SPX Cooling Technologies 98-1514E user manual Tower Operation, General

Operation

When biocidal treatment has been maintained at a satisfactory level for at least six hours, the fan may be turned on and the system returned to service. Resume the standard water treatment program, including biocidal treatment.

Tower Operation

General:

The cold water temperature obtained from an operating cooling tower will vary with the following influences:

1.Heat load: With the fan in full operation, if the heat load increases, the cold water temperature will rise. If the heat load reduces, the cold water temperature will reduce.

Note that the number of degrees (“range”) through which the tower cools the water is established by the system heat load and the amount of water being circulated, in accordance with the following formula:

Range – °F	=	Heat Load (Btu/hr)
		GPM x 500
	or — in SI units
Range – °C	=	Heat Load (kilowatts)
		Liters/sec x 4.187

The cooling tower establishes only the cold water temperature attain- able under any operating circumstance.

2.Air wet-bulb temperature: Cold water temperature will also vary with the wet-bulb temperature of the air entering the louvered faces of the tower. Reduced wet-bulb temperatures will result in colder water temperatures. However, the cold water temperature will not vary to the same extent as the wet-bulb. For example, a 20°F (11 °C) reduction in wet-bulb may result in only a 15°F (8°C) reduction in cold water temperature.

3.Water flow rate: Increasing the water flow rate (GPM or L/s) will cause a slight elevation in cold water temperature, while reducing the water flow rate will cause the cold water temperature to decrease slightly. However, at a given heat load (see formula above), water flow reduc- tions also cause an increase in the incoming hot water temperature. Use care to prevent the hot water from exceeding 125°F, (52°C) in

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