bac volume ii · 2008-11-21 · single cell capacity: 128 – 428 nominal tons 384 – 1,284 gpm at...

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Series 1500Open Cooling Towers

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Product DetailProduct Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D37

Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D39

Construction Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D41

Custom Features & Options . . . . . . . . . . . . . . . . . . . . . . . . . . . .D43

Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D45

Engineering Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D47

Structural Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D49

Engineering Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D51

Engineering Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . .D92

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Baltimore Aircoil Company

Single Cell Capacity:128 – 428 Nominal Tons384 – 1,284 GPM at 95ºF/85ºF/78ºF

Series 1500 Cooling Towers minimize the operating, installation, and maintenance costs associated with

both new and replacement cooling tower projects. The Series 1500 delivers independently verified, fully

rated thermal performance over a wide range of flow and temperature requirements. Standard design

features minimize the costs associated with enclosures, support requirements, electrical service, piping,

and rigging.

Series 1500 Cooling Towers• Ideal replacement unit

• Single side air inlet

• Low energy consumption

• Low installed cost

• Easy maintenance

• Reliable year-round operation

• Long service life

• ASHRAE Standard 90.1 compliant

• 5-year warranty on mechanical equipment

Series 1500 Open Cooling Towers

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...because temperature matters™

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Ideal Replacement Unit• Support Steel – Units are designed to mount

directly on existing support steel of many cooling towers (both crossflow and counterflow).

• Electrical Service – Fan motor configurations can be supplied to match existing wiring.

• Enclosures – Units fit in most existing enclosures with little or no modifications due to the single air inlet design.

Low Energy Consumption• Evaporative cooling equipment minimizes the energy consumption of the entire system because it

provides lower operating temperatures. The owner saves money while conserving natural resources and reducing environmental impact.

• Series 1500 Cooling Towers provide the heat rejection required at the lowest possible energy input via:

• High efficiency, low horsepower axial fans • High efficiency BACross® Fill surface, which provides maximum air/water contact time at

low air pressure drops• Independent fan motors (optional, see page D43 for details)

• Variable frequency drives (optional, see page G1 for details)• ENERGY-MISER® Fan System (optional, see page D44 for details)• BALTIGUARD PLUSTM Fan System (optional, see page G1 for details)

• All units meet or exceed ASHRAE Standard 90.1 energy efficiency requirements.

Benefits

Counterflow cooling tower replacement

Single air inlet provides installation flexibility in tight layouts

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Low Installed Cost• Single Side Air Inlet – Units can be placed close

to solid walls, reducing the size of enclosures and allowing for more profitable use of premium space.

• Modular Design – The modular design minimizes the size and weight of the heaviest lift, allowing for the use of smaller, less costly cranes.

Easy Maintenance• Easy Cleaning – The fill surface is elevated above the

sloped cold water basin floor to facilitate flushing of dirt and debris from this critical area.

• Hinged Access Doors and Standard Internal Walkway –Provide easy entry to the spacious plenum for routine drive maintenance.

• Accessibility – Make-up, drain, overflow and optional basin accessories are accessible from outside the unit.

• Inlet Strainer – Dirt and debris are collected by an integral strainer before reaching the hot water basins, keeping nozzles clean.

Reliable Year-Round Operation• BALTIDRIVE® Power Train – Backed by a 5-year fan motor

and drive warranty, the BALTIDRIVE® Power Train utilizes special corrosion-resistant materials of construction and state-of-the-art technology to ensure ease of maintenance and reliable year-round performance.

• Separate Air Inlet Louvers – Reduce the potential for excessive scale build-up and damaging ice formations at the air/water interface by providing a line of sight from the outside the unit into the fill.

Long Service Life• Materials of Construction – Various materials are available to meet the corrosion resistance, unit

operating life, and budgetary requirements of any project (see page D43 for construction options).

The unit shown ships in two pieces to minimize shipping and rigging costs

Series 1500 with optional external service platform

Standard inlet strainer

Access to strainer, make-up andbasin accessories from outside

the tower

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Construction Details

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Heavy-Duty Construction• G-235 (Z700 metric) hot-dip galvanized

steel panels

BALTIDRIVE® Power Train• Premium quality, solid-backed, multi-groove belt

• Corrosion resistant cast aluminum sheaves

• Heavy-duty bearings (280,000 hour average life)

• Cooling tower duty fan motor

• 5-year motor and drive warranty

Low HP Axial Fan• High efficiency

• Quiet operation

• Corrosion resistant

Water Distribution System• Large orifice non-clog nozzles

• Steel covers in easy to remove sections

• Low pump head gravity distribution basin

• Integral strainer

BACross® Fill with Integral Drift Eliminators (Not Shown)

• High efficiency heat transfer surface

• Polyvinyl chloride (PVC)

• Impervious to rot, decay and biological attack

• Flame spread rating of 5 per ASTM E84-77a

FRP Air Inlet Louvers• Corrosion resistant

• UV protected finish

• Maintenance free

Cold Water Basin• Sloped cold water basin for easy cleaning

• Suction strainer with anti-vortex hood

• Adjustable water make-up assembly

• Integral internal walkway as standard

Hinged Access Doors• Inward swinging door on each end wall

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Construction Options• Standard Construction:

Steel panels and structural elements are constructed of heavy-gauge G-235 (Z700) hot-dip galvanized steel.

• Optional BALTIBOND® Corrosion Protection System:The BALTIBOND® Corrosion Protection System, a hybrid polymer coating used to extend equipment life, is applied to all hot-dip galvanized steel components of the cooling tower.

• Optional Stainless Steel Cold Water Basin:A Series 300 stainless steel cold water basin is available. Seams between panels inside the cold water basin are welded. The basin is leak tested at the factory and welded seams are provided with a 5-year leak-proof warranty.

• Optional Stainless Steel Hot and Cold Water Basins:Series 300 stainless steel hot water basins are provided in addition to the cold water basin described above.

• Optional Stainless Steel Construction:Steel panels and structural elements are constructed of Series 300 stainless steel. Seams between panels inside the cold water basin are welded. The basin is leak tested at the factory and welded seams are provided with a 5-year leak-proof warranty.

See page M26 for more details on the materials described above.

Factory Mutual ApprovalMulti-cell Series 1500 Cooling Towers are available with Factory Mutual (FM) approved construction as an option.

Fan Drive SystemThe fan drive system provides the cooling air necessary to reject unwanted heat from the systemto the atmosphere. The standard fan drive system onthe Series 1500 is the exclusive BALTIDRIVE® PowerTrain. This BAC engineered drive system consists ofa specially designed powerband and two cast aluminum sheaves located on minimum shaft centerline distances to maximize belt life. A coolingtower duty fan motor, custom engineered for BAC toprovide maximum performance for cooling towerservice, is provided and backed by BAC’s comprehensive 5-year motor and fan drive warranty.

