Baltimore Aircoil Company equipment needs to be
properly installed, operated and maintained.Note: There should be no "chirp" or "squeal" when the fan motor is started. DRIVE ALIGNMENT
Proper drive alignment ensures maximum belt life. Alignment is
checked for standard drives after correct belt tensioning by placing
a straightedge across both sheaves as shown in the Figure below. When the drives are properly aligned the gap measured between
straightedge and sheave does not exceed 0,5 mm per 100 mm of
fan sheave diameter. 1. Motor Sheave
 2. Fan Sheave
 3. Points of Contact
LOCKING COLLAR
The excentric locking collar of the bearing at the drive end ensures
that the inner bearing race is secured to the fan shaft. Locking
collars can be set using the following procedure. (See Figure below)
1. Stop fan(s) and remove side access panel(s). 2. Loosen the set screw. 3. Using a drift pin centerpunch, tap the collar (in the hole provided)
tangentially in the direction of rotation while holding the shaft. 4. Retighten the screw. 5. Install access panel(s) and start fan(s). 1. Locking Collar
 2. Lubrication Fitting
 3. Extended Lubrication Line
ROTATION OF FAN(S) AND PUMP(S)
Fans must rotate without obstruction and both fans and pumps
must rotate in the correct direction, which is indicated by arrows on
the equipment. Check proper functioning as follows:
1. Stop fan(s) and pump(s). 2. Turn the fan by hand to ensure rotation without obstruction. Remove obstruction, if present. 3. Start the pump(s) and check for the proper rotation as indicated
by the arrow on the pump cover. If rotation is wrong, stop pump
and correct electrical wiring. 4. Start the fan(s) and check for proper rotation as indicated by the
arrow on the fan housing. If rotation is wrong stop fan(s) and
correct fan motor wiring. Belt Profile Diameter (mm)
Motor Sheave
Deflection Force (kg)
Min. Max. B 100 through 118
125 through 140
150 through 170
>180
1.5
1.5
2.0
2.5
2.0
2.5
2.5
3.0
Table 2: Belt Tension Forces
Figure 4: Fan Belt Check and Adjustment
Figure 5: Checking sheave alignment
Figure 6: Locking Collar Assembly
8
MAINTENANCE PROCEDURES
MOTOR VOLTAGE AND CURRENT
Check the voltage and the current of all three legs of the motors. The current should not exceed the nameplate rating. After
prolonged shutdown the motor insulation should be checked with a
megger insulation tester prior to restarting. 1. Insulation resistance test - minimum value should be 1 Mega
Ohm (1.000.000 Ohms). 2. Thermistors, if fitted, should be checked for continuity with a
multi-meter but never megger-tested. 3. Ensure supply voltage and frequency correspond to the motor
nameplate rating. 4. Ensure shaft turns freely. 5. Wire the motor in accordance with the wiring diagram as shown
on the motor nameplate and/or in the motor terminal box. 6. Turn on unit and check amp draw does not exceed nameplate
rating. Note: If motor is stored, it should be in a clean, dry place & have the shaft
rotated occasionally. Storage areas should not be subject to vibration. ! 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. When two speed motors are used, the motor
starter should include a 15 seconds time delay when switching from
high to low speed. DRIVE TRAIN
 1. Fan Sheave
 2. Belt
 3. Motor Sheave
The DRIVE TRAIN consists of a specially designed belt, a fan sheave
and a motor sheave. The high efficiency belt provides the premium
quality necessary for evaporative cooling equipment service. Together these components provide a highly reliable system with
low maintenance requirements. The DRIVE TRAIN should be
inspected periodically to check the belt tension, condition of the
sheaves and belt, and when necessary adjust the tension. The
recommended service intervals are specified elsewhere. Initial Start-up: If the equipment was supplied in assembled major
sections, no servicing is required prior to initial unit start-up since
the drive has been tensioned and aligned at the factory. If
equipment was supplied completely knocked-down (KD) then check
drive alignment & belt tensioning as per procedures outlined above. Seasonal Start-Up: Readjust the tension on the belt. Check
condition of sheaves. Operation: After initial unit start-up or the installation of a new belt,
the tension must be readjusted after the first 24 hours of operation. Thereafter the condition of the belt should be checked monthly and
the tension adjusted as necessary, but at least once every 3
months. ! No service work should be performed on the drive train without
first ensuring the fan and pump motors have been isolated,
tagged and locked in the off position. UNUSUAL NOISE AND VIBRATIONS
Unusual noise and/or vibration are the result of malfunctioning of
mechanical components or operational problems (unwanted ice
formation). If this occurs, a thoroughful inspection of the entire unit
followed by immediate corrective action is needed. If required,
consult your local BAC Balticare representative for assistance. GENERAL CONDITION OF THE EQUIPMENT
The inspection should focus on following areas:
- damage of corrosion protection
- signs of scale formation or corrosion
- accumulation of dirt an debris
- presence of biofilms
