period one
Types of Water Chillers
notes
Flow Rates and Temperatures
95°F | 44°F | 100°F | 41°F | ||||||||||
[35°C] | [6.7°C] | [37.8°C] | [5°C] | ||||||||||
85°F |
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| 85°F |
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[29.4°C] |
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| 54°F |
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| 57°F |
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| [12.2°C] |
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| [13.9°C] |
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| evaporator | 2.4 gpm/ton |
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| evaporator | 1.5 gpm/ton | ||||||
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| flow rate | [0.043 L/s/kW] |
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| flow rate | [0.027 L/s/kW] | ||||||
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| condenser | 3.0 gpm/ton |
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| condenser | 2.0 gpm/ton | ||||||
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| flow rate | [0.054 L/s/kW] |
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| flow rate | [0.036 L/s/kW] | ||||||
Figure 25
In the example system shown in Figure 25, the chilled water is cooled from 57°F [13.9°C] to 41°F [5°C] for a 16°F [8.9°C] ∆T. This reduces the water flow rate required from 2.4 gpm/ton [0.043 L/s/kW] to 1.5 gpm/ton [0.027 L/s/kW].
Reducing water flow rates either: 1) lowers system installed costs by reducing pipe, pump, valve, and cooling tower sizes, or 2) lowers system operating costs by using smaller pumps and smaller cooling tower fans. In some cases, both installed and operating costs can be saved.
The two ARI rating standards mentioned previously, as well as ASHRAE/IESNA Standard
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