BAC HXV Manual

OPERATION & MAINTENANCE MANUAL
HXV Hybrid Cooler

Inspect and clean as necessary: Start-Up Monthly Quarterly Annually Shutdown
Inspect general condition of the unit[2] and check unit for unusual
noise or vibration
Inspect cold water basin
Flush water distribution system/Inspect spray nozzles
Drain basin and piping
Inspect the CIS combined inlet shields, fill and eliminators
Inspect the CIS hail guards on top of the unit; safe access to be
provided by others
Check and adjust water level in the cold water basin
Check operation of make-up valve
Check and adjust bleed rate
Verify the operation and function of electric immersion heaters and
controls
Inspect if lifting lug access hole covers are installed after unit
installation; refer to the Rigging Manual for more details
Inspect unit finish
Mechanical equipment system: Start-Up Monthly Quarterly Annually Shutdown
Check belt condition
Adjust belt tension[3]
Lubricate fan shaft bearings
Lubricate motor base and adjusting screw
Check drive alignment
Check motor voltage and current
Check motor davit arm is locked in place and away from air stream[4}
Clean fan motor exterior
Check fan motor for proper rotation
Check general condition of the fan
Check fan for uniform pitch
Check fan for rotation without obstruction
Check and recoat steel shafts with RUST VETO®
Test vibration cutout switch
DANGER: Rotating equipment will cause
severe personal injury or death to persons who
come in contact. Do not perform any service,
maintenance, or inspection on or near the fans,
motors, and drives, or inside the unit without
first ensuring that the fans and pump motors
are disconnected, locked out, and tagged out.
NOTES:
1. Recommended service intervals are the minimum for typical installations.
Different environmental conditions may dictate more frequent servicing.
2. When operating in ambient temperatures below freezing, the unit should be
inspected more frequently. Refer to “Cold Weather Operation” on page 29 for
more details.
3. Tension on new belts must be readjusted after the first 24 hours of operation
and quarterly, thereafter.
4. Check at start-up and after each motor service.
Recommended Maintenance Intervals[1]

Table of Contents
OPERATION & MAINTENANCE » HXV HYBRID CLOSED CIRCUIT
COOLING TOWER
1
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Warnings and Cautions
2Safety Precautions
3Equipment Precautions
3General Maintenance Information
3Warranties
PART 1 Unit Operation & Storage
5Operation
6Sequence of Operation
7Start-Up Procedure
9Extended Shutdown
9Prolonged Outdoor Storage
PART 2 Detailed Component Maintenance Procedures
12 Cold Water Basin
13 Fan
14 Fan Drive System
16 Fan Motors
17 Fan Shaft Bearings
18 Heat Transfer Section
19 Water Distribution System
19 Water Level Control
PART 3 Corrosion Protection
22 Water Treatment
23 Corrosion and Scale Control
24 Chemical Treatment Requirements
24 Passivation
24 Biological Control
25 Long Term Care of Stainless Steel
26 System Cleaning
PART 4 Bleed Rate
27 Bleed Rate
PART 5 Cold Weather Operation
29 Inspection and Maintenance
29 Fan Section Icing Protection
30 Basin Water and Internal Piping Freeze Protection
31 Coil Freeze Protection
PART 6 Operation Considerations for Accessories
32 Basin Heater
32 Stand Alone BAC Heater Control Panel
33 CIS Hail Guards
34 Vibration Cutout Switch
35 Mechanical Vibration Cutout Switch
35 Electronic Vibration Cutout Switch
PART 7 Fan Control
36 Independent Fan Control
36 Variable Frequency Drive Operation
37 Resonant Speed
PART 8 Installation Instructions for Field Connections
39 Installation Instructions for Field Connections

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WARNING
• WARNING: The top horizontal surface of the unit is not intended to be used as a walking surface or working platform. If access to the top of the unit
is desired, the purchaser/end-user is cautioned to use appropriate means complying with applicable safety standards related to working on elevated
surfaces. If access to the top of the coil is required, place a piece of plywood at least 1/2 inch thick on top of the coil to protect the surface while
performing the recommended maintenance. When finished, carefully remove the plywood.
• WARNING: Hail guards are not designed to support the weight of a person or to be used as a storage or work surface for any equipment or tools. Use
of these hail guards as walking, working or storage surfaces may result in injury to personnel or damage to equipment. Units with hail guards should
not be covered with a plastic tarpaulin
• WARNING: When the fan speed of the unit is to be changed from the factory set speed, including changes achieved by the use of a variable fan speed
device, steps must be taken to avoid operation at or near the fan’s “critical speed” which could result in fan failure and possible personal injury or damage.
• WARNING: The recirculating water system may contain chemicals or biological contaminants, including Legionella, which could be harmful if
inhaled or ingested. Personnel exposed directly to the discharge airstream and the associated drift mists, generated during operation of the water
distribution system and/or fans, or mists produced by high pressure water jets or compressed air (if used to clean components of the recirculating
water system), must wear respiratory protection equipment approved for such use by governmental occupational safety and health authorities.
• WARNING: All electrical, mechanical, and rotating machinery are potential hazards, particularly for those not familiar with their design, construction,
and operation. Accordingly, use appropriate lockout procedures. Adequate safeguards (including the use of protective enclosures where necessary)
should be taken with this equipment both to safeguard the public from injury and to prevent damage to the equipment, its associated system, and
the premises.
• WARNING: A lockable disconnect switch should be located within sight of the unit for each fan motor associated with this equipment. Before
performing any type of service or inspection, make certain that all power has been disconnected, and the switch is locked out in the “OFF” position.
• WARNING: Dangerous voltages are present in this equipment. Disconnect the electrical service of the source and follow proper lock out and tag out
procedures to de-energize the circuit before servicing or replacing components.
• WARNING: To prevent possible contamination of the make-up water supply, install a backflow prevention method in accordance with applicable local
and national codes
• CAUTION: The operation, maintenance, and repair of this equipment shall be undertaken only by personnel authorized and qualified to do so. All such
personnel shall be thoroughly familiar with the equipment, the associated system and controls, and the procedures set forth in this manual. Proper
care, personal protective equipment, procedures, and tools must be used in handling, lifting, installing, operating, maintaining, and repairing this
equipment to prevent personal injury and/or property damage.
• DANGER: Rotating equipment will cause severe personal injury or death to persons who come in contact. Do not perform any service, maintenance or
inspection on or near the fans, motors, and drives, or inside the unit without first ensuring that the fans and pump motors are disconnected, locked out,
and tagged out.
• DANGER: On installations where there are multiple adjacent cells which may be traversed to gain access to another cell, all fan motors must be
disconnected, locked out and tagged out, including those on adjacent cells, before performing any service on or near the fans and drive systems, and
before traversing adjacent cells. Failure to follow this instruction may result in serious injury or death caused by contact with rotating equipment.
DANGER
CAUTION
Safety Precautions

