- Spx Cooling Fan User Manual

10
Operation
When changing fan direction of rotation, allow a minimum of two
minutes time delay before energizing the fan motor.
Hot Water Distribution System
Hot water from the process flows through an inlet to each cell, which sup-
plies a distribution header and a system of branch arms and nozzles. Each
distribution header may be equipped with a vent standpipe to minimize
water hammer, to maintain a slightly pressurized water distribution system,
and to provide vacuum release at pump shutdown.
If an Amertap condenser tube cleaning system is part of plant equip-
ment, care should be taken during operation to back-wash the strainer
section only after the sponge rubber cleaning balls are removed from
the system by trapping them in the collector. Balls that are allowed to
enter the cooling tower supply piping may clog some of the nozzles,
although the generous flow paths through the nozzles make this un-
likely. However, balls escaping the nozzles will accumulate on top of
the fill, ultimately causing unequal water distribution that will affect
thermal performance. The top of the fill should be frequently checked
until such time as the operational sequence of the Amertap system
assures that no balls enter the cooling tower distribution system.
Fill
Water leaving the nozzles is scattered uniformly over the fill plan area.
The water flows through the fill, coating each fill sheet to maximize water
surface exposure to the air being moved by the fans.
Drift Eliminators
Air leaving the fill passes through a level of drift eliminators covering the
entire plan area of the tower. The purpose of these drift eliminators is
to minimize the amount of water that is caused to exit the tower by the
velocity of the moving airstream.
Cold Water Collection Basin
Water leaving the fill falls into the cold water basin that forms the base of
the tower. The normal water level in the concrete basin is approximately
12” (305 mm) below the top of the curb. Adjust the make-up water supply
to maintain approximately this water level. Maintain sufficient water depth
to prevent cavitation.
▲ Caution