Independent Fan OperationModels 15296 through 15425 are provided with one fan motor driving two fans as standard. Theindependent fan option consists of one fan motor and drive assembly for each fan to allow independentoperation, adding an additional step of fan cycling and capacity control.

Custom Features and Options

BALTIDRIVE® Power Train System

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ENERGY-MISER® Fan SystemThe ENERGY-MISER® Fan System consists of twostandard single-speed fan motor and drive assemblies. One drive assembly is sized for fullspeed and load, and the other is sized approximately2/3 speed and consumes only 1/3 the design horsepower. This configuration allows the system tobe operated like a two-speed motor, but with thereserve capacity of a standby motor in the event offailure. As a minimum, approximately 70% capacitywill be available from the low horsepower motor, evenon a design wet-bulb day. Controls and wiring are thesame as those required for a two-speed, two-windingmotor. Significant energy savings are achieved whenoperating at low speed during periods of reduced load and/or low wet-bulb temperatures.

BALTIGUARD PLUSTM Fan SystemThe BALTIGUARD PLUSTM Fan System builds on the advantages of the ENERGY-MISER® Fan Systemby adding a VFD to the smaller motor. Using tthe VFD on the smaller fan motor, as opposed to the larger motor, reduces the cost of the VFD, and wiring for the motor. For more information on the BALTIGUARD PLUSTM Fan System refer to page G1.

Low Sound AlternativesThe low sound levels generated by Series 1500 Cooling Towers make them suitable for installation inmost environments. For situations when one direction is particularly sound sensitive, the unit can be oriented so that the side opposite the air inlet faces the sound-sensitive direction. The Series 1500 isalso available with a low sound fan or a “Whisper Quiet” fan that significantly reduces the sound levelsgenerated from the tower with minimal impact on thermal performance. The cooling tower thermal performance with the low sound fan has been certified in accordance with CTI Standard STD-201. Forextremely sound sensitive installations, factory designed, tested and rated sound attenuation is availablefor both the air intake and discharge.

Whisper Quiet FanSeries 1500 models are available with a "Whisper Quiet" fan thatsignificantly reduces the sound levels generated from the unit withminimal impact on thermal performance.

Equipment Controls BAC control panels are specifically designed to work seamlesslywith all BAC units and engineered to meet you particular application.For more on BAC Equipment Controls, see pages G1-G13.

ENERGY-MISER® Fan System

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Service PlatformsFor access to the motor and drive assemblies on Models15296 through 15425, an internal ladder with or withoutupper service platform with handrails is available. For external service, louver face platforms and access door platforms are options that can be added to the cooling towereither when the unit is purchased or as an aftermarket item.Safety gates are available for all handrail openings suppliedby BAC. All components are designed to meet OSHArequirements.

Vibration Cutout SwitchA factory mounted vibration cutout switch is available to effectively protect against rotating equipmentfailure. BAC can provide either a mechanical or solid-state electronic vibration cutout switch in aNEMA 4 enclosure to ensure reliable protection. Additional contacts can be provided on either switchtype to activate an alarm. Remote reset capability is also available on either switch type.

Basin HeatersCooling towers exposed to below freezing ambient temperatures require protection to prevent freezingof the water in the cold water basin when the unit is idle. Factory-installed electric immersion heaters,which maintain +40°F (4.4°C) water temperature, are a simple and inexpensive way of providing suchprotection.

Heater Sizing Data

Accessories

External platform at louver face

Internal ladder and service platformStandard internal walkway

Model Number 0ºF (-17.8ºC) Ambient Heaters (kW) -20ºF (-28.9ºC) Ambient Heaters (kW)

15146 to 15282 8 12

15296 to 15425 12 16

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Electric Water Level Control PackageThe electric water level control replaces the standardmechanical make-up valve when a more precisewater level control is required. This package consistsof a conductance-actuated level control mounted inthe basin and a solenoid activated valve in the make-up water line. The valve is slow closing to minimize water hammer.

Extended Lubrication LinesExtended lubrication lines are available for lubricationof the fan shaft bearings. Fittings are located insidethe plenum area next to the access door.

High Temperature FillIf operation above 120°F (48.9°C) is anticipated, anoptional high temperature fill material is available which increases the maximum allowableentering water temperature to 135°F (57.2°C).

Air Inlet ScreensWire mesh screens are available factory-installedover the air inlet louvers to prevent debris from entering the tower.

Basin Sweeper PipingBasin sweeper piping is an effective method of eliminating sediment that may collect in the coldwater basin of the tower. A complete piping system,including nozzles, is provided for connection in thetower basin to side stream filtration equipment (by others). For more information on filtrationsystems, see page M159.

Side Outlet Depressed Sump BoxA side outlet depressed sump box is available forfield installation below the base of the tower to facilitate jobsite piping. The outlet connection isdesigned to mate with an ASME Class 150 flat faceflange. See the Connection Guide (page M56) for more information on standard and optional unitconnection types.

Electric water level control package

Grease fittings at the access door (inset) & bearings with the extended lubrication line option

Basin sweeper piping

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Do not use for construction. Refer to factory certified dimensions. This handbook includes data currentat the time of publication, which should be reconfirmed at the time of purchase. Up-to-date engineeringdata, free product selection software, and more can be found at www.BaltimoreAircoil.com.

Notes: 1. Operating weight is based on the water level in the cold water

basin at overflow height. If a lower operating weight is neededto meet design requirements, your local BAC Representative can provide additional assistance.

2. The specific size of the inlet and outlet connection may vary with the design cooling water flow rate. Consult unit print fordimensions.

3. Unless otherwise indicated, all connections 3" and smaller areMPT. Connections 4" and larger are beveled for welding and mechanically grooved.

4. The heaviest section for all models except 15214 through15282 is the upper section. Models 15146 to 15219 ship in one piece.