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• The basin heater is not designed to prevent icing during unit operation.
• BAC units are typically installed immediately after shipment and many operate year round. However, if the unit is to be stored for a prolonged period of
time either before or after installation, certain precautions should be observed, as outlined in “Prolonged Outdoor Storage” on page 9.
• Ensure controls for the fan and pump motors are set to allow a maximum of six on-off cycles per hour to prevent motor overheating.
• Do not use steam or high pressure water to clean dry coils, PVC eliminators, combined inlet shields, fill, hail guards, or any other,
nonmetallic materials.
• Never use chloride or chlorine based solvents such as bleach or muriatic (hydrochloric) acid to clean stainless steel. It is important to rinse the surface
with warm water and wipe with a dry cloth after cleaning.
General Maintenance Information
Equipment Precautions
NOTICE
The services required to maintain a piece of evaporative cooling equipment are primarily a function of the quality of the air and water in the locality of the
installation:
• AIR: The unit should be located such that unusual quantities of industrial smoke, chemical fumes, salt, or heavy dust do not enter the equipment. Such
airborne impurities entering into the equipment and absorbed by the recirculating water can form a corrosive solution.
• WATER: As water evaporates from the equipment, dissolved solids are left behind, which were originally contained in the make-up water. These
dissolved solids may be either alkaline or acidic and as they are concentrated in the circulating water, they can cause scaling or accelerated corrosion.
The extent of impurities in the air and water determines the frequency of most maintenance services and also governs the extent of water treatment
which can vary from a simple continuous bleed and biological control to a sophisticated treatment system. Refer to “Water Treatment” on page 22 and
“Biological Control” on page 24 for more details.
Warranties
Please refer to the Limitation of Warranties in the submittal package applicable to and in effect at the time of the sale/purchase of these products.
Described in this manual are the recommended services for start-up, operation, and shutdown, and the approximate frequency of each.
• CAUTION: This equipment should never be operated without all fan screens, access panels, and access doors in place.
• CAUTION: Openings and/or submerged obstructions may exist in the bottom of the cold water basin. Use caution when walking inside the
equipment.
• CAUTION: Follow exposure control and personal protective equipment requirements as outlined in the MSDS for all recommended lubricant and
maintenance materials.
• CAUTION: BAC does not recommend field application of aftermarket coatings in the cold water basins of products equipped with electric immersion
heaters. The coating material may create an increased risk of fire if the heaters remain energized for any reason without sufficient water in the cold
water basin.

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Spray Water
Pump Assembly
Access Door
CIS Hail Guards
HXV HYBRID COOLER
Unit Operation and Storage
1
Prime Surface Coil (Wet
Coil): Fluid In
Coil Connection
Prime Surface Coil
(Wet Coil): Fluid Out
Coil Connection
Cold Water
Basin
External Ladder and
Safety Cage (Option)
External Platform
(Option)
Internal Access Ladder
and Platform
Air Inlet Louvers
Location of Water
Level Float Switches,
Basin Water Level
Control and Basin
Heater
Finned Coil (Dry
Coil) Connections
Figure 1. HXV Hybrid Cooler

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Operation
To optimize water and energy savings, the HXV Hybrid Cooler operates in two modes. In each
mode, capacity is controlled by fan motor modulation, and all of the process fluid flows
through the finned coil (dry coil) and then through the prime surface coil (wet coil).
Operating Modes (Con’t next page)
• Energy Saver Mode (Wet Mode): The spray water circulating pump distributes water
over the outside of the prime surface coil (wet coil). The spray water falls from the
prime surface coil over the fill surface, where the spray water temperature is further
reduced through evaporation. The cooled spray water collects in the cold water basin,
passes through the suction strainer and is pumped through the distribution system.
The fans draw air through the prime surface coil and through the fill surface (sensible
and latent heat transfer), which saturates the air before it enters the plenum and flows
into the fans. The saturated discharge air from the fans passes over the finned coil (dry
coil) to cool the process fluid (sensible heat transfer). This mode take full advantage of
evaporative cooling, and therefore reduces the fan energy necessary for cooling.
• Water Saver Mode (Dry Mode): The process fluid flows through the finned coil (dry coil)
and the prime surface coil. However, the spray water circulating pump is turned off,
which saves pump energy. There is only sensible heat transfer across both coils, as
the air passes over them. This mode is typically used during periods of lower ambient
temperatures or lower heat loads. During prolonged periods of dry mode operation,
draining the cold water basin is recommended, minimizing the need for freeze protection
and water treatment.
Unit Operation and
Storage
Operation
Figure 2a. Energy Saver Mode Figure 2b: Water Saver Mode
Internal Access Ladder
and Platform
NOTE: Schematic drawings are not
representations of actual units.
Refer to submittal for your specific
configuration.

