Unit installation
IOMM ACZ/AGZ-3  ACZ / AGZ-BM  19 
Evaporator Temperature Drop Factors 
Performance tables are based on a 10 degree F (5 degree C) temperature drop through the 
evaporator. Adjustment factors for applications with temperature ranges from 6 degree F to 16 
degree F (3.3 degree C to 8.9 degree C) are found in Table 12 and Table 13. Ranges outside these 
temperatures can affect the control system's capability to maintain acceptable control and must not 
be used. 
The maximum water temperature that can be circulated through the evaporator in a non-operating 
mode is 100°F (37.8°C). 
Fouling Factor 
Performance tables are based on water with a fouling factor of: 
)/0176.0(/0001.0
22
kWCmorBTUFhrft °×°×× per ARI 550/590-98. 
As fouling is increased, performance decreases. For performance at other than 0.0001 (0.0176) 
fouling factor, refer to Table 12 and Table 13. Foreign matter in the chilled water system will 
adversely affect the heat transfer capability of the evaporator and could increase the pressure drop 
and reduce the water flow. Maintain proper water treatment to provide optimum unit operation. 
Table 12, Capacity and Power Derates, Models AGZ 026 to 070 
Fouling Factor 
Chilled Water 
Delta T 
0.0001 (0.0176) 0.00025 (0.044) 0.00075 (0.132) 0.00175 (0.308) 
Altitude 
°F  °C  Cap. Power Cap. Power Cap. Power Cap. Power 
6  3.3  0.978 0.993 0.975 0.991 0.963 0.987 0.940 0.980 
8  4.4  0.989 0.996 0.986 0.994 0.973 0.990 0.950 0.983 
10  5.6  1.000 1.000 0.996 0.999 0.984 0.994 0.961 0.987 
12  6.7  1.009 1.003 1.005 1.001 0.993 0.997 0.969 0.990 
14  7.7  1.018 1.004 1.014 1.003 1.002 0.999 0.978 0.991 
Sea 
Level 
16  8.9  1.025 1.007 1.021 1.006 1.009 1.001 0.985 0.994 
6  3.3  0.977 1.001 0.973 1.000 0.961 0.996 0.938 0.989 
8  4.4  0.987 1.006 0.984 1.004 0.971 1.000 0.948 0.993 
10  5.6  0.998 1.009 0.995 1.007 0.982 1.003 0.959 0.996 
12  6.7  1.007 1.011 1.004 1.010 0.991 1.006 0.967 0.998 
14  7.7  1.014 1.014 1.011 1.013 0.998 1.009 0.974 1.001 
2000 feet 
16  8.9  1.022 1.016 1.018 1.014 1.005 1.010 0.981 1.003 
6  3.3  0.973 1.011 0.970 1.010 0.957 1.006 0.935 0.998 
8  4.4  0.984 1.014 0.980 1.013 0.968 1.009 0.945 1.001 
10  5.6  0.995 1.019 0.991 1.017 0.979 1.013 0.955 1.005 
12  6.7  1.004 1.021 1.000 1.020 0.987 1.016 0.964 1.008 
14  7.7  1.011 1.024 1.007 1.023 0.994 1.018 0.971 1.011 
4000 feet 
16  8.9  1.018 1.027 1.014 1.026 1.002 1.021 0.978 1.014 
6  3.3  0.969 1.021 0.966 1.020 0.954 1.016 0.931 1.008 
8  4.4  0.980 1.026 0.977 1.024 0.964 1.020 0.942 1.013 
10  5.6  0.989 1.029 0.986 1.027 0.973 1.023 0.950 1.015 
12  6.7  0.998 1.033 0.995 1.031 0.982 1.027 0.959 1.020 
14  7.7  1.007 1.036 1.004 1.034 0.991 1.030 0.967 1.022 
6000 feet 
16  8.9  1.014 1.037 1.011 1.036 0.998 1.031 0.974 1.024 
6  3.3  0.964 1.034 0.961 1.033 0.949 1.028 0.926 1.021 
8  4.4  0.975 1.037 0.971 1.036 0.959 1.031 0.936 1.024 
10  5.6  0.986 1.041 0.982 1.040 0.970 1.036 0.947 1.028 
12  6.7  0.995 1.044 0.991 1.043 0.979 1.038 0.955 1.031 
14  7.7  1.002 1.047 0.998 1.046 0.986 1.041 0.962 1.034 
8000 feet 
16  8.9  1.009 1.050 1.005 1.049 0.993 1.044 0.969 1.037 