5. Models 15296 through 15425 – 2 1/8”

6. Models 15296 through 15425 – 8”

7. Models 15146 through 15219 and 15296 through 15425 – 2 3/4”

8. Models 15296 through 15425 – 1 1/2”

9. Nominal tons of cooling represents 3 GPM of water cooled from 95ºF to 85ºF at a 78ºF entering wet-bulb temperature.

Engineering Data

Single Cell Unit

8" WATER OUTLET2

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6 MAKE UP

WATER INLETAIR OUT

AIR IN

AIR IN

ACCESS DOOR

OVERFLOW

DRAIN

MODELNUMBER

NOMINALTONNAGE9

MOTOR HPIND. FANMOTOROPTION

FAN(CFM)

WEIGHTS (lbs) DIMENSIONSINLETCONN.2OPERATING1 SHIPPING

HEAVIESTSECTION L H A C

15146 146 7.5 N/A 40,320 7,920 3,940 3,940

8’ 6” 10’ 3” N/A 9’ 9” 6”15160 160 10 N/A 44,190 7,940 3,960 3,96015176 176 15 N/A 48,160 7,990 4,010 4,010

15162 162 7.5 N/A 43,080 8,610 4,200 4,200

8’ 6” 11’ 7” N/A 11’ 1” 6”15177 177 10 N/A 47,070 8,630 4,220 4,22015201 201 15 N/A 53,540 8,690 4,280 4,28015219 219 20 N/A 58,240 8,710 4,300 4,300

15200 200 10 N/A 52,320 11,430 5,350 2,770

8’ 6” 14’ 3” 7’ 5” 13’ 9” 6”15227 227 15 N/A 59,380 11,490 5,410 2,78015250 250 20 N/A 65,400 11,510 5,430 2,800

15214 214 10 N/A 56,610 12,450 5,640 2,920

8’ 6” 15’ 7” 8’ 9” 15’ 1” 6”15245 245 15 N/A 64,810 12,510 5,700 2,92015270 270 20 N/A 71,420 12,530 5,720 2,92015282 282 25 N/A 74,600 12,610 5,800 2,920

15296 296 15 (2) 7.5 77,440 15,540 6,750 3,540

12’ 1” 14’ 3” 7’ 5” 13’ 9” 8”15325 325 20 (2) 10 85,030 15,590 6,800 3,59015350 350 25 (2) 15 91,560 15,640 6,850 3,64015368 368 30 (2) 15 96,280 15,660 6,870 3,660

15310 310 15 (2) 7.5 82,000 17,050 7,070 3,540

12’ 1” 15’ 7” 8’ 9” 15’ 1” 8”15340 340 20 (2) 10 89,940 17,100 7,120 3,59015365 365 25 (2) 15 96,550 17,150 7,170 3,64015385 387 30 (2) 15 101,840 17,180 7,200 3,67015425 428 40 (2) 20 112,340 17,450 7,470 3,940

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Notes: 1. Operating weight is for tower with water level in the cold water

basin at overflow. If a lower operating weight is needed to meet design requirements, your local BAC Representative canprovide additional assistance.

2. The specific size of the inlet and outlet connection may vary with the cooling water design flow rate. Consult unit print for dimensions.

3. Unless otherwise indicated, all connections 3" and smaller are MPT. Connections 4" and larger are beveled for welding and mechanically grooved.

4. The heaviest section for all models except 15214 through 15282 is the upper section. Models 15146 to 15219 ship in one piece.

5. Models 15296 through 15425 – 2 1/8”

6. Models 15296 through 15425 – 8”

7. Models 15146 through 15219 and 15296 through 15425 – 2 3/4”

8. Models 15296 through 15425 – 1 1/2”

9. Nominal tons of cooling represents 3 GPM of water cooled from 95ºF to an 85ºF at a 78ºF entering wet-bulb temperature.

Multi-Cell Units

8" WATER OUTLET

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MAKE UP

AIR IN

AIR IN

AIR OUT

ACCESS DOORS(BOTH ENDS)

OVERFLOW

DRAIN

CONNECTIONS SAME BOTH ENDS

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See page D92 for EngineeringConsiderations.

MODELNUMBER

NOMINALTONNAGE9

MOTOR HPIND. FANMOTOROPTION

FAN(CFM)

WEIGHTS (lbs) DIMENSIONSINLETCONN.2

OPERATING1 SHIPPINGHEAVIESTSECTION L H A C D

15146-2 292 (2) 7.5 N/A 80,640 15,840 7,880 3,940

17’ 2” 10’ 3” N/A 9’ 9” 4’ 3” (2) 6”15160-2 320 (2) 10 N/A 88,380 15,880 7,920 3,96015176-2 352 (2) 15 N/A 96,320 15,890 8,020 4,010

15162-2 324 (2) 7.5 N/A 86,160 17,220 8,400 4,200

17’ 2” 11’ 7” N/A 11’ 1” 4’ 3” (2) 6”15177-2 354 (2) 10 N/A 94,140 17,260 8,440 4,22015201-2 402 (2) 15 N/A 106,900 17,380 8,560 4,28015219-2 438 (2) 20 N/A 116,480 17,420 8,600 4,300

15200-2 400 (2) 10 N/A 104,640 22,860 10,700 2,770

17’ 2” 14’ 3” 7’ 5” 13’ 9” 4’ 3” (2) 6”15227-2 454 (2) 15 N/A 118,760 22,980 10,820 2,78015250-2 500 (2) 20 N/A 130,800 23,020 10,860 2,800

15214-2 428 (2) 10 N/A 113,220 24,900 11,280 2,920

17’ 2” 15’ 7” 8’ 9” 15’ 1” 4’ 3” (2) 6”15245-2 490 (2) 15 N/A 129,620 25,020 11,400 2,92015270-2 540 (2) 20 N/A 142,840 25,060 11,440 2,92015282-2 564 (2) 25 N/A 149,200 25,220 11,600 2,920

15296-2 592 (2) 15 (4) 7.5 154,880 31,080 13,500 3,540

24’ 5” 14’ 3” 7’ 5” 13’ 9” 6’ 5/8” (2) 8”15325-2 650 (2) 20 (4) 10 170,060 31,180 13,600 3,59015350-2 700 (2) 25 (4) 15 183,120 31,280 13,700 3,64015368-2 736 (2) 30 (4) 15 192,560 31,320 13,740 3,660

15310-2 620 (2) 15 (4) 7.5 164,000 34,100 14,140 3,540

24’ 5” 15’ 7” 8’ 9” 15’ 1” 6’ 5/8” (2) 8”15340-2 680 (2) 20 (4) 10 179,880 34,200 14,240 3,59015365-2 730 (2) 25 (4) 15 193,100 34,300 14,340 3,64015385-2 774 (2) 30 (4) 15 203,680 34,360 14,400 3,67015425-2 856 (2) 40 (4) 20 224,860 34,900 14,940 3,940

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The recommended support arrangement for the Series 1500 Cooling Tower consists of parallel I-beamspositioned as shown in the following drawings. Besides providing adequate support, the steel also serves toraise the unit above any solid foundation to ensure access to the bottom of the tower. The Series 1500 mayalso be supported on columns at the anchor bolt locations shown in Plan A/C or Plan B. A minimum 12”x12”(304.8mm x 304.8mm) bearing surface must be provided under each of the concentrated load points (SeeNote 5). To support a Series 1500 Cooling Tower on columns or in an alternate steel support arrangement,consult your local BAC Representative.

Structural Support

Notes: 1. Support beams and anchor bolts are to be selected and installed

by others.

