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promoted as necessary for effective microbial control. However, properly
applied sodium hypochlorite programs work well at a fraction of the cost.
In many situations, the more expensive products are overfed or otherwise
misused. Another commonly observed problem is the over dosing of
phosphate and phosphonate inhibitors. This is problematic because the
limiting nutrient for microorganisms in water systems is almost always
phosphate; overfeed of phosphate and/or phosphonate products aggravates
microbial foulding by fertilizing it (McCoy 2005).
Pilot-scale Cooling Tower (PCT)
Pilot cooling towers (PCTs) have been used to simulate all the processes
in open recirculating cooling tower systems. PCTs provide a means for
well-controlled scientifically defensible comparisons of microbial control
programs. Any situation encountered in the real world of HVAC cooling
for building water systems can be simulated and studies in these pilot-scale
cooling towers.
