(4) Heating high pressure control
(a) Models SCM71, 80
(i) Starting condition:
When the indoor heat exchanger temperature (Th2) has risen to a specified temperature while
the compressor is turned on.
(ii) Compressor command speed is controlled according to the zones of indoor heat exchanger tem-
perature as shown by the following table.
Th2 < P1
P1
<=
Th2 < P2
P2
<=
Th2 < P3
P3
<=
Th2
Protection control speed (NP)
Normal
Retention
NP–4rps
NP–8rps
Sampling time (s)
Normal
20
20
20
Th2
NP
P1
P2
P3
10
<=
NP < 90
45
52
57
90
<=
NP < 100
45 – 44.5
52 – 49.5
57 – 54
100
<=
NP < 110
44.5 – 44
49.5 – 47.5
54 – 51
110
<=
NP < 120
44 – 43
47.5 – 45
51 – 48
120
<=
NP
43
45
48
• Models SCM71, 80
Unit: °C
(a) Operating conditions:
When the outdoor air temperature (Tho-A) is 22°C or lower continues for 20 seconds while
compressor command speed is other than 0 rps.
(b) Detail of operation:
(i)
The lower limit of compressor command speed is set to B or D rps and even if the speed becomes lower than B or D
rps, the speed is kept to B or D rps. However, when the thermo becomes OFF, the speed is reduced to 0 rps.
(ii)
The upper limit of compressor command speed is set to A or C rps, the speed is kept to A or C rps.
(c) Reset conditions:
When the either of the following conditions is satisfied
(i)
When the outdoor air temperature (Tho-A) becomes 25°C or higher.
(ii)
When the compressor command speed is 0rps.
(3) Cooling low outdoor temperature protective control
22
25
OFF
0
3
Upper limit C rps
Lower limit D rps
ON
ON
Upper limit A rps
Lower limit B rps
Outdoor air temperature(°C)
Model
A
B
C
D
75 rps
30 rps
60 rps
40 rps
SCM80ZM-S1
75 rps
30 rps
60 rps
40 rps
SCM71ZM-S1
Values of A ~ D
-
196
-
'17 • SCM-T-225
