Mitsubishi SRK 25ZS-W, Technical Manual

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74
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'18 • SRK-T-250
'09•SRK-DB-087D
(e) Cooling low outdoor air temperature protective control
(i) Operating conditions
(ii) Detail of operation
C D A B
OFF
E F
Upper 2
Lower 2
ON
ON
Upper 3
Lower 3 ON
Upper 1
Lower 1
Outdoor air temperature (°C)
(iii) Reset conditions
(f ) Heating high pressure control
(i) Purpose
(ii) Detector
(iii) Detail of operation
A
B C D
Indoor heat exchanger temperature(°C)
4rps (1) 8rps (2)
8rps
(2)
4rps
(1)
0rps
After lapse of 20 sec. or over
(3)
After lapse of 20 sec. or over (3)
After lapse of 20 sec. or over
(3)
lower limit
speed 30(27) rps
(Example)
Compressor
speed
Temperature list
Models SRK20, 25, 35
A B C D
RPSmin < 50
50 <
= RPSmin < 92
92 <
=
<
=
RPSmin 115
First time
After the
second times
Outdoor air temperature (˚C)
A B C D E F
(Models SRK20-35)
First time
After the
second times
Outdoor air temperature (˚C)
A B C D
(Model SRK50)
9
16 19
11
Note (1) Value in ( ) are for the model SRK50.
When the outdoor air temperature (TH2) is 22°C or lower continues for 20 seconds while the compressor speed is other than 0 rps.
Compressor speed: Upper/lower limit (rps)
Lower 3 Upper 2 Lower 2
Lower 1
Upper 1
Range A Range B
Upper 3
26 24
Outdoor air temperature (
Υ
)
50 50 44 30 50
Range A
Range B
−
50 44
60
60 27
Release
Release
−
SRK20, 25, 35
SRK50
1) It controls the upper and lower limit values for the compressor speed according to the following table.
2) It checks the outdoor temperature (TH2) once every hour to judge the operation range.
When either of the following condition is satisfied.
1) The outdoor air temperature (TH2) is D°C or higher.
2) The compressor speed is 0 rps.
fan speed fan
When the indoor heat exchanger temperature is in the range of A-B °C, if the compressor speed is been maintained and the operation has continued for more
than 20 seconds at the same speed, it returns to the normal heating operation.
B - C
C - D
47
47.5
47.5 - 39
52
55
55 - 40
54
57
57 - 42
58
61
61
)
'09•SRK-DB-087D
(g) Heating overload protective control
(i) Indoor fan speed
1) Operating conditions
2) Detail of operation
3) Reset conditions
(ii) Outdoor unit side
1) Operating conditions
2) Detail of operation
3) Reset conditions
(i) Operating conditions:
(ii) Detail of operation:
(h) Heating low outdoor temperature protective control
(iii) Reset conditions:
-10 -8 -2 2
Lower limit 45 rps
Lower limit 40 rps
Normal operation
Outdoor air temperature(°C
10 11 19 20
Normal operation
Protective control ON1
Protective control ON2
Outdoor air temperature(°C)
21 22
Normal operation
Protective
control
Outdoor air temperature(°C)
• Model SRK50
• Model SRK50
• Models SRK20 ~ 35
• Models SRK20, 25, 35
(i)
ࠉ
Operating conditions: When the outdoor air temperature (TH2) is lower than 4ºC or 13ºC or higher continues for 30
seconds while the compressor command speed is other than 0 rps.
(ii)
ࠉ
Detail of operation: The lower limit compressor command speed is change as shown in the figure belo.
Lower limit 29 rps
Normal operation
4 6
Outdoor air temperature(°C)
Model SRK50
A B C D
RPSmin < 35
40 <
= RPSmin < 80
80 <
= RPSmin < 95
95 <
= RPSmin < 115
115 <
= RPSmin
49
52
43
52 - 48.1
48.1 - 43
54
57
46
57 - 52.2
52.2 - 46
55
58
47
58 - 53.2
53.2 - 47
55.5
62
35 <
= RPSmin < 40
49 - 52 54 - 57 55 - 58 55.5 - 62
50.5
62 - 56
56 - 50.5
a)
b)
c)
d)
The lower limit of compressor speed is set to 40 rps and even if the calculated result becomes lower than that after
fuzzy calculation, the speed is kept to 40 rps. However, when the thermostat OFF, the speed is reduced to 0 rps.
fan speed is
rps.
1) Operating conditions
2) Detail of operation
When the outdoor air temperature (TH2) is 11ºC or higher continues for 30 seconds while the compressor speed other than 0 rps.
a)
b)
c)
d)
Taking the upper limit of compressor speed range at 78 rps, if the output speed obtained with the fuzzy calculation
exceeds the upper limit, the upper limit value is maintained.
The lower limit of compressor speed is set to 30 rps and even if the calculated result becomes lower than that after
fuzzy calculation, the speed is kept to 30 rps. However, when the thermostat OFF, the speed is reduced to 0 prs.
rps.
3) Reset conditions
1)
2)
30
Protective
control
ON1
ON2
Item
Compressor speed
Low limit
30 rps
30 rps
Upper limit
78 rps
51 rps
The indoor fan speed is stepped up by 1 speed step. (Upper limit 9th speed)
When the outdoor air temperature (TH2) is 17°C or higher continues for 30 seconds while the compressor speed other than 0 rps.
When the outdoor air temperature (TH2) is 22°C or higher continues for 30 seconds while the compressor speed other than 0 rps.
The outdoor air temperature (TH2) is lower than 16°C.
The outdoor air temperature (TH2) is lower than 21°C.
The outdoor air temperature (TH2) is lower than 10°C.
Outdoor fan speed
It depends on compressor speed
2nd
Taking the upper limit of compressor speed at 60 rps, if the output speed obtained with the fuzzy calculation
exceeds the upper limit, the upper limit value is maintained.