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Operating Modes
• Adiabatic Mode (Balanced Water and
Energy Savings): The spray water
circulating pump distributes water
over the fill surface. The fans draw
air over the wetted fill where it is
adiabatically pre-cooled resulting is a
significantly lower air temperature and
greatly increasing the rate of sensible
heat transfer. The process fluid is
only circulated through the dry finned
coil. To enable this mode, a customer-
supplied three-way valve is needed.
Table 1. Sequence of Operation
Sequence of Operation with a 3-way Valve
Conditions Operation
No Heat Load Spray pump OFF; Fans OFF
Peak (design) operating conditions -
Ambient wet bulb ≥ Design wet bulb
Energy Saver Mode: Spray pump ON; Fan motors ON with VFD - fan
motors ramp up and down together. 3-way valve fully closed to allow
full flow through evaporative coil.
Fan speed is reduced based on load and reaches
customer-defined fan speed switchpoint OR
Ambient dry bulb ≤ Design adiabatic operation
switchpoint temp
Adiabatic Mode: Spray pump ON; Fan motors ON with VFD - fan
motors ramp up and down together. 3-way valve opens to bypass
evaporative coil, thereby saving water.
Fan speed is reduced based on load and reaches
customer-defined fan speed switchpoint OR
Water Saver Mode: Spray pump OFF; Fan motors ON with VFD - fan
motors ramp up and down together. 3-way valve fully closed to allow
full flow through evaporative coil to maximize dry performance.
NOTE: LWT= Fluid Cooler Leaving
Water Temperature
Sequence of Operation
The following is applicable to all sequences of operation:
• All fan speed control operation is based on leaving fluid temperatures.
• Basin heaters are interlocked with the spray pump, and only operate when the spray
pump is off and the basin temperature is less than 40°F.
• For extra coil freeze protection, spray pump can be locked out if ambient temperature
is less than 32°F
Figure 2c: Adiabatic Mode
Sequence of Operation without a 3-way Valve
Conditions Operation
No Heat Load Spray pump OFF; Fans OFF
Peak (design) operating conditions - Process
fluid leaving temperature ≥ Customer setpoint
Energy Saver Mode: Spray pump ON; Fan motors ON with VFD - fan
motors ramp up and down together. Process fluid flows through dry
coil and evaporative coil in series.
Fan speed is reduced based on load and reaches
customer-defined fan speed switchpoint OR
Ambient dry bulb ≤ Design dry operation switch-
point temp
Water Saver Mode: Spray pump OFF; Fan motors ON with VFD - fan
motors ramp up and down together. Process fluid flows through dry
coil and evaporative coil in series to maximize dry performance.
Table 1a: Sequence of Operation with a 3-way Valve
Table 1b: Sequence of Operation without a 3-way Valve

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Start-Up Procedure
General
• Verify the fan and unit pump motors are disconnected and locked out whenever
performing inspection or maintenance.
• If the unit is mounted on vibration isolators or isolation rails (by others), refer to the
vibration isolation manufacturer’s guidelines before loading/unloading weight from the unit.
Cleaning
• Inspect all spray nozzles and clean any which are dirty or clogged
(unlikely at initial start-up, but may be required for seasonal start-up).
• Clean all mechanical components, such as the fans and motors
(unlikely to be required at initial start-up).
• Flush the cold water basin interior to remove any accumulated dirt and debris.
• Remove, clean, and replace the strainer.
• Remove all dirt and debris from the fan guards.
• If necessary or required by local code, disinfect the HXV towers in accordance with
the most current versions of ASHRAE Standard 188: Legionellosis: Risk Management
for Building Water Systems, and ASHRAE Guideline 12: Minimizing the Risk of
Legionellosis Associated with Building Water Systems. This is not required on initial
startup unless water has been allowed to stagnate in the tower prior to startup.
Drain the cold water basin with the strainer in place.
Inspection
• Conduct external inspection of the equipment. Check for leaks, corrosion, and any
structural damage, including any damage to the hail guards.
• Conduct internal inspection of the equipment. Check for anything unusual such as
structural or mechanical component looseness or damage.
• Inspect piping and connections to verify they are secure.
• Inspect the visible coil surfaces. Any corrosion, damage, or obstructions should be
corrected.
• At seasonal start-up or after prolonged shutdown, check the motor insulation with
an insulation tester prior to the energizing the motor.
• Thoroughly inspect the fans for any mechanical or physical damage, and verify proper
fan tip clearance. Refer to Fan “Inspection & Maintenance” on page 13 for more details.
• Inspect the fill, eliminators, combined inlet shields and hail guards before start-up,
and clean them if necessary. Inspect the CIS hail guards annually or after a hail event.
See page 18 for more details.
Start-up
• Prior to seasonal start-up, check and adjust the belt tension.
• At initial start-up, the belt tension may not require adjustment as the drive will be
properly tensioned at the factory prior to shipment.
Unit Operation and
Storage
Sequence of Operation
Start-Up Procedure
General
Cleaning
Inspection
DANGER: Rotating equipment
will cause severe personal injury
or death to persons who come in
contact. Do not perform any service,
maintenance, or inspection on or
near the fans, motors, and drives,
or inside the unit without first
ensuring that the fans and pump
motors are disconnected, locked
out, and tagged out.
Considerations for initial start-up:
For units with independent fan control, see Page 36. For units with VFDs, see Page 36. For units with vibration
cutout switches, see Page 34.

