13
Fluid Cooler Start-Up
Among other sources, outbreaks of Legionnaires’ Disease have report-
edly been traced to cooling towers and fluid coolers. Maintenance and
water treatment procedures that prevent amplification and dissemina-
tion of Legionella and other airborne bacteria should be formulated
and implemented BEFORE systems are operated and continued
regularly thereafter to avoid the risk of sickness or death.
Water System:
1. New installations should be cleaned and treated with biocides by a
water treatment expert before startup.
2. Remove any and all accumulated debris from fluid cooler. Pay par-
ticular attention to inside areas of collection water basin, distribution
water basins, louvers and drift eliminators. Make sure that cold water
suction screens are clear and properly installed.
3. Fill the water system to an approximate depth of 8″ (203 mm) in the
depressed area of the collection water basin. This is the recommended
operating water level. Adjust the float valve so that it is 75% open at
that level. Continue filling the system until the water reaches a level
approximately 3 mm below the lip of the overflow.
4. Start your pump(s) and check for proper rotation as indicated by
the arrow on the pump cover, observe system operation. A certain
amount of “pump-down” of the basin water level will occur before
water completes the circuit and begins to fall from the fill in the up-
per module. The amount of initial pump-down may be insufficient to
cause the float valve to open. However, you can check its operation
by pressing down on the operating lever to which the stem of the float
valve is attached.
Some trial and error adjustment of the float valve may be required to
balance the makeup water with tower operation. Ideally, the float valve
setting will be such that no water is wasted through the overflow at
pump shutdown. However, the water level after pump start-up must
be deep enough to assure positive pump suction.
5. Open the valve on the tower bleed line and adjust bleed to the recom-
mended rate. See Water Treatment section on page 20.
6. Continue pump operation for about 15 minutes, after which it is rec-
ommended that the water system be drained, flushed and refilled.
Operation
Warning
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