frequency adjustment function is working
6. Fan control in forced operation
7. Fan control in indoor/outdoor unit silent operation
8. Fan control in powerful mode
9. Fan control in normal operation
Fan OFF Control when Stopped
* Fan OFF delay for 60 seconds must be made when the
compressor is stopped.
Speed Control in indoor/outdoor unit silent operation
1. When in Cooling Operation
When the outdoor air temperature is lower than 99
°
F, the speed
tap must be set to Low.
2. When in Heating Operation
When the outdoor air temperature is higher than 39
°
F, the speed
tap must be set to Low (only for heat pump model).
