SPX Cooling Technologies MARLEY CLASS F400 - Manual (Page 5)

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Entering water temperature in excess of 125°F may result in fill
deformation.
TOWER PERFORMANCE –Keep the cooling tower clean and water distribu-
tion uniform to obtain continued maximum cooling capacity.
The capacity of a cooling tower to cool water to a given cold water temperature
varies with the wet-bulb temperature and the heat load applied to the cooling
tower. As the wet-bulb temperature drops, the cold water temperature also
drops. However, the cold water temperature does not drop linearly with the
wet-bulb temperature.
A cooling tower will not control heat load. The flow rate of water circulated
through the cooling tower will determine the temperature range of cooling in
conjunction with a given heat load. The hot water and cold water temperatures
will increase with higher heat loads.
HOT WATER DISTRIBUTION SYSTEM –Maintain uniform water distribution
at the nozzles (uniform spray cone). The amount of water circulated should
approximate the contract requirements and the nozzle pressure should be kept
constant. Lower pressures may indicate excessive losses in the piping system
and/or insufficient pump capacity; greater pressures might indicate clogged
nozzles and/or overpumping. If a greatly reduced water flow rate is desired, it
may be advisable to change nozzle sizes to obtain the desired pressure and
maintain proper water distribution. An SPX Cooling Technologies engineer
can advise minimum and maximum flow rates for even distribution.
COLD WATER COLLECTION BASIN –A suitable depth must be maintained
to keep the pumps from pulling air into the line. The amount of “make-up”
water required to keep the water in the collection basin at the required depth
depends upon the “evaporation loss” and “blowdown” .
FAN DRIVE –When using two-speed motors, allow a time delay of 20 seconds
minimum after de-energizing the high-speed winding and before energizing
the low-speed winding. Tremendous stresses are placed on driven machinery
and motors unless the motors are allowed to slow to low-speed RPM or less
before the low-speed winding is energized.
Caution
➠
operation