COOLING TOWER:

Note: Sensor data is currently unavailable for this system. However, we are working on publishing this data to the web. For questions on the progress of this project, please contact the ITLL Staff.

  • General Description
  • Operation
  • Technical Specifications

    • General Description

    [Cooling Tower Simplified Diagram] The sole purpose of the cooling tower is to provide chilled water (or glycol solution) to the air handling unit (AHU-1).

    Cooling is accomplished by blowing outside air past the cooling coils and, (when is above 55°F), spraying water over the exterior of the cooling coil, assisting with cooling through evaporation of the spray water. The spray water falls into a shallow reservoir in the fluid cooler, where it is treated with anti-bacterial chemicals. These treatments are critical for preventing build-up on the exterior of the cooling coil which would effectively insulate it and decrease its heat-transfer performance.

    It is interesting to note that while many pieces of equipment experience performance losses (derating) at higher altitudes, evaporative cooler performance actually improves. Although the air density is lower, causing less efficient heat transfer directly to the air, this derate is more than offset by the lower water vapor pressure at altitude (that is, water evaporates more easily at higher altitudes).

    With approximately 91% of the heat exchange occurring by evaporating water from the outside of the coils and only 9% by convection, conduction and radiation, the gain in performance due to reduced water vapor pressure is more than that lost due to lower air mass flow at high altitudes.

    Operation

    Upon a call for cooling, if the outside air temperature is at least 55°F (adjustable), the fluid cooler sump fills, for which 15 minutes (adjustable) is allowed. If the outside air temperature drops below 40°F (adjustable) for at least 60 minutes, the sump is drained to prevent freezing.

    is maintained at 45°F (adjustable) by cycling the fluid cooler pump and fan (two-speed, low and high). If the outside air temperature is above 55°F, the condenser water pump runs continuously.
    If the outside air temperature drops below 55°F (adjustable), the fluid cooler pump and fan are shut down ( ).

    A shuts off the fluid cooler sump pump if the sump water level is low, while a vibration sensor shuts off the fluid cooler fan and sends an alarm signal to the Direct Digital Control (DDC) system if it senses excess vibration.



    Technical Specifications

    Fluid Cooler

    Plan Symbol

    FC-1

    Submittal Ref. #

    15710

    Location

    Outside

    Manufacturer

    Baltimore Air Coil

    Supplier

    LZP, Inc. (303) 744-1311

    Type

    Industrial Fluid Cooler

    Model No.

    BAC VFL94 PMXS

    Service

    Condenser water cooler

    Water Entering Temp.

    76°F

    Water Leaving Temp.

    68°F

    Water Pressure Drop

    38.5 ft (16.7 psi) head

    Coil Volume

    396 gal

    Ambient Air Temp.

    95°F drybulb

    Ambient Air Temp.

    63°F wetbulb

    Fan Motor Power

    15 Hp

    Fan Motor Voltage

    460 V, 3 ph.

    Fan Flow

    58,300 cfm @ 5400 ft elev.

    Spray Pump Motor Power

    2 Hp

    Spray Pump Motor Voltage

    460 V, 3 ph.

    Spray Pump Output

    340 gpm