SPX Cooling Technologies Fluid Cooler Marley MC - Manual (Page 13)

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the fluid cooler fan, execute one of the two alternative biocidal treat-
ment programs described in the following:
• Resume treatment with the biocide which had been used prior
to shutdown. Utilize the services of the water treatment supplier.
Maintain the maximum recommended biocide residual (for the
specific biocide) for a sufficient period of time (residual and time
will vary with the biocide) to bring the system under good biological
control
or
• Treat the system with sodium hypochlorite to a level of 4 to 5 mg/L
(ppm) free chlorine residual at a pH of 7.0 to 7.6. The chlorine re-
sidual must be held at 4 to 5 mg/L (ppm) for six hours, measurable
with standard commercial water test kits.
If the fluid cooler has been in operation and then shut down for a
duration of time and not drained, perform one of the two previous
biocidal treatment programs directly to the fluid cooler storage vessel
(collection basin, drain down tank, etc.) without circulating stagnant
water over the fluid cooler or operating the fluid cooler fan.
After biocidal pretreatment has been successfully completed, cooling
water may be circulated over the tower with the fan off.
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.
Fluid Cooler Operation
general:
The cold process fluid temperature obtained from an operating fluid cooler
will vary with the following influences:
1. Heat load: With the fan in full operation, if the heat load increases,
the cold process fluid temperature will rise. If the heat load reduces,
the cold process fluid temperature will reduce.
Note that the number of degrees (“range”) through which the fluid
cooler cools the process fluid is established by the system heat load
and the amount of fluid being circulated, in accordance with the follow-
ing formula—formula is only valid for 100% water as process fluid:
Operation
➠
Range – °F =
Heat Load (Btu/hr)
GPM x 500
or — in SI units
Range – °C =
Heat Load (kilowatts)
Liters/sec x 4.187