2. All supporting steel must be level at the top.

3. Beams must be selected in accordance with accepted structural practice. Maximum deflection of beam under unit to be 1/360 of span, not to exceed 1/2 inch.

4. All units can be furnished with an optional vibration isolation package, if required, to be installed between the tower and supporting steel. The BAC vibration isolation package is designed for units on support Plan A/C. When determining the length of steel beams, allow for the length of vibration isolation rails, as theymay be longer than the tower length shown above.

5. If point vibration isolation is used with multi-cell towers, the isolators must be located under the supporting steel, not between the support steel and the cooling towers.

6. If existing vibration isolator rails are being reused on a replacement project, springs/elastomers must be resized to match the new cooling tower weight distribution. Consult your local BAC Representative for details.

7. When using Alternative Plan A support arrangements with optional bottom water outlet, size and location restrictions will apply to water outlet piping. Consider the Cantilevered Plan A support arrangement or consult your local BAC Representative for details.

Plan A/C: Single-Cell and Multi-Cell Units

Plan A/C Plan B

Plan B: Single-Cell Units Only

MODEL NUMBER A L1 L15146 to 15282 6’ 9-3/4” 8’ 5-3/4” -

15296 to 15425 10’ 5-1/4” 12’ 1-1/4” -

15146-2 to 15282-2 6’ 9-3/4” 8’ 5-3/4” 17’ 2”

15296-2 to 15425-2 10’ 5-1/4” 12’ 1-1/4” 24’ 5”

MODEL NUMBER A L15146 to 15282 8’ 3-1/2” 8’ 5-3/4”

15296 to 15425 11’ 11” 12’ 1-1/4”

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See Notes on previous page.

For replacement installations, the Series 1500 Cooling Tower has been designed to match the supportingsteel of most existing counterflow and crossflow cooling towers without modifications. Shown below are themost common steel support arrangements which can be accommodated by the Series 1500. If individualpoint support is required, or if steel arrangement is not as shown below, consult your local BACRepresentative for assistance.

Structural Support Alternatives

Alternative Plan A: Typical Dimensions for Single-Cell and Multi-Cell Units

Cantilevered Plan A: Typical Dimensions for Single-Cell and Multi-Cell Units

Alternative Plan ACantilevered Plan A

MODEL NUMBER UNIT REPLACED A B C L115146 to 15282 VLT/VST 8’ 9-1/8” 1’ 6-7/16” 8’ 3-1/2” 8’ 5-3/4”

15296 to 15425VLT/VST/VXT 8’ 11-1/4” 1’ 5-3/8” 11’ 11” 12’ 1-1/4”VXT/VXMT 9’ 7-1/2” 1’ 1-1/4” 11’ 11” 12’ 1-1/4”

15146 to 15282CFT 8’ 0” 1’ 11” 8’ 3-1/2” 8’ 5-3/4”

SERIES 3000 8’ 3-1/4” 1’ 9-3/8” 8’ 3-1/2” 8’ 5-3/4”

15296 to 15425CFT 8’ 0” 1’ 11” 11’ 11” 12’ 1-1/4”

SERIES 3000 9’ 6” 1’ 2” 11’ 11” 12’ 1-1/4”

MODEL NUMBER UNIT REPLACED A B C1 C2 L1

15146 to 15282 VLT/VST 8’ 9-1/8” 2’ 11-3/4” 8’ 3-1/2” 6’ 9-3/4” 8’ 5-3/4”

15296 to 15425VLT/VST/VXT 8’ 11-1/4” 2’ 9-5/8” 11’ 11” 10’ 5-1/4” 12’ 1-1/4”

VXT/VXMT 9’ 7-1/2” 2’ 1-3/8” 11’ 11” 10’ 5-1/4” 12’ 1-1/4”

15146 to 15282CFT 8’ 0” 3’ 8-7/8” 8’ 3-1/2” 6’ 9-3/4” 8’ 5-3/4”

SERIES 3000 8’ 3-1/4” 3’ 5-5/8” 8’ 3-1/2” 6’ 9-3/4” 8’ 5-3/4”

15296 to 15425CFT 8’ 0” 3’ 8-7/8” 11’ 11” 10’ 5-1/4” 12’ 1-1/4”

SERIES 3000 9’ 6” 2’ 2-7/8” 11’ 11” 10’ 5-1/4” 12’ 1-1/4”

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1.0 Cooling Tower

1.1 General: Furnish and install _____ factory-assem-bled, induced draft, crossflow cooling tower(s) with verti-cal air discharge conforming in all aspects to the specifi-cations, schedules and as shown on the plans. Overalldimensions shall not exceed approximately _____ft (mm)long x _____ ft (mm) wide x _____ ft (mm) high. The totalconnected fan horsepower shall not exceed _____ HP(kW). The cooling tower(s) shall be Baltimore AircoilCompany Model ____________________.

1.2 Thermal Capacity: The cooling tower(s) shall be war-ranted by the manufacturer to cool _____ USGPM (l/s) ofwater from ___ °F(°C) to ___ °F(°C) at ___ °F(°C) entering wet bulb temperature. Additionally, the thermalperformance shall be certified by the Cooling TechnologyInstitute in accordance with CTI Certification StandardSTD-201. Lacking such certification, a field acceptancetest shall be conducted within the warranty period inaccordance with CTI Acceptance Test Code ATC-105, bythe Cooling Technology Institute or other qualified independent third party testing agency. Manufacturer’sperformance guarantees or performance bonds withoutCTI Certification or independent field thermal performance test shall not be accepted. The coolingtower shall comply with the energy efficiency requirements of ASHRAE Standard 90.1.

1.3 Corrosion Resistant Construction: Unless otherwisenoted in this specification, all steel panels and structuralmembers shall be constructed of heavy-gauge G-235(Z700 metric) galvanized steel with all edges given a protective coating of zinc-rich compound.

