Mitsubishi Heavy Industries FDT28KXE6A Service Manual page 5

(4) Remote controller display during the operation stop
(a) "Centralized control ON" is displayed always on the LCD under the "Center/Remote" and "Center" modes during the
operation stop (Power ON). This is not displayed under the "Remote" mode.
(b) If this display is not shown under the "Center/Remote" mode, check if the indoor unit power switch is turned on or not.
(5) Hot start (Prevention of cold draft during heating)
At the startup of heating operation, at resetting the thermostat, during defrosting operation and at returning to heating, the
indoor fan is controlled by the indoor heat exchanger temperature (detected with Th
Fan
Lo
Indoor heat exchanger temp. (˚C)
Heat exchanger temp. 35
Compressor ON
Fan
Lo
Indoor heat exchanger temp. (˚C)
Note (1) Heating preparation is displayed during the hot start (when the compressor is operating and the indoor fan does not provide the set airflow volume).
(6) Hot keep
Hot keep control is performed at the start of the defrost control.
(a) Control
1) When the indoor heat exchanger temperature (detected with Th
changed to the lower tap at each setting.
2) During the hot keep operation, the louver horizontal control signal is transmitted.
(b) Ending condition
When the indoor fan is at the lower tap at each setting, it returns to the set airflow volume as the indoor heat exchanger
temperature rises to 45°C or higher.
(7) Fan control during the heating thermostat OFF
When the heating thermostat is turned OFF, the setting of the fan control is selectable with using the indoor function of wired
remote controller [Heating fan control].
(a) Low speed (Factory default)
If the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan operate at
the lower speed tap at each setting.
(b) Set airflow volume
Even if the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan
continues to run at the set airflow volume.
(c) Intermittent operation
If the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan operates at
the lower speed tap at each setting and, when the indoor heater exchanger temperature drops 25°C or lower, the indoor fan
stops for 5 minutes. Then the fan runs at the slow speed tap for 2 minutes, and the judgment is made by the thermostat.
(d) Stop
If the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan is turned
OFF. The same applies also when the remote controller sensor is effective.
Judgment by heating start thermostat
Thermostat OFF
Set airflow volume
35
or higher, or after 7 minutes
˚C
Normal condition/Set airflow volume
Compressor OFF
Set airflow volume
（1）
35 45
-R) to prevent the cold draft.
I
Thermostat ON
Lo
Fan
OFF
25
Indoor heat exchanger temp. (˚C)
Heat exchanger temp. 35
˚C
Defrosting start
Lo
Fan
OFF
25
Indoor heat exchanger temp. (˚C)
-R1 or R2) drops to 35°C or lower, indoor fan is
I
3
– –
Set airflow volume
35
or higher, or after 7 minutes
End of defrosting
Set airflow volume
35 45