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• Lubricate the fan shaft bearings. At initial
start-up, no bearing lubrication is required
unless the unit has been idle for more than
three months. Refer to page 17 for
more details.
• Apply a good quality, corrosion inhibiting
grease, such as one of those recommended
for lubricating the fan shaft bearings, to the
adjustable motor base and threaded rod.
See Figure 3.
• Apply RUST VETO®to steel shafts and bushings.
• Check the belt tension, and adjust if necessary. See page 14 for more details.
• Set the make-up valve float so the water shuts off at the operating level. See Table 2 on
page 12.
• Start the unit pump and check for the proper rotation indicated by the arrow on
the pump cover. Perform one of the following biocide treatment programs while
operating only the pump. Do not operate fans until after the biocide treatment has
been completed, and the biocide or chlorine levels have been reduced to normal
operational levels.
–If this is a startup after the tower has already operated with biocide treatment, then
resume treatment with the biocide that was used prior to shutdown. Operate only the
pump while maintaining the maximum recommended biocide residual for a sufficient
duration (residual and time will vary with the biocide) as recommended by the water
treatment supplier.
–Check the pH of the circulating water and, if necessary, adjust it to 7.0 - 7.6 pH.
Then, running the pump only, treat the system with sodium hypochlorite to maintain
a level of 4 to 5 mg/l (ppm) free chlorine (as Cl2) over a six hour period. Test kits for
measuring the free residual of chlorine are commercially available.
• After the biocide treatment period is completed, bring the biocide and/or chlorine levels
to normal operational levels.
• Resume operation with the standard water treatment program (including biocidal
treatment) as recommended by the water treatment supplier.
• Check that the float operated make-up valve is operating freely. Closely monitor water
level and adjust as necessary during the first 24 hours of operation. Refer to Table 2 for
more details.
• Inspect the heat transfer section as described on page 18 and inspect the water
distribution system as described on page 19.
• Passivation is required for galvanized coils. See page 24 for more details.
• On initial start-up, or if the fan motor has been rewired, briefly energize the fan motors
and note the direction of rotation. Fans should rotate in the direction indicated by the
arrow on the fan cowl.
• Run the fan in the manual position for several minutes and check for any unusual noises
or vibration. Correct as necessary.
• Test the vibration cutout switch (VCOS). See page 34 for more details.
• While the unit is operating at full speed under heat load and during near design ambient
conditions, check the current and voltage of all three phases (legs) of the fan motor. The
current should not exceed the nameplate full load amp (FLA) value.
• To identify resonances within the operating speed range, see page 37.
• For units with the optional Electric Water Level Control, see page 20.
Figure 3. Adjustable Motor Base
NOTICE: Ensure the controls for
the fan and pump motors are set
to allow a maximum of six on-off
cycles per hour to prevent motor
overheating.
After 24 hours of operation
under thermal load, perform the
following services:
9Check the unit for any unusual
noises or vibrations.
9Check the operating water
level in the cold water basins.
Adjust the make-up valve if
necessary. Thereafter, closely
monitor the cold water basin
operating level when the tower
is under thermal load near
design conditions, and adjust
as necessary to maintain an
operating level of 8 1/4”.
9Check the belt tension and
readjust if necessary.
9Re-inspect the spray nozzles
and visible heat transfer
section.

