BAC Trillium Series - Cleansing Circulation; Pump and Float Control

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Unit Operation
Modes of Operation
Dry Mode
Pre-Cooler Mode
Cleansing Circulation
TrilliumSeries™ Adiabatic Products utilizes a patented process in Pre-Cooler Mode to
manage the water: maximizing Pre-Cooler Pad wetting while minimizing water consumption
and maintaining hygiene. This process is called Cleansing Circulation.
In this process, water enters the unit and is circulated throughout, never remaining still.
To keep the water clean, the drain valve opens every few hours (field adjustable, based
on water quality) for a couple of minutes to drain the water in the sump. The make-up
valve then opens to allow fresh water to enter the unit. If the Water Monitoring package is
ordered, this periodic draining schedule will be replaced with a schedule based on water
conductivity (see page 23).
Figure 23. Cleansing Circulation
Periodic Drain Cycle
The few minute drain cycle described above as part of the Cleansing Circulation process is
called the Periodic Drain Cycle which occurs every two hours.
Daily Drain Cycle
Once a day, the unit will drain the sump and flush it with fresh water for two minutes
(adjustable). The pump will turn off and the basin will remain empty.
Pump and Float Control
• When the unit is in Pre-Cooler Mode, the pump will be in operation. The pump works
in concert with the float switch, make-up valve, and dump valve to ensure reliable
operation and that a proper water level is maintained for the long life of the pump.
• When the outside air temperature reaches setpoint, the make-up water valve (NC) and
the drain valve (NO) will be energized, and water will begin to fill the basin.
• When the basin is full, the float switch makes and sends a signal to the The EcoFlex™
Controls. After a brief delay, the pump will energize.
• After another brief delay, the make-up valve is de-energized.
• As water evaporates, the water level in the sump will drop due to evaporation. When it
drops below the minimum level, the float switch will trigger the EcoFlex™ Controls to
open the make-up valve until the water level reaches normal.
• If the make-up valve is open for a certain time and the float switch is not made, the
pump will be de-energized to protect the pump from running dry.