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Bulletin 340IICTCooling Towers Advanced Features InInduced Draft, Counterflow TowersMember MCAAMechanical Contractors Association of AmericaMember C.T.I.Cooling Tower InstituteStainless Steel Basinsand Fiberglass CasingsAvailableOR EOT RIV TYM D ND AAN ARRWESIVUCL EEEX THR RAYE

EVAPCO ICTCooling TowersIt is well known in the industry that Induced Draft,Counter-Flow Cooling Towers provide the greatestoperating efficiency and easiest maintenanceaccessibility. Its vertical air discharge and low operatingweight provide more design flexibility making it thepreferred choice for most cooling tower applications.EVAPCO’s ICT Cooling Tower features the advantagesof the induced draft counter-flow cooling tower designand the high level of quality and service only EVAPCOprovides.The ICT is a heavy duty cooling tower well-suited forindustrial as well as commercial applications utilizing itsdurable construction and ease of maintenance. Its designsaves space, blends easily with architecturalsurroundings and offers low annual operating costs.The standard ICT is constructed with EVAPCO’s exclusiveEVAPCOAT Corrosion Protection System. In addition,EVAPCO offers the ICT with several optional materials ofconstruction including stainless steel and fiberglassreinforced polyester components.The EVAPCOAT Corrosion Protection System combinesheavy-gauge G-235 hot-dip galvanized steel constructionwith corrosion resistant PVC wet deck fill, PVC drifteliminators, PVC water distribution system, PVC inletlouvers and stainless steel suction strainers.For severe corrosive environments such as coastalregions and industrial plants, ICT models are availablewith the following optional materials: stainless steel basins,stainless steel basins with FRP casing, and completestainless steel construction. All designs successfullyincorporate the reliability and structural integrity ofstainless steel with the corrosion resistance of FRP.The thermal performance of the ICT tower, like allEVAPCO products, is backed by a full written guarantee.Through hundreds of hours of comprehensive testing,EVAPCO engineers established the performance of theICT to ensure rated performance without variation.Performance testing is conducted in EVAPCO’s new40,000 square foot environmental test facility.FeaturesCorrosion Protection SuperiorG-235 Hot-Dip Galvanized SteelEliminates Need for Costly, UnreliableEpoxy Paint FinishesMaintenance EasyReliable, Accessible ComponentsThree Year Warranty ExclusiveMotor and Fan AssemblyAir Discharge VerticalMinimizes Possibility of RecirculationDrift Eliminators EfficientSolve Water Carryover ProblemsReduce Water UsageLower Operating CostsLouver Design SuperiorEliminates Splashout, Reduces AlgaeGrade Motors IndustrialTotally Enclosed Motors StandardThis state-of-the-art research facility located at the Evapco WorldHeadquarters in Maryland is the largest and most advanced in theevaporative cooling industry.Inverter – Duty Motors Available forVFD Applications EVAPCO, INC. 19992

Optional Stainless Steel Basin withFiberglass Casing ConstructionAvailable on Models ICT 4-54 to 4-912steel fan support and interior steel components StainlessMaximum structural integrity and durabilityCasing and Fan Deck FRPIsophthalic polyester resin, gel coated, UV resistant, and specially treated toresist weatheringSteel Basin StainlessIncreased structural integrity and maximum corrosion protection FRP Fan Deck and CylinderFRP Casing Panels PVC Inlet LouversStainless Steel Cold WaterBasin 3