(Alternate) 1.3 Corrosion Resistant Construction: Unlessotherwise noted in this specification, all steel panels andstructural members must be protected with the BALTI-BOND® Corrosion Protection System. The system shallconsist of G-235 (Z700 metric) hot-dip galvanized steelprepared in a four-step (clean, pretreat, rinse, dry)process with an electrostatically sprayed, thermosettinghybrid polymer fuse-bonded to the substrate during athermally activated curing stage and monitored by a 23-step quality assurance program. Coatings other thanthe BALTIBOND® Corrosion Protection System must besubmitted to the engineer for pre-approval. Approvedequals must have undergone testing, resulting in the following results as a minimum:

1. When X-scribed to the steel substrate it shall be able to withstand 6000 hours of 5% salt spray per ASTM B117 without blistering, chipping, or loss of adhesion;

2. When X-scribed to the steel substrate it shall be able to withstand 6000 hours of exposure to acidic (pH=4.0) and alkaline (pH=11.0) water solutions at 95ºF (35ºC) without signs of chemical attack;

3. Shall withstand impact of 160 in-lbs per ASTM D2794without fracture or delamination of the polymer layer;

4. Shall withstand 6000 hours of ultraviolet radiation equivalent to 120,000 hours of noontime sun exposure without loss of functional properties;

5. Shall withstand 200 thermal shock cycles between -25ºF and +180ºF (-32ºC and 82ºC) and without loss of adhesion or other deterioration;

6. Shall withstand 6000 hours of exposure to 60 psi(42184.2 kg/m2) water jet without signs of wear or erosion.

(Alternate) 1.3 Series 300 Stainless Steel Construction:All steel panels and structural members, including thecasing panels, hot and cold water basins, distribution covers, fan deck and fan cylinder shall be constructed ofSeries 300 stainless steel and assembled with Series 300stainless steel nut and bolt fasteners. All factory seams inthe cold water basin shall be welded to ensure watertightassembly and shall be unconditionally warranted againstleaks for five (5) years from date of shipment.

1.4 Quality Assurance: The cooling tower manufacturershall have a Management System certified by an accredited registrar as complying with the requirements ofISO-9001:2000 to ensure consistent quality of productsand services.

1.5 Wind and Seismic Forces: When supported as recommended, the unit shall be suitable for applicationsrequiring equipment anchorage to resist wind loads up to30 psf (146.6 kg/m2) acting on the full vertical projectedarea with 16 psf (78.1kg/m2) acting simultaneously on thefull horizontal projected area or seismic forces of 161% ofthe operating weight acting in the horizontal direction, and24% of the operating weight acting in the vertical directionapplied at the center of gravity. Loads are appropriate forSeismic Zone 4 assuming an Importance factor of 1.0,and soil profile SD, and rigid mounting to the supportingstructure per the 1997 Uniform Building Code.

2.0 Construction Details

2.1 Cold Water Basin: The cold water basin shall be constructed of heavy-gauge steel panels and structuralmembers. Basin shall include a depressed section withdrain/clean-out connection. The basin area under the fillshall be sloped toward the depressed section to facilitatecleaning. Standard basin accessories shall include abrass make-up valve with a large diameter plastic float foreasy adjustment of operating water level.

(Alternate) 2.1 Cold Water Basin: The cold water basinshall be constructed of heavy-gauge Series 300 stainlesssteel panels and structural members. All factory seamsshall be welded to ensure watertight construction and

Engineering SpecificationsSee our website at www.BaltimoreAircoil.com for an electronic copy of product engineering specifications.

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welded seams shall be warranted against leaks for a period of five (5) years from date of shipment. Stainlesssteel basins with bolted seams are not acceptable. Basinshall include a depressed section with drain/clean-outconnection. The basin area under the fill shall be slopedtoward the depressed center section to facilitate cleaning.Standard basin accessories shall include a brass make-upvalve with large diameter plastic float for easy adjustmentof the operating water level.

2.2 Water Outlet: The water outlet connection shall bebeveled for welding and grooved for mechanical couplingor bolt hole circle designed to accept an ASME Class 150flat face flange. The outlet shall be provided with large-area lift out strainers with perforated openings sized smaller than the water nozzles and an anti-vortexingdevice to prevent air entrainment. The strainer and vortexdevice shall be constructed of the same materials as thecold water basin to prevent dissimilar metal corrosion.

2.3 Water Distribution System: The distribution systemshall be furnished with a single water inlet. The pipe stubconnection shall be beveled for welding and grooved formechanical coupling. The hot water distribution systemshall consist of an integral strainer that feeds to an opengravity type basin, for easy cleaning, and constructed ofheavy-gauge G-235 (Z700 metric) hot-dip galvanizedsteel. The basins must be accessible from outside theunit and serviceable during tower operation. Basin weirsand plastic metering orifices shall be provided to assureeven distribution of the water over the fill. Lift-off distribution covers shall be constructed of heavy-gauge G-235 (Z700) hot-dip galvanized steel. Gravity flow nozzles shall be snap-in type for easy removal. Shouldpressurized nozzles be used, they shall utilize grommets,which ensure easy removal.

(Alternate) 2.3 Water Distribution System: The distributionsystem shall be furnished with a single water inlet. Thepipe stub connection shall be beveled for welding andgrooved for mechanical coupling. The hot water distribution system shall consist of an integral strainer thatfeeds to an open gravity type basin, for easy cleaning,and constructed of heavy-gauge, Series 300 stainlesssteel. The basins must be accessible from outside of theunit and serviceable during tower operation. Basin weirsand plastic metering orifices shall be provided to assureeven distribution of the water over the fill. Lift-off distribution covers shall be constructed of heavy-gauge,Series 300 stainless steel. Gravity flow nozzles shall besnap-in type for easy removal. Should pressurized nozzles be used, they shall utilize grommets, whichensure easy removal.

3.0 Mechanical Equipment

3.1 Fan(s): Fan(s) shall be axial flow with aluminum alloyblades selected to provide optimum cooling tower thermal

performance with minimal sound levels. Air shall discharge through a fan cylinder designed for streamlinedair entry and minimum tip clearance for maximum fan efficiency. The top of the fan cylinder shall be equippedwith a conical, non-sagging removable fan guard.

3.2 Bearings: Fan(s) and shaft(s) shall be supported byheavy-duty, self-aligning, grease packed ball bearings withmoisture proof seals and integral slinger collars, designedfor a minimum L10 life of 40,000 hours (280,000 Hr. Avg.Life).

3.3 Fan Drive: The fan(s) shall be driven by a one-piece,multi-groove, solid back V-type powerband with taper locksheaves designed for 150% of the motor nameplatehorsepower. The powerband shall be constructed of neo-prene reinforced polyester cord and be specificallydesigned for cooling tower service.

3.4 Sheaves: Fan and motor sheave(s) shall be fabricatedfrom corrosion-resistant materials to minimize mainte-nance and ensure maximum drive and powerband operating life.

3.5 Fan Motor: Fan motor(s) shall be totally enclosed airover (TEAO), reversible, squirrel cage, ball bearing typedesigned specifically for cooling tower service. The motorshall be furnished with special moisture protection onwinding, shafts, and bearings and appropriately labeledfor “cooling tower duty.”

(Alternate) 3.5 Fan Motor: Fan motor(s) shall be totallyenclosed air over (TEAO), reversible, squirrel cage, ballbearing type designed specifically for cooling tower service. The motor shall be furnished with special moisture protection on winding, shafts, and bearings andappropriately labeled for “cooling tower duty.” Fan motorsshall be inverter duty type designed per NEMA StandardMG1, Section IV Part 31.

