Trane CONQUEST CGAX Series Installation Operation & Maintenance page 49

Refrigerant Piping
The compressor suction and discharge connections
and piping are copper clad steel for easy brazing. In
most instances, piping may be reused. If piping is not
Sound power levels
reusable, order the correct service parts. Cut all tubing
with a tubing cutter to prevent copper filings from
Discharge
entering the system. Cut the tubing in a straight length
of pipe after the compressor connection has been
Measurement conditions:
unsweated. The line can then be reinstalled using a slip
Measurements taken in a room adjacent to the room containing the FWD, at the outlet of the rectangular duct (1.5 m coupling and brazing.
long) fixed to its discharge opening.
Note: The compressor suction line configuration must
not be changed in any way. Changing compressor
Fan
suction line configuration will compromise proper oil
Unit speed
return to the compressor(s).
1
FWD 08 2
Compressor Electrical Terminal Box 3
1
FWD 10 2
Be sure to protect the terminal box when unbrazing or
3
brazing compressor refrigerant piping connections
1
FWD 12 2
3
Compressor Crankcase Heaters
1
FWD 14 2
Compressor crankcase heaters must be energized at
3
1
least eight hours before starting the chiller. This is
FWD 20 2
required to boil refrigerant out of the oil before startup.
3
Ambient temperature is not a factor and the crankcase
heaters must always be energized prior to startup.
Intake
Condenser Maintenance
Measurement conditions:
Measurements taken at the horizontal air intake.
Condenser Coil Cleaning
Clean the condenser coils at least once a year or more
Fan
Unit speed
frequently if the unit is in a "dirty" environment. A clean
1
condenser coil will help to maintain chiller operating
FWD 08 2
efficiency. Follow the detergent manufacturer's
3
instructions to avoid damaging the condenser coils. 1
FWD 10 2
Black epoxy coil protection (option on heat pump units)
3
1
It is recommended to clean the coils at unit start-up and
FWD 12 2
regularly to obtain optimum protection and life span of
3
the condenser coils. To clean the condenser coils use a
1
FWD 14 2
soft brush and a sprayer such as a garden pump type or
3
a high pressure type. A high quality detergent such as
1
Trane Coil Cleaner is recommended.
FWD 20 2
3
Note: If detergent mixture is strongly alkaline (pH value
greater than 8 .5), an inhibitor must be added.
CG-SVX027E-GB UNT-PRC002-GB
Power level in dB(A), per Hz frequency band
125 250 500
55 50 42
57 54 47
58 57 50
57 51 45
58 54 48
60 58 50
57 51 45
58 54 48
60 58 50
56 62 50
61 66 55
63 69 58
57 63 51
61 66 55
63 69 58
Power level in dB(A), per Hz frequency band
125 250 500
56 55 55
63 62 60
66 65 63
62 58 55
66 63 60
70 67 63
62 58 55
66 63 60
70 67 63
66 65 65
73 72 69
78 76 73
68 72 64
76 76 68
78 79 71
Evaporator Maintenance
The Trane Model CGAX liquid chiller uses a brazed plate
heat paddle (BPHE) evaporator with factory installed
flow switch that is positioned in the evaporator water
pipe. The evaporator inlet also includes a water strainer
that must be kept in place to keep debris out of the
evaporator.
Note: Strainer maintenance is critical to proper
operation and reliability. Any particles larger than
1.6 mm entering the BPHE evaporator may cause the
evaporator to fail, requiring replacement.
Acceptable BPHE evaporator water flow rate is 1.4 to 1000 2000
37 37
4.2 l/ min per nominal unit kW capacity. To maintain
40 30
12-7°C in/out chilled water temperatures, the nominal
42 32
water flow rate is 2.8 l/min per cooling kW. Minimum
42 34
45 38
water flow rate must be maintained to avoid laminar
48 40
flow, potential evaporator freezing, scaling and poor
42 34
temperature control. Maximum water flow is 6 m/s. Flow
45 38
48 40
rates greater than this will cause excessive erosion. The
48 39
BPHE evaporator is difficult to clean should it become
53 47
plugged with debris. Indications of a plugged BPHE
56 50
evaporator include "wet" suction due to lack of heat
49 40
53 47
exchange, loss of superheat control, discharge superheat
56 50
less than 35°C, compressor oil dilution and/or starvation
and premature compressor failure.
Evaporator replacement
If the CGAX evaporator requires replacement, it is very
important that the new evaporator be replaced correctly
and with the correct refrigerant and water piping
1000 2000
connections. The refrigerant inlet/ liquid connection is at
53 46
60 53
the bottom of the evaporator and the refrigerant outlet/
62 56
suction connection is at the top of the evaporator and
58 51
both are on the same side. Pay particular attention to
62 56
evaporators with dual circuits. Avoid cross-circuiting 65 59
58 51
when installing the new evaporator.
62 56
65 59
65 57
71 64
75 69
64 56
71 65
74 69
Maintenance
Overall power
4000 8000 dB(A)
31 30 46
38 40 50
40 43 53
33 28 48
39 35 51
42 39 54
33 28 48
39 35 51
42 39 54
38 36 56
46 45 60
50 49 63
39 37 57
46 45 60
50 49 63
Overall power
4000 8000 dB(A)
45 42 57
53 53 64
55 57 67
48 44 61
55 52 66
59 57 69
48 44 61
55 52 66
59 57 69
50 46 68
59 57 74
64 63 78
52 50 69
61 61 75
66 66 78
11 49