Design FeaturesVertical Air DischargeSuperior Louver DesignThe vertical air discharge of the ICT unit reduces thechance of air recirculation, since the warm humid air isdirected up and away from the unit. Layout considerationsand positioning are greatly simplified for all unit sizes.The air inlet louvers on the ICT are constructed ofcorrosion-free PVC. They are a two pass design thateliminates splashout and reduces the potential for algaeformation inside the tower.Air DischargeAir IntakeAir IntakeIn single pass louver systems, circulating water dropletstend to splashout, especially when the fans are shut off.With the two pass louver system, the water droplets arecaptured on the inward sloping pass, eliminatingsplashout problems.Another benefit of this design is that the louverscompletely enclose the basin area. Direct sunlight isblocked from the water inside the cooling tower, reducingthe potential of algae formation. Water treatment andmaintenance costs are substantially reduced.While effectively containing the recirculating water andblocking sunlight, the louver design has a low pressuredrop for efficient operation. Low fan energy consumptionresults with this superior louver system.VERTICAL DISCHARGEMost larger cooling towers have vertical air discharge,similar to the ICT, but many smaller capacity crossflowdesigns discharge the airhorizontally. Thisarrangement increasesthe chance of airrecirculation since the airis not directed up andaway from the tower. Theresults are reduced unitcapacity, systemoperational problems andincreased maintenanceexpense.Sun’sRaysAir IntakeLouverSystemLOUVER SYSTEMNO HORIZONTAL DISCHARGEThree Year Drive WarrantyReliable Year Round OperationThe ICT cooling tower is well suited for winter operation.With its counterflow design, the wet deck surface isencased, isolating the fill from freezing winds, and thusinhibiting ice formation on the fill.Crossflow designs have a well known tendency to formice along the inlet louvers and fill during cold weatheroperation. A buildup of ice at this point can quicklyreduce the unit capacity, require extensive downtime forremoval, and may require costly repairs to the fill andlouvers.The counterflow design of the ICT reduces the chances ofice formation and eliminates fill collapse.4EVAPCO provides a standard 3-year fan and motorwarranty on all ICT cooling towers. This unique warranty isdesigned to offerthe end useroptimumprotection againstfan and motorfailure. It is acomprehensiveplan whichincludes both thefan and the motor.This 3-yearwarranty isunsurpassed by any other cooling tower manufacturer.

Materials of ConstructionEVAPCOAT SystemHistorically, EVAPCO has been a leader in the designand implementation of corrosion protection techniques.EVAPCO’s Research and Development has producedmany design and material improvements to extend thelife of cooling towers. These include increasedgalvanizing thickness for steel, cold galvanizing forsheared edges and welds, PVC construction of fill anddrift eliminators, and stainless steel strainers.EVAPCO offers as standard the EVAPCOAT CorrosionProtection System on all cooling towers. This systemcombines heavy gauge G-235 hot-dip galvanized steelwith PVC and stainless steel materials in key areas tooffer maximum corrosion protection at an economicalprice.EVAPCOAT CONSTRUCTION WITH OPTIONAL 304 STAINLESS STEELBASIN (SHOWN)Optional Materials of ConstructionThe modular design of the ICT Cooling Tower alsoallows for specific areas to be enhanced for increasedcorrosion protection. EVAPCO offers two options forcost effective security from corrosion.Stainless Steel Basinwith Fiberglass Casing OptionCorrosive environments such as coastal installationsor industrial plants call for aggressive constructiontechniques. This option for cooling towers is designed toprovide further protection from corrosion and builds uponthe EVAPCOAT system with Type 304 stainless steel andFRP construction. Each component has been carefullyanalyzed and selected specifically for performance insevere duty applications.STAINLESS STEEL BASIN WITH FIBERGLASS CASING OPTIONStainless Steel Basinwith Fiberglass CasingThis construction feature is available for models ICT 4-54through ICT 4-912. The major design features are: Type 304 Stainless Steel BasinStainless steel is supplied for the entire basin area.The pan section of the cooling tower is a criticalcomponent since it provides the structural basefor the unit and is located in a severe corrosiveenvironment. Type 304 stainless steel basin for structural integrityand maximum corrosion protection. Fan support and interior steel components are Type304 stainless steel. Casing panels and fan deck are constructed of highgrade isophthalic polyester resin with color pigments.All FRP components are gel coated, UV resistant andspecifically treated to resist weathering. All Type 304 Stainless Steel ConstructionProvides the important advantages of both optimumstructural integrity and maximum corrosion protection.NOTE: Stainless Steel Basin with Fiberglass CasingOption is not available on models ICT 3-63 to 3-93.5