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Figure 3. Adjustable Motor Base
Extended Shutdown
Perform the following services whenever the unit is shutdown in excess of three days:
• If the unit is mounted on vibration isolators or isolation rails (by others), refer to the
manufacturer’s guidelines before loading/unloading weight from the unit.
• Disconnect, lock-out, and tag-out all fans and pump motors.
• Close the shut-off valve in the make-up water line (supplied by others) and drain all
exposed make-up water piping. Heat trace and insulate all exposed make-up piping
that will be exposed to freezing temperatures.
• Drain the cold water basin and all the piping (excluding the coils) that will be exposed
to freezing temperatures. Heat trace and insulate all exposed piping.
• To minimize the risk of biological contamination during shutdown, it is recommended
the entire system be drained, excluding the coils.
• Clean all debris, such as leaves and dirt, from the interior and exterior of the unit.
• Clean and flush the water distribution system and cold water basin with the basin
strainer in place.
• Leave the cold water basin drain open so rain and melting snow will drain from the
unit.
• Clean the basin strainer and re-install.
• Lubricate the fan shaft bearings.
• Apply a good quality, corrosion inhibiting grease, such as one of those recommended
for lubricating the fan shaft bearings, to the adjustable motor base and threaded rod.
• Inspect steel shafts and bushings, and if necessary, apply RUST VETO®to protect the
exposed surfaces of the steel shafts and bushings from corrosion.
• Inspect the protective finish on the unit. Clean and refinish as required. Refer to
“Corrosion Protection” on page 22 for more details.
• Lockout the fan motor starting device in the “OFF” position to ensure personal safety
in case of future inspection or service.
Prolonged Outdoor Storage
• Conduct the “Extended Shutdown” procedure above if the unit is installed.
• Ensure the cold water basin is fully drained and the drain is open.
• For storage prior to installation, all components (ladders and platforms) and
accessories, which sometimes ship inside the unit and are not a permanent fixture in
the basin, should be removed and stored indoors.
• Remove the bottom drain plug from the spray pump(s). Store the plug(s) in a marked
plastic bag and attach it to the spray pump(s) for future use.
• Remove and store fan belts (if supplied) indoors, keeping matched belts together. Tag
belts appropriately for future identification.
• For storage prior to installation, coils should be charged with nitrogen at 15 psi in the
factory. Dry coils are shipped from BAC charged with nitrogen.
• Installed units that have been piped but not filled do not require additional
precautions.
NOTICE: Covering the unit with
a clear plastic tarpaulin during
storage can trap heat inside the
unit and cause damage to the
PVC components. If units must be
covered during storage, an opaque,
reflective tarp should be used.
DANGER: Rotating equipment
will cause severe personal injury
or death to persons who come in
contact. Do not perform any service,
maintenance, or inspection on or
near the fans, motors, and drives,
or inside the unit without first
ensuring that the fans and pump
motors are disconnected, locked
out, and tagged out.
Unit Operation and
Storage
Start-Up Procedure
Start-Up
Extended Shutdown
Start-Up
Prolonged Outdoor Storage

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• Units (with coils) that have been installed and operated should remain filled. If the
unit is stored in a freezing climate, the coil must be protected from freezing. For
protection against coil freeze-up, BAC recommends the use of an inhibited glycol
solution. If protecting the coils with glycol is not possible, the galvanized steel coils
should be drained completely and capped once as much water and moisture is
removed from the coil as possible.
• For extended shutdown periods after start-up, coils should be charged with nitrogen
at 15 psi in the field and capped by adding a threaded connection or a welded cap.
Prior to start-up, bleed off the nitrogen, then cut off the caps so the coil connections
can be piped.
• Apply a good quality, corrosion inhibiting grease, such as one of those recommended
for lubricating the fan shaft bearings, to the adjustable motor base and threaded rod.
• Spray coat electrical component housings (if supplied) with a suitable protective
coating, such as Cosmoline®Weathershed, and individually cover them with plastic,
taking care to leave openings for free air circulation.
• Inspect the protective finish on the unit. Clean and refinish as required. Refer to
“Corrosion Protection” on page 22 for more details.
Motor Recommendations
BAC standard motors are designed for storage at ambient temperatures of -20ºF to 104ºF
(-28.9ºC to 40ºC). Prolonged periods of exposure above or below these specified conditions
could degrade components of the motor and cause malfunction or premature failure.
• Motors should be removed and stored inside whenever possible. When indoor storage
is not possible the motors must be covered with a loose fitting tarpaulin. Do not
use plastic/plastic film. This cover should extend below the motor and be secured;
however, it should not tightly wrap the motor. This will allow the captive air space to
breathe, minimizing formation of condensation.
• Care must also be taken to protect the motor from flooding or from harmful chemical
vapors.
• The storage area should be free from ambient vibration. Excessive vibration can cause
bearing damage.
• Precautions should be taken to prevent rodents, snakes, birds, or other small animals
from nesting inside the motors. In areas where they are prevalent, precautions must
also be taken to prevent insects from gaining access to the interior of the motor.
• If motors are not stored indoors in a controlled environment, some form of heating
must be utilized to prevent condensation from accumulating in the motor. This
heating should maintain the winding temperature at a minimum of 9ºF (5ºC) above
the ambient temperature of the room, keeping it from dropping below the dew point
where condensation could form inside the motor. If space heaters are supplied, they
should be energized. If none are available, single phase or “trickle” heating may be
utilized by energizing one phase of the motor’s winding with a low voltage. Request
the required voltage and transformer capacity from BAC. A third option is to use an
auxiliary heat source and keep the winding warm by either convection or blowing warm
air into the motor.
• Rotate the motor shaft monthly to redistribute bearing grease.
NOTICE: Draining the coil will not
completely protect the coil from
corrosion; some corrosion will still
occur.
DANGER: Rotating equipment
will cause severe personal injury
or death to persons who come in
contact. Do not perform any service,
maintenance, or inspection on or
near the fans, motors, and drives,
or inside the unit without first
ensuring that the fans and pump
motors are disconnected, locked
out, and tagged out.

