Carrier 38VMA Series, Service Manual, Page: 28 / 112

Table 13
- Heating Compressor Control (38VMA144HDS)
Capacity
QHr
Frequency
Capacity
QHr
Frequency
Capacity
QHr
Frequency
38VMA144(1) 38VMA144(2) 38VMA144(1) 38VMA144(2) 38VMA144(1) 38VMA144(2)
1 20Hz 20 60Hz 42 + 40 39 73 + 71
2 20Hz 21 62Hz 44 + 42 40 74 + 72
3 21Hz 22 64Hz 46 + 44 41 75 + 73
4 22Hz 23 68Hz 48 + 45 42 76 + 74
5 23Hz 24 70Hz 48 + 46 43 78 + 76
6 24Hz 25 72Hz 52 + 46 44 80 + 78
7 26Hz 26 74Hz 52 + 48 45 81 + 79
8 28Hz 27 76Hz 54 + 52 46 82 + 80
9 32Hz 28 56 + 54 47 83 + 81
10 36Hz 29 58 + 56 48 84 + 82
11 39Hz 30 60 + 58 49 85 + 83
12 42Hz 31 62 + 60 50 86 + 84
13 44Hz 32 63 + 61 51 87 + 85
14 46Hz 33 64 + 62 52 88 + 86
15 48Hz 34 66 + 64 53 89 + 87
16 52Hz 35 67 + 65 54 90 + 88
17 54Hz 36 68 + 66 55 92 + 90
18 56Hz 37 70 + 68 56 92 + 90
19 58Hz 38 72 + 70
NOTES:
Compressors are operated in the order of descending priorities.
Compressors may operate in a pattern other than those listed in above tables subject to the operating conditions.
3. Electronic Expansion Valve Control
a. Cooling Electronic Expansion Valve Control
Electronic Expansion Valve EXV A EXV B EXV C
Normal control 350P 350P PI control
b. Heating Electronic Expansion Valve Control
Table 14 - EXV A, EXV B (38VMA072, 096, 120HDS)
Capacity 1—15 16—30 31—48
Initial pulse step 256P 352P 480P
Normal control
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