If there is evidence of scale formation (more than 0.1 mm) or
corrosion, water treatment regime must be checked and adjusted
by the supplier. Any dirt and debris need be removed following the CLEANING
PROCEDURE described in this manual (see page 12). If there is evidence of biofilms, the system, including piping, should
be drained, flushed and cleaned of slimes and other organic
contamination. Refill system with water and apply biocide shock
treatment. Check pH value and functionality of ongoing biocide
treatment. The RCT Cooling Towers are constructed of corrosion resistant
materials. The wet deck surface is made of en inert synthetic
material that requires no protection against rot, decay, rust or
biological attack. Other materials used in construction of the
equipment, that are listed below, should be inspected regularly. Stainless Steel Components
Stainless steel components should be inspected for sighs of
blemishes or corrosion and cleaned with stainless steel wool as
necessary. If more extensive corrosion is prevalent, contact you local
BAC-Balticare Representative. Fibreglass Re-Inforced Polyester (FRP) Components
FRP components should be inspected for accumulation of dirt and
cleaned with soap and water as necessary. Also FRP components
should be inspected for any penetration of gelcoat or veil. Such
penetrations should be repaired immediately. Figure 7: Drive Train
Inspections and Corrective Actions
MAINTENANCE PROCEDURES
9
HEAT TRANSFER SECTION
The fill should be inspected and cleaned at least quarterly or more
regularly if required by local authorities. The inspection procedure is as follows:
1. Shut off fan(s) and pump(s). 2. Remove the access panel. 3. Inspect the wet deck surface for
- obstructions
- damages
- corrosion
- fouling. Remove any obstructions from heat transfer section(s). Any damages or corroded areas need to be repaired. Call your local
BAC Balticare representative for assistance. Minor fouling can usually be removed chemically or by temporary
changes to the water treatment programme. Contact your water
treatment supplier for advice. Major fouling requires cleaning and
flushing according to the CLEANING PROCEDURES (See page 12). Regular checking of the total aerobic bacteria count (TAB) and
maintaining it within acceptable levels are the key to prevent
fouling. Note: When working on fill section or above fill section, fill bundle edges
should be protected from damage by service personnel, tools or debris by
placing a temporary cover of plywood, or other suitable material, over the top
of the fill bundles. DRIFT ELIMINATORS
The inspection procedure is as follows :
1. With fan(s) and pump(s) running visually check for areas with
excessive drift loss. 2. Shut off fan(s) and pump(s) and visually check eliminators for
- obstructions
- damages
- cleanliness
- proper fit
3. If any of the above problems have been observed, stop fan(s)
and pump(s) and remove eliminators. 4. Clean eliminators from debris and foreign matter. Remove dirt
and obstructions. Replace damaged or ineffective eliminators. 5. Install eliminators and ensure they fit tightly with no gaps. WATER DISTRIBUTION
The inspection procedure is as follows :
1. Shut off the fan(s), but leave the pump(s) running. 2. Check and adjust spray pressure, if required. 3. Remove the eliminators. 4. Check to see if the nozzles are producing the spray pattern
shown in figure(s) below
5. Clean water distribution from dirt and debris. Ensure spray
branches and nozzles are in place and clean. Replace damaged
or missing nozzles. 6. Install eliminators and ensure they fit tightly with no gaps. 7. Start fan(s) and pump(s). COMBINED INLET SHIELDS
Combined inlet shields are installed at the air inlet side. These will
prevent UV light from shining into the sump water and will eliminate
the suction of large airborne impurities and debris. In addition, they
will prevent water from splashing out of the air intake side of the
unit during fan cycling. Figure 8: Removable Fill
Figure 9: Removable Drift Eliminators
Figure 10: Nozzle Spray Distribution Type Cooling Tower
Figure 11: Removable Spray System
10
MAINTENANCE PROCEDURES
Inspect regularly and remove foreign objects that might impair air
passage. Replace broken and missing parts when necessary. Failure
to replace broken shields will result in water loss due to splash out. You can remove the Combined Inlet Shields by simple loosening a
single bolt on both ends of the air intake side. This allows simple
removal of the combined inlet shields in small and easy to handle
sections allowing full access to the sump section for maintenance. . Figure 12: Remove Combined Inlet Shields
FAN SHAFT
The fan shaft is fabricated from stainless steel. The exposed areas
of the fan shaft are coated with a soft seal for added corrosion
protection. It is recommended that the coating be inspected for
continuity quarterly or at least every 6 months. Any signs of surface
corrosion must be treated. This involves:
1. Removal of the protective coating with a suitable cleaning
medium
2. The removal of any surface corrosion with emery cloth
3. The re-coating of the shaft with soft seal. AXIAL FAN