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Maintenance Requirements
• Rotate all fans and motors shafts monthly by hand. Hand-turning will ensure that the
shafts and bearings rotate freely and will redistribute grease within the bearings.
• Inspect the cold water basin monthly to ensure that the drain is open and remove any
leaves or debris that may have accumulated in the cold water basin.
• Inspect axial fans prior to start-up and at least once annually to ensure that the blades
are tight and that there is no corrosion or damage. Do not energize the fans if there is
damage or significant corrosion of fan components. Loose fan blades could result in
fan failure and possible injury or equipment damage.
• At least quarterly, inspect the rust preventative coating on external machined surfaces
of the drive system, including motor shafts, fan shafts, and bushings. If necessary
re-coat the surfaces with RUST VETO®. Do not let the coating contact the sheave
grooves, belts or fan blades
Start-Up Preparation After Prolonged Storage
Start-up procedures after long periods of storage are just as important as pre-shutdown
procedures.
• Fan and pump motors should be thoroughly inspected and cleaned to restore them to
pre-storage condition.
• Inspect axial fan(s) prior to start-up to ensure that the blades are tight and that there
is no corrosion or damage. Do not energize the fan(s) if there is damage or significant
corrosion of fan components. Loose fan blades could result in fan failure and possible
injury or equipment damage.
• Reinstall all fan belts, motors, and drain plugs (as applicable), and remove all
protective coverings.
• For units stored prior to installation, conduct rigging procedures as directed in the
unit’s Rigging and Assembly Instructions.
• Perform an insulation test of motor windings to ensure satisfactory insulation
resistance.
• Conduct full start-up procedure as stated in the “Start-Up Procedure” on page 7. Be
especially thorough for cleaning and inspection prior to start-up.
Unit Operation and
Storage
Prolonged Outdoor Storage
Motor Recommendations
Maintenance Requirements
Start-Up Preparation After
Prolonged Storage

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HXV HYBRID COOLER
Detailed Component
Maintenance Procedures
2
Cold Water Basin
The process fluid to be cooled is circulated inside the tubes of the unit’s heat exchanger.
Heat flows from the process fluid through the coil to the spray water outside which is
cascading over the tubes. The spray water collects in the cold water basin, passes through
the suction strainer and is pumped back to the distribution system.The cold water basin is
constructed from one of the following materials of construction:
• Galvanized steel
• TriArmor®Corrosion Protection System
• Welded stainless steel (Type 304 or 316)
Water Levels
• The operating water level in the cold water basin will vary with system thermal load
(evaporation rate), the bleed rate employed, and the make-up water supply pressure.
• The make-up valve controls the operating level, which is maintained at the levels
shown in Table 2.
• Check the operating water level monthly, and readjust the float when necessary to
maintain the recommended operating level.
• Consult “Water Level Control” on page 19 for information on how to set and maintain
basin operating level.
Inspection & Maintenance
• At least quarterly inspect the cold water basin, and remove any trash or debris
accumulated in basin or on the strainer. If sediment has accumulated in the cold
water basin, drain, clean and flush the cold water basin with fresh water. This will
remove sediment which can collect in the basin during operation. If not removed,
sediment can become corrosive and cause deterioration of the protective finish of
metallic basins.
–When flushing the basin, leave the strainer in place to prevent the debris from re-
entering the system.
–Remove the strainer after the basin has been flushed.
–Clean and replace the strainer before refilling the basin with fresh water.
• Adjust the float to maintain the design operating level. See Table 2.
CAUTION: Openings and/or
submerged obstructions may exist
in the bottom of the cold water
basin. Use caution when walking
inside this equipment.
Table 2. Water Levels
Model Number At Overow Level (in.) At Operating Level (in.)
HXV-1212 and HXV-1218 14.5” 8”

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Fan
HXV units use axial fan(s). Thoroughly inspect the fan(s) for damaged or deteriorated fan
blades and replace the fan(s) if necessary.
Inspection & Maintenance
• If the unit is already in operation, while the fan is running, check for any unusual
noises or vibrations.
• With the fan off and the motor disconnected, locked out, and tagged out, check the
general condition of the fan:
–Inspect for any loose or missing bolts in the fan shaft bushing, the fan hub, and the
fan shaft bearing(s).
–Check the fan blades for looseness, first by twisting the blade by hand, and then by
moving the blade tip up and down. There should be no play or slippage.
–Inspect each blade for excessive scale build-up that could cause vibration.
–Check each blade in the area of the shank for cracks. If cracks are found, the fan
motor should be locked out of service until the fan is replaced. Contact BAC for
assistance.
• Tip Clearance: Check the clearance between the tip of the blade and the fan cowl. The
clearance should be within 5/16” to 1/2”.
• Blade Pitch: Check to ensure that the blades are all at the same pitch. If uncertain,
measure the pitch with an inclinometer. All blades should be within 1/2° of each
other.
• Rotation: Turn the fan by hand to ensure that it moves freely with no rough spots,
binding or other malfunctions that could cause vibration or fan motor overload. While
rotating the fan, check the blade tracking. All blades should track within a 1” band at
any single point around the cowl.
• Direction of Rotation: On initial start-up, or if the fan motor has been rewired, briefly
energize the fan motor and note the direction of rotation. It should rotate in the
direction indicated by the arrow on the fan cowl. On units with independent fan
motors, check the rotation of each fan.
• Operation: On initial start-up, run the fan in the manual position for several minutes
and check for any unusual noises or vibration.
NOTICE: Ensure the controls for
the fan and pump motors are set
to allow a maximum of six on-off
cycles per hour to prevent motor
overheating.
Detailed Component
Maintenance
Procedures
Cold Water Basin
Water Levels
Inspection & Maintenance
Fan
Inspection & Maintenance
DANGER: Rotating equipment
will cause severe personal injury
or death to persons who come in
contact. Do not perform any service,
maintenance, or inspection on or
near the fans, motors, and drives,
or inside the unit without first
ensuring that the fans and pump
motors are disconnected, locked
out, and tagged out.
Inspection & Maintenance
• At least quarterly inspect the cold water basin, and remove any trash or debris
accumulated in basin or on the strainer. If sediment has accumulated in the cold
water basin, drain, clean and flush the cold water basin with fresh water. This will
remove sediment which can collect in the basin during operation. If not removed,
sediment can become corrosive and cause deterioration of the protective finish of
metallic basins.
–When flushing the basin, leave the strainer in place to prevent the debris from re-
entering the system.
–Remove the strainer after the basin has been flushed.
–Clean and replace the strainer before refilling the basin with fresh water.
• Adjust the float to maintain the design operating level. See Table 2.