3.6 Mechanical Equipment Warranty: The fan(s), fanshaft(s), bearings, mechanical equipment support, and fanmotor shall be warranted against defects in materials andworkmanship for a period of five (5) years from date ofshipment.

3.7 ENERGY-MISER® Fan System (optional): Two single-speed fan motors, one sized for full speed andload, the other sized for 2/3 speed and approximately 1/3the full load horsepower, shall be provided for capacitycontrol and stand-by protection from drive or motor failure.Two-speed motor(s) are not an acceptable alternative.

(Alternate) 3.4 BALTIGUARD PLUS™ Fan System: Twosingle speed fan motors, one sized for load, the othersized for 1/3 of the full load horsepower shall be providedin each cell for capacity control and standby protection

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from drive or motor failure. The manufacturer of the equip-ment shall supply controls for the larger motor, a VFD forthe smaller motor and factory programmed logic controllerto maximize energy saving for off peak load and wet-bulbconditions.

4.0 Fill and Drift Eliminators

4.1 Fill and Drift Eliminators: The fill and integral drift elimi-nators shall be formed from self-extinguishing (per ASTM-568) polyvinyl chloride (PVC) having a flame spread ratingof 5 per ASTM E84 and shall be impervious to rot, decay,fungus and biological attack. The fill shall be suitable forentering water temperatures up to and including 120°F(48.8°C). The fill shall be manufactured, tested and ratedby the cooling tower manufacturer and shall be elevatedabove the cold water basin to facilitate cleaning.

(Alternate) 4.1 Fill and Drift Eliminators: The high tempera-ture fill and integral drift eliminators shall be formed fromself-extinguishing (per ASTM-568) polyvinyl chloride (PVC)having a flame spread rating of 5 per ASTM E84 and shallbe impervious to rot, decay, fungus and biological attack.The high temperature fill shall be suitable for enteringwater temperatures up to and including 135°F (57.2°C).The fill shall be manufactured, tested and rated by thecooling tower manufacturer and shall be elevated abovethe cold water basin to facilitate cleaning.

5.0 Air Inlet Louvers

5.1 Air Inlet Louvers: Air inlet louvers shall be separatefrom the fill and be removable to provide easy access forinspection of the air/water interface at the louver surface.Louvers shall prevent water splash-out during fan cyclingand be constructed of maintenance free, corrosion resist-ant, UV protected, fiberglass reinforced polyester (FRP).

(Alternate) 5.1 FM Approval (Multi-cell): The cooling towersshall be constructed with galvanized steel casing panelsand louvers that shall meet the requirements of FM.(Alternate) 5.1 FM Approval (Multi-cell): The cooling towersshall be constructed with Series 300 stainless steel casingpanels and louvers that shall meet the requirements of FM.

6.0 Access

6.1 Plenum Access: Hinged access doors shall be provid-ed on two sides of the tower for access into plenum sec-tion.

7.0 Sound

7.1 Sound Level: To maintain the quality of the local envi-ronment, the maximum sound pressure levels (dB) meas-ured 50 ft (15240 mm) from the cooling tower operating atfull fan speed shall not exceed the sound levels detailedbelow. If the tower exceeds these conditions the towermust be either oversized and reduced in horsepower, pro-vided with a low sound fan, or provided with sound attenu-ation.

(Alternate) 7.1 Sound Level: To maintain the quality of thelocal environment, the cooling tower shall be furnishedwith a low sound fan. The thermal performance of the cooling tower when furnished with the low sound fan shallbe certified by the Cooling Technology Institute in accordance with paragraph 1.2 of this specification.Maximum sound pressure levels (dB) measured 50 ft(15240 mm) from the cooling tower operating at full fanspeed shall not exceed the sound levels detailed below.

8.0 Accessories:

8.1 Vibration Isolation Rails: Spring-type vibration isolationrails, constructed of steel channels and base plates, painted with a rust-resistant primer shall be provided tominimize vibration transmission from the tower to the building structure. The isolators shall be designed for astatic deflection of 1” (25.4 mm) and a maximum windspeed of 50 mph (80 km/h).

(Alternate) 8.1 Vibration Isolation Rails: Spring-type vibra-tion isolation rails, constructed of steel channels and baseplates, coated with a 0.003” (.076 mm) layer of zinc afterfabrication shall be provided to minimize vibration trans-mission from the tower to the building structure. The isola-tors shall be designed for a static deflection of 1” (25.4mm) and a maximum wind speed of 50 mph (80 km/h).

8.2 Basin Heater(s): The cooling tower cold water basinshall be provided with electric heater(s) to prevent freezingin low ambient conditions. The heater(s) shall be selectedto maintain 40°F (4.4°C) basin water temperatures at_____°F (°C) ambient. The heater(s) shall be______V/____phase/___Hz electric and shall be providedwith low water cutout and thermostat.

(Alternate) 8.2 Basin Heaters: A steam coil shall be factoryinstalled in the depressed section of the cold water basinto prevent freezing during cold water shutdown. Thesteam coil shall be capable of maintaining 40°F (4.4°C)basin water temperature at a –20°F (-28.8°C) ambienttemperature given 5 psig (34 Kpa) at the coil inlet connection.

(Alternate) 8.2 Basin Heaters: A steam injector shall befactory installed in the cold water basin section to preventfreezing during cold water shutdown. Steam injector shallbe capable of maintaining 40°F (4.4°C) basin water temperature at a ___°F (°C) ambient temperature given 10 psig (68 Kpa) at the inlet connection.

Location 63 125 250 500 1000 2000 4000 8000 dB(A)

Discharge

Air Inlet

Side wall

Back wall

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8.3 Basin Water Level Control: The cooling tower manufac-turer shall provide an electric water level control (EWLC)system. The system shall consist of water level sensing andcontrol units in quantities and locations as indicated on thedrawings. Each water level sensing and control unit shallconsist of the following: NEMA 4 enclosure with gasketedaccess cover; solid state controls including all necessaryrelays and contacts to achieve the specified sequence ofoperation; stainless steel water level sensing electrodes withbrass holder; Schedule 40 PVC standpipe assembly withvent holes, and all necessary stainless steel mounting hardware. Provide PVC union directly below the controlenclosure to facilitate the removal and access of electrodesand control enclosure.

The number and position of water level sensing electrodesshall be provided to sense the following: high water level ,low water level, high water alarm level, low water alarm, andheater safety cutout.

8.4 Vibration Cutout Switch: Provide mechanical local resetvibration switch. The mechanical vibration cut out switch willbe guaranteed to trip at a point so as not to cause damageto the cooling tower. To ensure this, the trip point will be afrequency range of 0 to 3,600 RPM and a trip point of 0.2 to2.0 g’s.