Due to its size and speed, the axial fan has great potential for injury
and destruction if damaged. Inspect closely, and as required,
replace damaged or deteriorating fan blades. Inspection should
include the fan, fan cylinder and fan guard, and these should be
inspected for
- Fan blade tip clearance
- Pitch angle
- Bolt torque
- Excessive vibration
- Deterioration of fan assembly
Correct or adjust if necessary. Note: Before any disassembly, fan blades and hub should be match marked
to ensure proper blade pitch angle when reassembled. ! No service work should be performed on or near the fans,
motors, and drives or inside the unit without first ensuring the fan
and pump motors have been isolated, tagged and locked in the
off position. FAN MOTOR
The standard fan motor for this line of units is a TEFC (Totally
Enclosed Fan Cooled) motor. The motor with frame size smaller or
equal than 200L has permanently lubricated ball bearings and
special moisture protection on the bearings, shaft and windings. The only servicing required during operation is to clean the outside
surface of the motor at least quarterly to ensure proper motor
cooling. After prolonged shutdowns, the motor insulation should be
checked with a "megger" insulation tester before restarting the
motor.(Contact your local BAC Balticare representative
for advice.)
Whenever two speed motors are used for capacity control, a time
delay of at least 15 seconds is required when switching form high to
low speed. Sudden switch over might damage the drive system or
the motor. Note: When operating with VFD drives above nominal frequency be aware of
the potential risk for motor overload or mechanical damages. Note: It is recommended to provide sinus filters on the VFD to prevent bearing
damage on fan motors. ! Please refer to fan motor nameplate data when
programming a VFD. The purpose of a Low Level Cut out Switch is to protect the pump
from running dry in case of make-up failure or extreme water loss. The status of the alarm can be checked prior to pump start-up, but
should not be considered during the first minute after start-up, since
activation of the pump can cause a water level drop, that might
trigger the alarm. Normal make-up will stabilize the water level after
a short period of time. About Cold Weather Operation
Protection Against Sump Water Freezing
Capacity Control
6
MAINTENANCE PROCEDURES
COLD WATER BASIN AND BASIN STRAINERS
The cold water basin should be inspected regularly. Any debris
which may have accumulated in the basin or on the strainers should
be removed. Quarterly, or more often if necessary, the entire cold
water basin should be drained, cleaned and flushed with fresh water
to remove the silt and sediment which normally collects in the basin
and under the wet deck surface during operation. When flushing the basin, the strainers should be left in place to
prevent the sediment from re-entering the unit system. After the
basin has been flushed, the strainers should be removed, cleaned,
and replaced before refilling the basin with fresh water. ! DO NOT USE ACID TO CLEAN THE STRAINERS
Remote Basin
The water level in the basin of equipment designed for remote basin
operation is a function of the circulating water flow rate; water
outlet connection size, quantity and location, and outlet piping size
and configuration. The remote basin unit is supplied without a water
make-up assembly or a strainer and the basin operating level during
remote basin operation is not adjustable. OPERATING LEVEL AND MAKE-UP
As the water circulating through the tower is cooled, it collects in the
cold water basin and passes through the strainers into the system. The operating water level is controlled by the make-up valve and
should be maintained at an operating water level of 140 mm below
ledge on which louvres rest. Because the
typical winter load is less than the summer load, the winter
evaporation rate is frequently less than the summer evaporation
rate. With this reduced evaporation rate in winter, the water level in
the cold water basin will increase unless the float is readjusted. The
operating water level should be checked monthly and float readjusted as necessary to maintain the recommended operating
level. A float operated water make-up assembly is furnished as standard
equipment on cooling towers. It is located inside the unit within easy
reach from the access door. The float is mounted on an all-thread
rod which is held in place by wing nuts. The operating water level in
the cold water basin can be adjusted by repositioning the float and
all-thread rod using the wing nuts provided. The make-up assembly should be inspected monthly and adjusted
as necessary. The valve itself should be inspected annually for
leakage and the valve seat replaced if necessary. The make-up
water supply pressure should be maintained between 100 and 450
kPa for proper operation of the valve. To make the initial basin water level setting, fill the sump with water
until 2 cm above the operating level. Adjust the wing nuts of the
float ball so that the make-up valve is completely closed. Under normal load conditions
this setting should produce the correct operating level. At low load
