Trane City RTSF050 Installation Operation & Maintenance page 19

Cooling device bypass – Figure 3
Cooling device bypass is also a valid control method if
the chiller temperature requirements can be maintained.
Advantage:
Sound power levels
• Excellent control by maintaining constant water flow
through the condenser.
Discharge
Disadvantage:
• Higher cost because of the dedicated pump required for
Measurement conditions:
each chiller if condenser pressure is the control signal.
Measurements taken in a room adjacent to the room containing the FWD, at the outlet of the rectangular duct (1.5 m
long) fixed to its discharge opening.
Figure 3
Fan
Unit speed
1
FWD 08 2
1
3
2A
1
FWD 10 2
3
1
7
FWD 12 2
3
1
FWD 14 2
3
1
FWD 20 2
3
Intake
Measurement conditions:
Measurements taken at the horizontal air intake.
Fan
Unit speed
1
FWD 08 2
3
1
FWD 10 2
3
1
FWD 12 2
3
1
FWD 14 2
3
1
FWD 20 2
3
UNT-PRC002-GB
RLC-SVX023A
3
Power level in dB(A), per Hz frequency band
125 250
55 50
57 54
4
58 57
CO
57 51
58 54
60 58
57 51
CDS
58 54
60 58
56 62
61 66
CI
63 69
5A
57 63
EO
61 66
63 69
6
EVP
EI
Power level in dB(A), per Hz frequency band
125 250
56 55
63 62
66 65
62 58
66 63
70 67
62 58
66 63
70 67
66 65
73 72
78 76
68 72
76 76
78 79
Condenser water pump with variable frequency drive –
Figure 4
Advantages:
• Pumping cost can be reduced. Good cooling device
temperature control.
• Relatively low first cost.
Disadvantage:
• Increased rate of fouling due to lower water velocity in
the condenser.
Figure 4
500 1000
42 37
47 40
50 42
7
45 42
48 45
50 48
45 42
48 45
50 48
50 48
4
55 53
58 56
51 49
55 53
58 56
500 1000
1 = Electric valve actuator
55 53
60 2A = 3-way valve or 2 butterfly valves 60
63 62
2B = 2 butterfly valves
55 58
60 62
3 = RTSF controller
63 65
4 = Refrigerant pressure line
55 58
60 62
5A = Condenser water pump
63 65
65 65
5B = Condenser water pump with VFD
69 71
6 = To/from cooling load
73 75
64 64
7 = To/from cooling device
68 71
71 8 = Electric controller 74
EI = Evaporator Inlet
EO = Evaporator Outlet
CI = Condenser Inlet
CO = Condenser Outlet
Installation - Mechanical
CO
2000 4000 8000
37 31 30
30 38 40
32 40 43
34 33 28
38 39 35
40 42 39
34 33 28
38 39 35
CI
5B
40 42 39
39 38 36
47 46 45
50 50 49
40 39 37
8
47 46 45
50 50 49
EO
EI
2000 4000 8000
46 45 42
53 53 53
56 55 57
51 48 44
56 55 52
59 59 57
51 48 44
56 55 52
59 59 57
57 50 46
64 59 57
69 64 63
56 52 50
65 61 61
69 66 66
Overall power
dB(A)
46
50
53
CDS
48
51
54
48
51
54
56
60
4
63
57
60
63
EVP
Overall power
dB(A)
57
64
67
61
66
69
61
66
69
68
74
78
69
75
78
11
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