(Alternate) 8.4 Vibration Cutout Switch: Provide electronicremote reset vibration switch with contact for BAS monitor-ing. Wiring shall be by the installing contractor. The elec-tronic vibration cut out switch shall be set to trip at a point soas not to cause damage to the cooling tower. The trip pointwill be 0.45 in/sec (0.0114 m/sec).

8.5 Basin Sweeper Piping: The cold water basin of the cool-ing tower shall be equipped with PVC basin sweeper pipingwith plastic eductor nozzles. The piping should create a gridunder the fill section and force all dirt and debris to thedepressed section of the cold water basin.

8.6 Air Intake Option: Provide removable hot dip galvanizedsteel 1”x1” (25.4 mm x 25.4 mm) mesh air intake screens.

(Alternate) 8.6 Air Intake Option: Provide removable hot dipgalvanized steel 1”x1” (25.4 mm x 25.4 mm) mesh air intakescreens protected with the BALTIBOND® CorrosionProtection system or Series 300 stainless steel.

(Alternate) 8.6 Air intake Option: Provide removable Series300 stainless steel 1”x1” (25.4 mm x 25.4 mm) mesh airintake screens.

8.7 Access Door Platform: A galvanized steel platform andaluminum ladder to grade shall be provided at an accessdoor to access the plenum section of the cooling tower. Allworking surfaces shall be able to withstand 50 psf (244kg/m2) live load or 200 pound (90.7 kg) concentrated load.

8.7 Internal Platform: An internal platform shall be providedin the plenum section to provide for inspection and mainte-nance. All working surfaces shall be able to withstand 50psf (244 kg/m2) live load or 200 pound (90.7 kg) concentrat-

ed load. Other components of the cooling tower, i.e. basinfloor and fill/drift eliminators, shall not be considered aninternal working surface. Cooling tower manufacturers thatrequire that these surfaces be used as a working platformshall provide a 5-year extended warranty to the Owner torepair any damage to these surfaces caused by routinemaintenance.

8.8 Fan Cylinder Extension: To extend the height of thetower equal to the surrounding enclosure, the cooling towershall be provided with ____ft (mm) of fan cylinder extension.The fan cylinder extension shall match the construction ofthe fan deck.

9.0 Equipment Controls (Optional)

9.1 Variable Frequency Drive(s): A variable frequency drive(VFD) shall be provided for each fan motor. The supplier ofthe VFD shall be the manufacturer of the evaporative coolingequipment. The VFD shall have a 3-contactor bypass, 3%input line reactor, a removable keypad, an RS232 terminalfor PC connection, and a circuit breaker disconnect. Fuseprotection will not be accepted. Control voltage shall be 24Vto minimize the size of the enclosure which should notexceed _____ ft x _____ ft x ____ ft and the weight shouldnot exceed ____ lbs. VFD shall be provided in a NEMA(1)(3R)(12) enclosure. The VFD shall be compatible with a(ModBus) (LonWorks) (Johnson N2) Building AutomationSystem.

OR

9.1 Enclosed Controls: An enclosed control panel shall beprovided for each cell of the evaporative cooling equipment.The panel shall include full voltage, non-reversing (FVNR)fan motor and pump motor (if applicable) starters in a common enclosure. The panel shall be provided with a maina circuit breaker disconnect and a separate circuit breakerfor each motor or speed. Fuse protection will not be accepted. Panels containing basin heaters shall have anEarth Leakage Breaker containing ground fault protection.Starters above 25 A shall be NEMA rated. IEC starters willbe accepted for motors below 25 A. Panel shall include a120V/60Hz control power transformer, Hand-Off-Auto switches for each starter or contactor, and pilot lights foreach component. Enclosed controls shall be provided in aNEMA (1)(3R)(4)(4X)(12) enclosure.

Optional enclosed control features: (A temperature sensorshall be provided with the enclosed controls.)(A temperaturecontroller shall be provided with the enclosed controls.)(A basin heater contactor with circuit breaker shall be provided.)(A vibration cutout switch input shall be provided.)

9.2 Safety Switch(es): A heavy-duty, non-fusible safety disconnect switch shall be provided by the manufacturer ofthe evaporative cooling equipment. Switch shall be single-throw, 3-pole design, rated up to 600 VAC. Switch shall havetriple padlocking capability, a visible double break rotaryblade mechanism, a clearly visible On/Off handle, an interlocking mechanism to prevent door opening with handlein On position, and a clear line shield. Safety switch shall beprovided in a NEMA (1)(3R)(12) enclosure.

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LocationUnits must have an adequate supply of fresh air to the air inlet(s). When units are located adjacent to

building walls or in enclosures, care must be taken to ensure that the warm, saturated discharge air is not

deflected off surrounding walls or enclosures and drawn back into the air inlet(s).

CAUTION:

Each unit should be located and positioned to prevent the introduction of the warm discharge air

and the associated drift, which may contain chemical or biological contaminants including

Legionella, into the ventilation systems of the building on which the unit is located or those of

adjacent buildings.

For detailed recommendations on layout, refer to our web site, www.BaltimoreAircoil.com, or consult

your local BAC Representative.

For Series V products, bottom screens or solid bottom panels may be desirable or necessary for safety,

depending on the location and conditions at the installation site.

Piping and ValvesPiping must be sized and installed in accordance with good piping practice. All piping should be supported

by pipe hangers or other supports, not by the unit. On open systems, in order to prevent basin overflow at

shutdown and to ensure satisfactory pump operation at start-up, all heat exchangers and as much piping as

possible should be installed below the operating level of the cooling tower.

Some units may require flow balancing valves (supplied by others) at the hot water inlets to balance the flow

to individual inlets and cells. External shutoff valves (supplied by others) may also be required if the system

design necessitates the isolation of individual cells.

When multiple cells are used on a common system, equalizing lines should be installed between the cold

water basins to ensure balanced water level in all cells. It is good engineering practice to valve the inlet and

outlet of each tower separately for servicing. The shut-off valves can be used, if necessary, to adjust any

minor unbalanced condition in water flow to or from the units.

Engineering Considerations -Cooling Towers

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Capacity ControlVariable Frequency Drives (VFD)

Variable speed drives offer the most precise control of leaving fluid temperature or condensing pressure at

the lowest energy cost. VFDs provide compliance with the speed control requirements for heat rejection

equipment in current energy codes, such as ASHRAE Standard 90.1 and California Title 24. In addition,

soft-starts, stops, and smooth accelerations prolong the life of the mechanical system, including belts,

bearings, and gears. Sound is also reduced, by minimizing start-up noise and running the tower at the lowest

fan speed necessary to meet system demand. Note that units with VFDs require the use of inverter duty

motors, designed per NEMA Standard MG 1, Section IV, Part 31. This standard recognizes the increased

stresses placed on motors by these drive systems. Note that the use of a non-inverter duty motor in these

applications may void the motor warranty.

