Marley MH Fluid Cooler
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User Manual 05-116E
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Contents
This manual contains vital information for the proper installation
and operation of your fluid cooler. Carefully read the manual before
installation or operation of the fluid cooler and follow all instructions.
Save this manual for future reference.
Note
Fluid Cooler Location ............................................................................. 5
Fluid Cooler Shipment............................................................................ 6
Receiving Fluid Cooler ........................................................................... 6
Hoisting Fluid Cooler.............................................................................. 6
Fluid Cooler Installation.......................................................................... 7
Motor Wiring........................................................................................... 8
Mechanical Equipment......................................................................... 11
Fluid Cooler Start-Up ........................................................................... 13
Fluid Cooler Operation ......................................................................... 15
Wintertime Operation ........................................................................... 16
Water Treatment ................................................................................... 20
Fluid Cooler Cleaning........................................................................... 21
Blowdown............................................................................................. 21
Belt Adjustment.................................................................................... 22
Sheave Alignment ................................................................................ 24
Fluid Cooler Maintenance .................................................................... 25
Seasonal Shutdown Instructions.......................................................... 28
Prolonged Shutdown............................................................................ 29
Troubleshooting.................................................................................... 32
Additional Information .......................................................................... 34
The following defined terms are used throughout this manual to bring at-
tention to the presence of hazards of various risk levels, or to important
information concerning the life of the product.
Indicates presence of a hazard which can cause severe personal
injury, death or substantial property damage if ignored.
Warning
Caution
Indicatespresenceofahazardwhichwillorcancausepersonalinjury
or property damage if ignored.
Indicatesspecialinstructionsoninstallation,operationormaintenance
which are important but not related to personal injury hazards.
Note
3
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Preparation
The Marley MH Fluid Cooler with CoolBoost™, purchased for this instal-
lation represents the current state of the art in crossflow, induced draft
fluid cooler design. Thermally and operationally, it is the most efficient
fluid cooler of its class.
These instructions—as well as those offered separately on motors, fans,
Geareducer®, couplings, drive shafts, float valves, pumps, etc.—are in-
tended to assure that the fluid cooler serves you properly for the maximum
possible time. Since product warrantability may well depend upon your
actions, please read these instructions thoroughly prior to operation.
If you have questions about the operation and/or maintenance of this
product, and you don’t find the answers in this manual, please contact
your Marley sales representative. When writing for information, or when
ordering parts, please mention product serial number shown on the name-
plate located on the access door.
Safety First
The location and orientation of the fluid cooler can affect the safety of those
responsible for installing, operating or maintaining the fluid cooler. However,
since SPX Cooling Technologies does not determine the location or orienta-
tionofthefluidcooler, wecannotberesponsibleforaddressingthosesafety
issues that are affected by the fluid cooler’s location or orientation.
WarNiNg
Thefollowingsafetyissuesshouldbeconsideredbythoseresponsible
for designing the tower installation.
Warning
• access to and from the fan deck
• access to and from maintenance access doors
• the possible need for ladders (either portable or permanent) to
gain access to the fan deck or maintenance access doors
• the possible need for handrails around the fan deck
• the possible need for external access platforms
• potential access problems due to obstructions surrounding the tower
• lockout of mechanical equipment
• the possible need for safety cages around ladders
• theneedtoavoidexposingmaintenancepersonneltothepotentially
unsafe environment inside the fluid cooler
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Preparation
Itisnotintendednorassumedthataccesstothefandeckonsingle-flow
Note
models—Models MHF702 thru MHF705—is needed or necessary.
Those are only some of the safety issues that may arise in the design
process.SPXstronglyrecommendsthatyouconsultasafetyengineer
to be sure that all safety considerations have been addressed.
Several options are available that may assist you in addressing some of
these personnel safety concerns, including:
• Louver face distribution basin access platform with ladder and handrail.
• Louver face redistribution basin level access platform with ladder and
handrail.
• A handrail system around the perimeter of the fan deck with either one
or two ladders for access to the deck. Double-flow models MHF706
and MHF707 only.
• Extended fan deck that provides additonal access around one end
of the fan cylinder opposite the fan deck access ladder. Double-flow
models MHF706 and MHF707 only.
• Ladder extensions—used where the base of the tower is elevated.