Quality ConstructionEfficient Drift EliminatorsWater Distribution SystemAn extremely efficient drift eliminator system is standardon the ICT. The system removes entrained water dropletsfrom the air stream to limit the drift rate to less than0.001% of the recirculating water rate.With a low drift rate, ICT cooling towers can be located inareas where minimum water carryover is critical, such asparking lots.The drift eliminators are constructed of an inert polyvinylchloride (PVC) plastic material which effectivelyeliminates corrosion of these vital components. They areassembled in sections to facilitate easy removal forinspection of the water distribution system.The water distribution system is made of Schedule 40PVC pipe and ABS plastic water diffusers for corrosionprotection in this key area. This system is greatlysimplified with only one header which is easily removablefor cleaning. The water diffusers have a minimumopening of 3/8 by 1 inch and are practically impossible toclog. They also have an anti-sludge ring extending intothe headers to prevent dirt from building up in the diffuseropening.DRIFT ELIMINATORWATER DISTRIBUTION SYSTEMCooling Tower FillThe patented* EVAPAK fill design used in the ICT isspecially designed to induce highly turbulent mixing ofthe air and water for superior heat transfer. Specialdrainage tips allow high water loadings without excessivepressure drop. The fill is constructed of inert polyvinylchloride (PVC). It will not rot or decay and is formulated towithstand water temperatures of 130 F. Because of theunique way in which the crossfluted sheets are bondedtogether, the structural integrity of the fill is greatlyenhanced, making the fill usable as a working platform.Stainless Steel StrainersFILLThe fill selected for the ICT has excellent fire resistantqualities. In tests conducted according to ASTM-E8481a, its flame spread rating was 5. (The flame spreadrating scale ranges from 0 for noncombustible to 100 forhighly combustible.)A high temperature fill is available for water temperaturesexceeding 130 F. Consult your EVAPCO representativefor further details.6*U.S. Patent No. 5,124,087One other component of the cooling tower which issubject toexcessive wearis the basinsuction strainer.The EVAPCOstandard for thisvery importantpart is Type 304stainless steel.STRAINER

Selection ProcedurePrinciple of OperationSelectionWarm water from the heat source is pumped to the waterdistribution system at the top of the tower. The water isdistributed over the wet deck fill by means of large orificenozzles. Simultaneously, air is drawn in through the airinlet louvers at the base of the tower and travels upwardthrough the wet deck fill opposite the water flow. A smallportion of the water is evaporated which removes theheat from the remaining water. The warm moist air isdrawn to the top of the cooling tower by the fan anddischarged to the atmosphere. The cool water drains tothe basin at the bottom of the tower and is returned tothe heat source.To size a cooling tower for any application it is necessaryto know the flow rate of water to be cooled in gpm, theentering water temperature, the desired leaving watertemperature, and the wet bulb temperature at the coolingtower location.ExampleGiven: to cool 200 gpm of water from 97 F to 85 F at 76 Fwet bulb temperature.Selection:1. Determine the range through which the water is to becooled:Entering Water Temperature – Leaving WaterTemperature Range(97 – 85 12 )2. Determine the approach of the leaving watertemperature to the wet bulb temperature:Leaving Water Temperature – Wet Bulb Temperature Approach(85 – 76 9 )3. Calculate the nominal ton load:Load flow rate (gpm) X range ( F) X 50015,000 btuh/ton200 X 12 X 500 80 nominal tons15,0004. Determine the application factor by turning to the 76 Fwet bulb table, page 10. Enter the top of the table inthe 12 range column and read down to the horizontalline which represents 9 approach. Read theapplication factor which lies at the intersection of thetwo columns.Application Factor .815. Determine Corrected Load:Nominal Load X Application Factor Corrected Load80X.81 64.8 corrected tonsPRINCIPLE OF OPERATION6. Select the proper cooling tower by referring to the ICTcapacity curves, page 12. Enter the chart at the designflow and read up to the corrected ton line. Select atower whose curve lies above the intersection point ofthe gpm and corrected ton lines. For the exampleshown above, select the model ICT 4-76.NOTE: Contact your local representative to receive acopy of EVAPCO’s exclusive EVAPSPEC IIComputer Selection Program.7

ApplicationFactors60 W.B.Approach 35.33.32.31.29.28.27.26.25.2562 W.B.Approach 4 W.B.Approach 41.39.38.37Shaded areas of tables indicate entering water temperature exceeding maximum 130 F.Consult factory for alternate high temperature fill options.8

66 W.B.Approach .27.26.25.24.23.22.2268 W.B.Approach 47.461.681.421.281.161