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Fan Drive System
BALTIDRIVE®Power Train and Independent Fan
The BALTIDRIVE®Power Train consists of a solid-
backed, multi-groove, neoprene/polyester belt rated
for cooling tower service, and corrosion resistant
sheaves. These components provide high reliability
with low maintenance requirements.
The independent fan option consists of one fan motor
and drive assembly for each fan to allow independent
operation, adding redundancy to models with more
than one fan.
The BALTIGUARD™ Fan System consists of two
standard single-speed fan motors and drive assemblies. One drive assembly is sized for full
speed and load, and the other is sized for approximately 2/3 speed and consumes only 1/3
the design horsepower. This provides motor redundancy and the greatest level of reliability.
Inspection & Maintenance
These drives require a periodic check of the belt condition and, when necessary, tension
adjustment. The recommended service intervals are as follows:
• Initial Start-up: Servicing is not required prior to initial unit start-up. The drive has
been tensioned and aligned at the factory.
• Seasonal Start-up: Readjust the belt tension (if required).
• Operation: After the first 24 hours of operation, readjust the belt tension on a new unit
start-up or installation of a new belt. Thereafter, check the belt condition monthly, and
adjust tension as necessary. Readjust tension at least once every three months.
NOTE: There should be no “chirp”
or “squeal” when the fan motor is
started.
Figure 5a. Belt Tension with a Straight Edge Figure 5b. Belt Tension with a Tape Measure
Figure 4. BALTIGUARD™ Fan System
DANGER: Rotating equipment
will cause severe personal injury
or death to persons who come in
contact. Do not perform any service,
maintenance, or inspection on or
near the fans, motors, and drives,
or inside the unit without first
ensuring that the fans and pump
motors are disconnected, locked
out, and tagged out.

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Detailed Component
Maintenance
Procedures
Fan Drive System
BALTIDRIVE®Power Train and
Independent Fan
• Belt tension check:
–Place a straight edge along the belt from sheave to sheave as shown in Figure 5a, or
use a tape measure as shown in Figure 5b, to measure belt deflection.
–Apply a moderate force by hand (approximately 40 lbs/275 kPa) evenly across the
width of the belt in the center of the span between the sheaves.
–There is adequate belt tension if the belt deflects between 1/4” and 3/8” as shown
in Figures 5a and 5b.
• Belt tension adjustment (if required):
–Loosen the lock nut on the motor base adjusting screw.
–Turn the motor base adjusting screw counterclockwise to tension the belt, or
clockwise to relieve belt tension. During adjustment of belt tension, rotate the drives
several times by hand to evenly distribute the tension throughout the belt.
–When the belt is properly tensioned, retighten the locking nut on the motor base
adjusting screw.
• Drive alignment check and adjustment:
–Check the drive alignment annually to ensure maximum belt life.
–Place a straight edge across the driver and the driven sheaves as shown in Figure 6a
NOTICE: Ensure the controls for
the fan and pump motors are set
to allow a maximum of six on-off
cycles per hour to prevent motor
overheating.
Figure 6a. Standard Drive Alignment
for standard drives and in Figure 6b for the BALTIGUARD™ Fan System.
–There should be no more than 1/16” deviation from four points of contact.
–If realignment is required, loosen the motor sheave and align it with the fan sheave.
Allow 1/4” for draw-up as the bushing screws are retightened.
Figure 6b. BALTIGUARD™ Fan System Drive Alignment

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Fan Motors
HXV Hybrid Coolers use cooling tower inverter duty, premium efficient, totally enclosed,
single-speed, single-winding, reversible ball bearing type motor(s).
Inspection & Maintenance
• Clean the outside of the motor at least quarterly to ensure proper motor cooling.
• After prolonged shutdowns, check the motor insulation with an insulation tester
prior to restarting the motor.
• Check motor voltage and current following start-up and every three months while
in operation.
Adjustable Motor Base (BALTIDRIVE® Power Train Only)
Coat the motor base slides and adjusting screws (refer to Figure 3 on page 8) prior
to start-up, every three months while in operation, and following shutdown. Use good
quality, corrosion inhibiting grease such as one of those recommended for lubricating
the fan shaft bearings.
Fan Motor Removal Instructions (For Units with the Motor Removal System Option)
If the motor has to be removed, follow the instructions below:
• Lockout and tag out fan and pump motors before entering the unit.
• Disconnect wiring from fan motor.
• Using the motor base adjusting screw, relieve tension from the drive belt and
remove belt
• Rotate the davit arm over the motor using 3/4” socket or wrench on the hex head
on the bottom of the davit.
• Attach a suitable lifting device of sufficient load capacity to the eye hook on the
davit arm.
• Attach the other end of the lifting device to the factory supplied lifting points which
are mounted on the motor. Verify that the lifting device is secure at all attachment
points.
• Position the lifting device to take up any slack, and to support the weight of the
motor with minimal movement when the motor mounting hardware is removed.
• Carefully loosen and remove motor mounting hardware.
• Remove the hardware and clips which fasten the removable grating section directly
below motor.
• Remove the grating section directly below the motor.
• Lower motor down to the internal walkway and remove the motor through unit
access door.
Fan Motor Installation Instructions (For Units with the Motor Removal System Option)
• Lock out and tag out fan motor, fan motor power supply, and pump motors before
entering the unit.
• Attach a suitable lifting device of sufficient load capacity to the eye hook on the
davit arm.
NOTICE: Ensure the controls for
the fan and pump motors are set
to allow a maximum of six on-off
cycles per hour to prevent motor
overheating.
DANGER: Rotating equipment
will cause severe personal injury
or death to persons who come in
contact. Do not perform any service,
maintenance, or inspection on or
near the fans, motors, and drives,
or inside the unit without first
ensuring that the fans and pump
motors are disconnected, locked
out, and tagged out.

