Operation Control Function By The Outdoor Control; Defrosting Operation; Cooling Overload Protective Control - Mitsubishi Heavy Industries FDTC40ZSXVF Technical Manual

4-way valve
*It can be set the indoor fan motor off or the heating thermostat OFF with connecting a wired remote control.
In the case, indoor air temperature is detected by sensor on the wired remote control.
(b) Details of control at each operation mode (pattern)
(ii) Hot keep operation
(i) Fuzzy operation
11.4 Operation control function by the indoor control
During the heating operation, the indoor fan speed can be controlled based on the temperature of the indoor heat
exchanger (Th2) to prevent blowing out of cold air.
Models SRC40-60
(1) Defrost operation
Fan speed
(ii) Hot keep operation
During the heating operation, the indoor fan speed can be controlled based on the temperature of the indoor heat
exchanger (Th2) to prevent blowing out of cold air.
(1) Defrost operation
0
5)
Defrost operation
start
-20 -15 -10 -5
(b) Frost prevention control
Outdoor air temperature (℃)
(i) Operating conditions
1)
5)
2)
(ii) Detail of anti-frost operation
Item
Lower limit of compressor command speed
Indoor fan
Outdoor fan
4-way valve
(iii) Reset conditions
1)
2)

(2) Cooling overload protective control

(a) Operating conditions
When the outdoor air temperature (TH2) has become continuously for 30 seconds at 41°C or more, or
47ºC or more with the compressor running, the lower limit speed of compressor is brought up.
Outdoor air temperature
Lower limit speed
(b) Detail of operation
1) The outdoor fan is stepped up by 3 speed step. [Upper limit 8 th speed.]
2) The lower limit of compressor speed is set to 30 or 40 rps.
However, when the thermo OFF, the speed is reduced to 0 rps.
(c) Reset conditions
12-78rps
MED
12-42rps
LO
ON
12-30rps
ULO
12-42rps
ECO
Model
SRK20ZSX-S
12-78rps
Auto
12-78rps
HI
12-78rps
MED
LO 12-42rps
12-30rps
ULO
12-42rps
ECO
Models SRK50, 60
0
In case satisfied all of following conditions.
-5
• Connect compressor speed 0 rps 10 times or more.
• Satisfy 1), 2) and 3) conditions above.
• Outdoor air temperature is 3°C or less.
-10
-15
-20
0 5 10 -20
In case satisfied all of following conditions.
• Connect compressor speed 0 rps 10 times or more.
• Satisfy 1), 2) and 3) conditions above.
Indoor heat exchanger
• Outdoor air temperature is 3°C or less.
temperature
Depends on compressor speed
¡Defrost operation
Heating operation
Depends on an operation condition, the time can be longer than 7 minutes.
ON2
ON1
OFF
37 38 40 41
Outdoor air temperature (°C)
12-86rps
(few minutes ON)
12-50rps
ON
12-30rps
12-50rps
SRK25ZSX-S
12-86rps
12-86rps
12-86rps
12-50rps
12-30rps
12-50rps
Defrost operation
start
-15 -10 -5 0
Outdoor air temperature (℃)
5°C or lower 2.5°C or lower
(models SRK50, 60 : 25 rps)
Keep the fan speed before
frost prevention control
2.5–5
5–8
Max. 18 minutes.
ON3
46 47
105
- -
12-98rps 12-106rps
12-66rps OFF 12-78rps
(3 minutes ON)
12-30rps 12-38rps
12-66rps 12-78rps
SRK35ZSX-S SRK50ZSX-S
12-98rps 12-106rps
12-98rps 12-106rps
12-98rps 12-106rps
12-66rps 12-78rps
12-30rps 12-38rps
12-66rps 12-78rps
5 10
compressor
speed
Lower
limit
speed
0 rps
Indoor heat exchanger
2~7 minutes
Hot keep operation
ON1
OFF
40 41 46 47
Outdoor air temperature (°C)
12-120rps
12-90rps
12-38rps
12-90rps
'17 • PAC-T-256
SRK60ZSX-S
12-120rps
12-120rps
12-120rps
12-90rps
12-38rps
12-90rps
'09•SRK-DB-087D
2.5 5 8
temperature (°C)
ON2