WARNING:

When the fan speed is to be changed from the factory-set speed, including through the use of a

variable speed control device, steps must be taken to avoid operating at or near fan speeds that cause

a resonance with the unit or its supporting structure. At start-up, the variable frequency drive should

be cycled slowly between zero and full speed and any speeds that cause a noticeable resonance in the

unit should be “locked out” by the variable speed drive.

Fan Cycling

Fan cycling is the simplest method of capacity control. The number of steps of capacity control can be

increased using the ENERGY-MISER® Fan System, BALTIGUARD PLUS™ Fan System, the independent

motor option, or two-speed fan motors in conjunction with fan cycling (see “Custom Features & Options”

section of the appropriate product line to determine whether the ENERGY-MISER® Fan System, BALTIGUARD

PLUS™ Fan System, or the independent fan motor option are available for the particular product line;

two-speed motors are available for all product lines with either belt or gear fan drive systems. All of these

options provide substantial energy savings when compared to simple fan cycling, especially the BALTIGUARD

PLUS™ System, which provides energy savings and redundancy at a low cost.

WARNING:

Rapid on-off cycling can cause the fan motor to overheat. It is recommended that controls be set to

allow a maximum of 6 on-off cycles per hour.

Capacity Control Dampers (Series V Models Only)

On Series V models, modulating capacity control dampers are available to provide better leaving water

temperature control than can be obtained from fan cycling alone. See page D80 or contact your local BAC

Representative for more details.

Vibration Cutout SwitchesVibration cutout switches are recommended on all installations. Vibration cutout switches are designed to

interrupt power to the fan motor and can provide an alarm to the operator in the event of excessive vibration.

BAC offers both electronic and mechanical vibration cutout switches on all cooling tower models.

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Water TreatmentAs water evaporates in an open cooling tower, the dissolved solids originally present in the water remain in

the system. The concentration of these dissolved solids increases rapidly and can cause scale and corrosion.

In addition, airborne impurities and biological contaminants, including Legionella, may be introduced into the

circulating water. To control all potential contaminants, a water treatment program must be employed. In

many cases, a simple bleed-off may be adequate for control of scale and corrosion. Note: Bleed lines are to

be provided and installed by others. However, biological contamination, including Legionella, can be

controlled only through the use of biocides. Such treatment should be initiated at system startup, after periods

of equipment shutdown, and continued regularly thereafter. For more information, consult the appropriate

Operating and Maintenance Manual.

When a water treatment program is employed, it must be compatible with construction materials. The pH of

the circulating water must be maintained between 6.5 and 9.0. Units having galvanized steel construction and

a circulating water pH of 8.3 or higher will require periodic passivation of the galvanized steel to prevent the

accumulation of white, waxy, nonprotective zinc corrosion called white rust. Batch feeding of chemicals into

the unit is not recommended. If units are constructed with optional corrosion resistant materials, acid

treatment may be considered; however, the water quality must be maintained within the guidelines set forth in

the Operating and Maintenance Manual.

For complete Water Quality Guidelines, see the appropriate Operating and Maintenance Instruction

Manual, available at www.BaltimoreAircoil.com

For specific recommendations on water treatment, contact a competent water treatment supplier.

Fill CompatibilityBAC’s standard fill is constructed of polyvinyl chloride (PVC) and has a flame spread rating of 5 per ASTM

Standard E84. The PVC fill surface is compatible with the water found in most evaporative cooling

applications. The maximum allowable water temperature for each product is as shown in the following table:

Maximum Allowable Water Temperature by Fill Material

For applications where the entering water temperature exceeds the limits shown above, contact your localBAC Representative for assistance.

Product Line Standard PVC High Temperature PVC

Series 3000 130ºF (54.4ºC) 140ºF (60.0ºC)

Series 1500 120ºF (48.9ºC) 135ºF (57.2ºC)

FXT 125ºF (51.7ºC) 140ºF (60.0ºC)

Series V 130ºF (54.4ºC)140ºF (54.4ºC) for BALTIBOND® Corrsion Protection System Unit;

150ºF (65.6ºC for Galvanized & Stainless Steel Units

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Sound LevelsSound rating data is available for all BAC Cooling Towers. When calculating the sound levels generated by aunit, the designer must take into account the effects of the geometry of the tower as well as the distance anddirection from the unit to noise-sensitive areas. Low sound fans and intake and discharge sound attenuationcan be supplied on certain models to provide reduced sound characteristics (see the “Custom Features andOptions” section of the appropriate product line for details). The ENERGY-MISER® Fan System, two-speedmotors, or variable frequency drives can also be used to reduce sound during periods of non-peak thermalloads. For more information on sound and how it relates to evaporative cooling equipment, see page M124.For detailed low sound selections, please consult your local BAC Representative.

Protection Against Basin Water FreezingWhen a unit is shut down in freezing weather, the basin water must be protected by draining to an indoor

auxiliary remote sump tank (see page H5 for remote sump engineering data; page M28 for sizing guidelines)

or by providing supplementary heat to the cold water basin. Supplementary heat can be provided by electric

immersion heaters or in some cases, hot water or steam coils, or steam injectors. All exposed water piping,

make-up lines, and spray pumps (if applicable) that do not drain at shutdown should be traced with electric

heater tape and insulated.

Indoor Installations (Applicable to Series V Models Only)Many indoor installations require the use of inlet and/or discharge ductwork. Units installed with inlet ductwork must be ordered with solid bottom panels. Generally, intake ducts are used only on smaller

units while the equipment room is used as a plenum for larger units. Discharge ductwork will normally be

required to carry the saturated discharge air from the building.

Both intake and discharge ductwork must have access doors to allow servicing of the fan assembly, drift

eliminators, and water distribution system. All ductwork should be symmetrical and designed to provide even

air distribution across the face of air intakes and discharge openings.

WARNING:

The discharge opening must be positioned to prevent the introduction of discharge air into the freshair intakes serving the unit or the ventilation systems of adjacent buildings.

Note: Axial fan units are not suitable for indoor installations.

SafetyAdequate precautions, appropriate for the installation and location of these products, should be taken to

safeguard the public from possible injury and the equipment and the premises from damage. Operation,

maintenance and repair of this equipment should be undertaken only by personnel qualified to do so. Proper

care, procedures and tools must be used in handling, lifting, installing, operating, maintaining, and repairing

this equipment to prevent personal injury and/or property damage.

WarrantiesPlease refer to the Limitation of Warranties applicable to and in effect at the time of the sale/purchase of

these products.

bac volume ii · 2008-11-21 · single cell capacity: 128 – 428 nominal tons 384 – 1,284 gpm at...

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