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NOTE: List of brand names is for
identification only and are not
exclusive recommendations.
Detailed Component
Maintenance
Procedures
Fan Motors
Inspection & Maintenance
Adjustable Motor Base
Fan Removal Instructions
Fan Shaft Bearings
Inspection & Maintenance
• Remove the hardware and clips which fasten the removable grating section directly
below motor base.
• Remove grating section directly below the motor base.
• Attach the other end of the lifting device to the factory supplied lifting points which
are mounted on the motor. Verify that the lifting device is secure at all attachment
points.
• Lift the motor into place.
• Reinstall grating section directly below the motor using factory supplied hardware.
• Fasten the motor to the motor base using factory supplied hardware.
• Remove lifting device from motor and from davit arm.
• Rotate the davit arm so that it is out of the area immediately above the fan discharge.
• Install the driver sheave and bushing, and align the drives per the drive alignment
instructions.
• Apply RUST VETO®to the exposed motor shaft and bushing.
• Install the drive belt and tension it per the instructions on page 15.
• Rewire the motor.
• Verify that area is clear of tools and personnel.
• From a safe location,re-energize the motor and check for proper rotation per the start-
up instructions.
Fan Shaft Bearings
Two pillow block ball bearings support each fan shaft. Each bearing is equipped with a
lubrication fitting and a slinger/locking collar to keep out moisture. Extended lubrication
lines are provided for convenience.
Inspection & Maintenance
• Lubricate the bearings with a manual grease gun or BAC’s optional Automatic Bearing
Greaser. Do not use high-pressure grease guns because they may rupture the bearing
seals.
• For units equipped with extended lubrication lines, if re-greasing in colder ambient
temperatures, apply the grease more slowly to allow it to flow through the extended
lube lines without over-pressurizing them.
• Lubricate the bearings with one of the following compatible water resistant greases
which are suitable for ambient temperatures ranging from - 65ºF (-53.9ºC) to +250ºF
(121.1ºC).
–Amoco - Rycon Premium #3
–Chevron - SRI
–Citgo - Polyurea MP2™
–Conoco - Polyurea 2™
–Exxon - Polyrex®EM
–Exxon - Unirex N™
–MobilGrease®- AW2
–Shell - Gadus S2 V100 3
–Shell - Gadus S3 T100 2
–SKF - LGHP2™
–Unocal 76 - Unilife Grease™

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Heat Transfer Section
Inspect the coil surface. Any corrosion, damage, or obstructions must be corrected.
Fill & Drift Eliminators, Combined Inlet Shields, and CIS Hail Guards
HXV Hybrid Coolers contain polyvinyl chloride (PVC) fill with integral drift eliminators,
PVC combined inlet shields, and PVC drift eliminators located in the air path leaving the
prime surface coil. CIS hail guards are located on top of the unit, above the dry finned
coil, to protect the coil from hail damage. PVC material is impervious to rot, decay, rust,
and biological attack.
Inspection & Maintenance
Inspect the fill, eliminators, and combined inlet shields at least quarterly, and clean
them as described below. Inspect the CIS hail guards annually or after a hail event. The
inspection procedure is as follows:
• De-energize, lockout and tagout the fan motor(s) and the unit pump(s).
• Inspect the fill, eliminators, combined inlet shields and CIS hail guards for
obstructions, damage and fouling. Hail guard inspection requires safe access to the
top of the unit, which is provided by others.
• Remove any obstructions from the fill, eliminators, combined inlet shields, and
CIS hail guards.
• Remove any minor fouling chemically. Contact your local water treatment
consultant for advice. CIS Hail guards must be removed before cleaning, to avoid
contaminating the dry finned coil surfaces.
• Extensive fouling may require mechanical cleaning and flushing. Exercise care
when cleaning to avoid damage to the PVC components. Hail guards must be
removed before cleaning, to avoid contaminating the dry finned coil surfaces. See
page 30 for removal instructions.
• Lubricate the bearings as follows:
–Initial Start-up: Normally, no lubrication is required since the bearings have been
lubricated at the factory prior to shipment. However, if the unit has been stored at
the job site for more than three months, all fan bearings should be lubricated with
new grease before initial operation. When lubricating, purge the old grease from the
bearing by gradually adding grease until a bead of new grease appears at the seal on
the underside of the bearing. It is necessary to visually observe the bearing as new
grease is pumped through the extended grease lines.
–Seasonal Start-up: Purge both bearings with new grease prior to start-up.
–Operation: Purge bearings with new grease every three months or 2,000 hours of
operation, whichever comes first.
–Extended Shutdown: Purge bearings with new grease prior to any prolonged storage
or downtime, then again just before startup.