Mitsubishi SRK 25ZS-W, Technical Manual

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71
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'18 • SRK-T-250
'09•SRK-DB-087D
(b)
(i)
(ii)
(iii)
(c)
(d)
27.5
25.5
18.0
18
30
(17) Outline of cooling operation
(a)
ࠉ
Operation of major functional components in cooling mode
(d) Countermeasure for excessive temperature rise
If it feels excessive temperature rise in heating operation, setting temperature can be lower.
ON OFF OFF
OFF OFF OFF
ON
OFF
(few minutes ON)
OFF
(few minutes ON)
ON ON OFF
Thermostat ON Thermostat OFF Failure
Cooling
Compressor
Indoor fan motor
Outdoor fan motor
4-way valve
(19)
ࠉ
Outline of automatic operation
(a) Determination of operation mode
Heating
Dehumidifying
Cooling
Indoor air temperature (˚C)
Outdoor air temperature (˚C)
Signals of wireless remote control (Display)
–6 –5 –4 –3 –2 –1
±
0 +1 +2 +3 +4 +5 +6
Setting
temperature
Cooling
Dehumidifying
Heating
A
When both the indoor and the outdoor air temperatures are in the range “A”, cooling or heating is switched depending on
the difference between the setting temperature and the indoor air temperature.
When the operation mode has been judged following the change of setting temperature with the remote control, the hourly j-
udgment of operation mode is cancelled.
(e) When the unit is operated automatically with the wired remote control connected, the cooling operation is controlled according to
the display temperatures while the setting temperature is compensated by 1 during dehumidifying or by 2 during heating.
(b) Detail of control in each mode (Pattern)
(i) Fuzzy operation
15-98rps
15-98rps
15-80rps
15-70rps
SRK35
20-100rps
20-100rps
20-82rps
20-66rps
SRK50
15-74rps
15-74rps
15-60rps
15-48rps
SRK25
15-66rps
15-66rps
15-52rps
15-42rps
15-46rps 20-40rps 15-38rps 15-34rps
SRK20
Model
Fan speed
Auto
MED
ULO
HI
LO
Heating
Cooling
SP: Setting temperature
SP
Indoor air
temperature (˚C)
28
Outdoor air temperature (˚C)
(b) Operation mode is changes when keep cooling and heating thermostat off 20 minutes and be satisfied with following conditions.
If the setting temperature is changed with the remote control, the operation mode is judged immediately.
(c) When the unit is started again within one hour after the stop of automatic operation or when the automatic operation is
selected during heating, cooling or DRY mode, the unit is operated in the previous operation mode.
(d) Setting temperature can be adjusted within the following range. There is the relationship as shown below between the signals
of the wireless remote control and the setting temperature.
(e) When the unit is operated automatically with the wired remote control, the cooling operation is controlled according to the
display temperatures while the setting temperature is compensated by
＋
2
℃
during heating.
※
It can not be changed to heating mode if outdoor air temperature is 28
℃
or higher.
Heating
SP: Setting temperature
Indoor air temperature
－
Setting temperature (˚C)
Keep operation
mode
Cooling
Signals of wireless remote control (Display)
18 19 20 21 22 23 24 25 26 27 28 29 30
18 19 20 21 22 23
24
25 26 27 28 29 30
20 21 22 23 24 25
26
27 28 29 30 31 32
Setting
temperature
Cooling
Heating
SP
＋
1
SP
－
1
Unit :
℃
(18) Outline of dehumidifying (DRY) operation
The purpose is "Dehumidification", and not to control the humidity to the target condition.
Indoor/outdoor unit control the operation condition to reduce the humidity, and also prevent over cooling.
(i) Indoor unit fan speed and compressor are controlled by the area which is selected by the temperature difference.
Indoor unit fan speed
Area
D C B A
Me speed
Indoor unit
fan speed ULo(Lo) speed
Stop
Limited
（
Lower than
normal cooling operation
）
Compressor Limited
speed Minimum
（
Lower than the speed in”Area A”
）
Stop
Setting temperature
Difference between set temperature and indoor air temperature
When the outdoor air temperature and room temperature are low in cooling operation, indoor unit can not operate cooling mode,
and DRY mode. In this case, the unit operates in heating mode to rise the indoor air temperature and after that start DRY mode.
(a) Purpose of DRY mode
(b) Outline of control
(ii) The indoor unit checks the current area by every 5 minutes, and operates by the next checking.
(c) Other
Operation mode is determined by indoor air temperature and outdoor air temperature as following.
(a) Determination of operation mode