Mitsubishi SRK25ZSP-W Service Manual page 11

(c) Frost prevention control
(i) Operating conditions
1)
2)
(ii) Detail of anti-frost operation
Indoor heat exchanger
temperature
Item
Lower limit of compressor speed
Indoor fan
Outdoor fan
4-way valve
(iii) Reset conditions
1)
2)
(d) Cooling overload protective control
(c) Cooling overload protective control
(i) Operating conditions
(i) Operating conditions:
When the outdoor air temperature (TH2) has become continuously for 30 seconds at 41ºC or more, or 47ºC or more
with the compressor running, the lower limit speed of compressor is brought up.
Item
Item
Outdoor air temperature
Outdoor air temperature
Lower limit speed
Lower limit speed
(ii) Detail of operation
(ii) Detail of operation
1) The outdoor fan is stepped up by 3 speed step. (Upper limit; 8th speed.)
1)
2) The lower limit of compressor speed is set to 30 or 45(model SRK45 : 27 or 35) rps. However, when the thermo
2) The lower limit of compressor command speed is set to 30 or 40 (model SRK50 : 29) rps and even if the calculated
OFF, the speed is reduced to 0 rps.
result becomes lower than that after fuzzy calculation, the speed is kept to 30 or 40 (model SRK50 : 29) rps. Howev-
(iii) Reset conditions
er, when the thermo OFF, the speed is reduced to 0 rps.
When either of the following condition is satisfied.
(iii) Reset conditions:
1) The outdoor air temperature is lower than 40ºC.
1)
2) The compressor speed is 0 rps.
2)
(e) Cooling high pressure control
(d) Cooling high pressure control
(i) Purpose
(i) Purpose:
Prevents anomalous high pressure operation during cooling.
(ii) Detector:
(ii) Detector
(iii) Detail of operation:
Outdoor heat exchanger sensor (TH1)
(Example) Fuzzy
(iii) Detail of operation
(Example) Fuzzy
A
5°C or lower
22rps (SRK45 : 23 rps)
compressor
more, or 47ºC or more (model SRK50 : 41ºC or more) with the compressor running, the lower
limit
Model
Model
SRK25, 35ZSP-W
SRK20~35ZJ-S
41°C or more
30 rps
After lapse of 30 sec. or over
After lapse of 30 sec. or over
After lapse of 20 sec. or over
After lapse of 30 sec. or over
After lapse of 20 sec. or over
After lapse of 20 sec. or over
53
Outdoor heat exchanger temperature (°C)
Outdoor heat exchanger temperature(°C)
9
-
compressor
2.5°C or lower
-
-
SRK50ZJ-S
47°C or more 41°C or more
41°C or more
45 rps
29 rps
(3) 6rps (1)
6rps
(3)
lower limit
(3)
(3)
speed 30 (model SRK50 : 29) rps
(3)
(3)
58
B
-
'09•SRK-DB-087D
'18 • SRK-SM-259
speed
Lower
limit
speed
0 rps
2.5 5
Indoor heat exchanger
temperature (ºC)
SRK45ZSP-W
47°C or more
27 rps 35 rps
(1)
8rps (1)
8rps (1)
0rps
0rps
63
C
8