McQuay AGZ 030AM, Руководство по эксплуатации продукта

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14 AGZ 030A through 065A Product Manual AGZ-2
Application Adjustment Factors
Ethylene and Propylene Glycol Factors
AGZ units can operate with a leaving chilled fluid temperature range of 20°F (-6°C) to 50°F (10°C).
A glycol solution is required when leaving chilled fluid temperature is below 40°F (4.6°C). The use
of glycol will reduce the performance of the unit depending on concentration.
Altitude Correction Factors
Performance tables are based at sea level. Elevations other than sea level affect the performance of the
unit. The decreased air density will reduce condenser capacity consequently reducing the unit's
performance. For performance at elevations other than sea level refer to Table 3.
Evaporator Temperature Drop Factors
Performance tables are based on a 10°F (5°C) temperature drop through the evaporator. Adjustment
factors for applications with temperature ranges from 6°F to 16°F (3.3°C to 8.9°C) are in Table 3.
Temperature drops outside this 6°F to 16°F (3.3°C to 8.9°C) range may affect the control system's
capability to maintain acceptable control and are not recommended.
The maximum water temperature that can be circulated through the evaporator in a non-operating
mode is 100°F (37.8°C).
Table 1, Ethylene Glycol
% Freeze Point
E.G. °F °C Capacity Power Flow PD
10 26 -3 0.991 0.996 1.013 1.070
20 18 -8 0.982 0.992 1.040 1.129
30 7 -14 0.972 0.986 1.074 1.181
40 -7 -22 0.961 0.976 1.121 1.263
50 -28 -33 0.946 0.966 1.178 1.308
Table 2, Propylene Glycol
% Freeze Point
P.G. °F °C Capacity Power Flow PD
10 26 -3 0.987 0.992 1.010 1.068
20 19 -7 0.975 0.985 1.028 1.147
30 9 -13 0.962 0.978 1.050 1.248
40 -5 -21 0.946 0.971 1.078 1.366
50 -27 -33 0.929 0.965 1.116 1.481
NOTE: Ethylene and propylene glycol ratings are outside the scope of
ARI Standard 550/590-98 certification program
Fouling Factor
Performance tables are based on water with a fouling factor of
) / 0176 . 0 ( , , / 0001 . 0
2 2
kW C m or BTU F hr ft
° × ° × ×
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
3.
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. To ensure optimum unit
operation, maintain proper water treatment.