conditions the operating level will rise and needs to be adjusted. The
unit basin should be closely monitored and water level adjusted as
necessary during the first 24 hours of operation. 1. Float Ball
 2. All Threaded rod
 3. Wing Nuts
 4. Float Arm Assembly
 5. Float Valve
BLOW DOWN
In case of a continuous blow down with a metering valve in the
bleed line, ensure that the valve is unobstructed and that blow down
water can drain freely. Measure the blow down flow rate by
recording the time needed to fill a given volume. For automatic blow down using conductivity control, ensure that the
conductivity probe is clean and that the blow down solenoid valve is
operational. Unless you have a specific adjustment procedure, your
water treatment company should check and adjust set points. Under no circumstances should sump heaters operate at other
times as they could potentially heat the water to temperature levels,
which are favourable to bacteriological growth. Ensure every six
months the heater thermostat is properly set and clean. Also ensure
that control and safety devices, such as low level cut out switches,
are operational, clean and properly incorporated into the control
circuit. ! SUMP HEATERS CAN BE HOT. BELT TENSIONING
Belt tensioning can be checked as follows:
1. 2. Rotate the fan sheave half a turn to evenly distribute the tension
in the belt before measuring. 3. Check belt tension by verifying both following conditions:
the deflection amounts 10 mm/m free belt length (see figure
below)
the deflection force required is between the minimum and
maximum values given in the table below.Figure 15: Ball Bearing
Shell Alvania grease RL3 -20?C to +120?C
Texaco Multifak Premium 3 -30?C to +140?C
Kluber Isoflex LDS Special A -50?C to +120?C
Mobil Mobilith SHC 100 -40?C to +175?C
Total Fina Elf Multis 3 -20?C to +120?C
Table 3: Grease Products
Figure 16: Ball Bearing
Figure 17: Adjustable Motor Base
12
MAINTENANCE PROCEDURES
MECHANICAL CLEANING
Keeping your evaporative cooling equipment (and the associated
system) clean will maintain its efficiency and help to prevent
uncontrolled bacteriological growth.For the cooling system, scale, corrosion and biological
control must be established and initiated when the system
is first filled with water and administered on a regular
basis thereafter in accordance with recognized Codes of
Practice, (such as EUROVENT 9 - 5/6, ACOP HSC L8, Guide
des bonnes pratiques, Legionella et tours
aerorefrigerantes, etc.).To facilitate servicing of the equipment, it is suggested that the
following parts be carried on hand :
- Make-up float ball (if applicable)
- Valve seal for water make-up valve
- Fan shaft bearings
- Spray nozzles and grommets
- Spray distribution branch grommets
- Set of belts
Insist on factory authorised parts to avoid loss of efficiency or an
operational risk, which may occur if non-authorised parts are used.On a quarterly
or six monthly basis check:
- electric connections
- motor protection devices
- check amp draw
- motor bearings for noise/overheating
- motor holding bolts
- external surface of motor for corrosion
If the motor is equipped with space heaters, these must be
activated when the motor is idle in order to prevent condensation
inside the motor.Cleaning Procedures
COMPREHENSIVE MAINTENANCE
13
In order to ensure maximum efficiency and minimum downtime of
your evaporative cooling system, it is recommended to establish
and execute a programme of preventive maintenance.Temperature increase due to sun radiation could
deform the fill or eliminators
AUTHORIZED PERSONNEL
The operation, maintenance and repair of this equipment should be
undertaken only by personnel authorized and qualified to do so. All
such personnel should be thoroughly familiar with the equipment,
the associated systems and controls and the procedures set forth in
this and other relevant manuals.Depending upon site
conditions it also may be necessary to install items such as bottom
screens, ladders, safety cages, stairways, access platforms,
handrails and toe boards for the safety and convenience of the
authorized service and maintenance personnel.Accordingly a treatment programme specifically designed to
address biological control should be initiated when the system is
first filled with water and administered on a regular base thereafter
in accordance with any regulations (national, regional) that may
exist or in accordance with accepted codes of good practice, such as
EUROVENT 9-5/6, VDMA Detailsheet 24649 etc.Consult your water treatment specialist
for specific recommendation
About Water Care
Pultruded Composite
pH 6.5 to 9.5
pH during initial passivation Not Applicable
Total hardness as (CaCO3) 750 mg/l
Total alkalinity as (CaCO3) 600 mg/l max.The preventive maintenance
programme must not only avoid that excessive downtime occurs
under unforeseen and unwanted conditions, but must also ensure
that factory authorized replacement parts are used, which are
designed to fit and for their purpose carry the full factory warranty.Passivation is the formation of a protective, passive, oxide layer on
galvanized steel surfaces.Motor Sheave
 4.!2.2.1.2.3.!!1.1.2.3.4.5.6.7.8.9.