McQuay AGZ026BS, Installation, Operation And Maintenance Manual

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18 AGZ 026B through 130B IOMM AGZ-5
Test coolant with a clean, accurate glycol solution hydrometer (similar to that found in
service stations) to determine the freezing point. Obtain percent glycol from the
freezing point table below. It is recommended that a minimum of 25% solution by
weight be used for protection against corrosion or that additional compatible inhibitors
be added.
Concentrations above 35 percent do not provide any additional burst protection and
should be carefully considered before using.
CAUTION
Do not use an automotive grade antifreeze. Industrial grade glycols must be used.
Automotive antifreeze contains inhibitors which will cause plating on the copper tubes
within the chiller evaporator. The type and handling of glycol used must be consistent
with local codes.
Table 7, Ethylene Glycol Factors for Models AGZ 026B to 070B
Freeze Point
% E.G.
o
F
o
C
Capacity Power Flow PD
10 26 -3.3 0.998 0.998 1.036 1.097
20 18 -7.8 0.993 0.997 1.060 1.226
30 7 -13.9 0.987 0.995 1.092 1.369
40 -7 -21.7 0.980 0.992 1.132 1.557
50 -28 -33.3 0.973 0.991 1.182 1.791
Table 8, Propylene Glycol Factors for Models AGZ 026B to 070B
Freeze Point
% P.G.
o
F
o
C
Capacity Power Flow PD
10 26 -3.3 0.995 0.997 1.016 1.100
20 19 -7.2 0.987 0.995 1.032 1.211
30 9 -12.8 0.978 0.992 1.057 1.380
40 -5 -20.6 0.964 0.987 1.092 1.703
50 -27 -32.8 0.952 0.983 1.140 2.251
Table 9, Ethylene Glycol Factors for Models AGZ 075B to 130B
Freeze Point
% E.G.
o
F
o
C
Capacity Power Flow PD
10 26 -3.3 0.994 0.998 1.038 1.101
20 18 -7.8 0.982 0.995 1.063 1.224
30 7 -13.9 0.970 0.992 1.095 1.358
40 -7 -21.7 0.955 0.987 1.134 1.536
50 -28 -33.3 0.939 0.983 1.184 1.755
Table 10, Propylene Glycol Factors for Models AGZ 075B to 130B
Freeze Point
% P.G.
o
F
o
C
Capacity Power Flow PD
10 26 -3.3 0.988 0.996 1.019 1.097
20 19 -7.2 0.972 0.992 1.035 1.201
30 9 -12.8 0.951 0.987 1.059 1.351
40 -5 -20.6 0.926 0.979 1.095 1.598
50 -27 -32.8 0.906 0.974 1.142 2.039