• Safety cages for ladders.
• External lube lines.
• Access door platform.
• Motor located outside the tower. Double-flow models MHF706 and
MHF707 with Geareducer drive only.
• External motor access platform. Double-flow models MHF706 and
MHF707 with Geareducer drive only.
• Plenum walkway. Double-flow models MHF706 and MHF707 only.
Standard on all other models.
• Mechanical equipment access platform.
Fluid Cooler Location
Space available around the fluid cooler should be as generous as possible
to promote ease of maintenance—and to permit freedom of airflow into
and through the fluid cooler. If you have questions about the adequacy
of the available space and the intended configuration of the fluid cooler,
please contact your Marley sales representative for guidance.
Prepare a stable, level support foundation for the fluid cooler, utilizing
weight, wind load, and dimensional information appearing on appropri-
ate Marley submittal drawings. Supports must be level to insure proper
operation of the fluid cooler.
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Installation
The fluid cooler must be located at such distance and direction to
avoid the possibility of contaminated fluid cooler discharge air be-
ing drawn into building fresh air intake ducts. The purchaser should
obtaintheservicesofaLicensedProfessionalEngineerorRegistered
Architect to certify that the location of the fluid cooler is in compli-
ance with applicable air pollution, fire and clean air codes.
Warning
Fluid Cooler Shipment
Unless otherwise specified, the MH Fluid Cooler ships by truck (on flat
bed trailers), which lets you receive, hoist, and install the tower in one
continuous operation. Single-cell single-flow fluid coolers ship on one
truck. Double-flow and multicell fluid coolers, depending on their size,
may require more than one truck.
Responsibilityfortheconditionofthefluidcooleruponitsarrivalbelongsto
the trucker—as does the coordination of multiple shipments, if required.
receiving Fluid Cooler
Prior to unloading the fluid cooler from the delivering carrier, inspect the
shipment for evidence of damage in transit. If damage is apparent, note
the freight bill accordingly. This will support your future recovery claim.
Find and remove the installation instruction drawings and bills of mate-
rial located in a plastic bag in the water collection basin. This information
should be kept for future reference and maintenance purposes.
Hoisting Fluid Cooler
All MH Fluid Cooler models must use hoist clips and overhead lifting for
handling assembled fluid cooler. Forklifting from base of fluid cooler
is not permitted. The clips for the top modules are located at the fan
deck level. The clips for the lower modules are located at the bottom of
the modules at the water collection basin. A Hoisting-installation label
which has hoisting dimensional information is located on the side casing
near the tower centerline. Remove tower from the carrier and hoist into
place according to the instructions on the label.
MH Fluid Cooler upper and lower modules must be hoisted and set
separately. Do not preassemble modules prior to hoisting.
Caution
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Installation
Hoisting clips are provided for ease of unloading and positioning the
fluid cooler. For overhead lifts or where additional safety is required,
safety slings should also be placed under the fluid cooler modules.
Under no circumstances should you combine the top and bottom
modules of modular models and attempt to hoist them at the same
time by utilizing the hoisting clips alone!
Warning
Fluid Cooler installation
These installation instructions are intended to help you prepare be-
fore your fluid cooler arrives. If discrepancies exist between these
instructions and those shipped with the fluid cooler, the instructions
shipped with the fluid cooler will govern.
Note
1. Prior to placement of the fluid cooler, confirm that the supporting
platform is level, and that the anchor bolt holes are correctly located
in accordance with Marley drawings.
2. Place bottom module on your prepared supports, aligning anchor bolt
holeswiththoseinyoursupportingsteel.Makesurethattheorientation
agrees with your intended piping arrangement. Attach fluid cooler to
supporting steel with 3⁄4" diameter bolts and flat washers (by others).
See support drawing for location and quantity. Position flat washers
between the bolt head and the fluid cooler basin flange.
3. Before setting top module in place on bottom module, clean any
debris from the underside of the top module fill, skid and beams and
from the top of the bottom module and remove shipping cover from
bottom of top module—replace fasteners at side of module to pre-
vent leaks. Place top module on the top peripheral bearing surface
(factory-installed gasket) of bottom module, aligning mating holes as
it is set in place. Attach top module to bottom module with fasteners
provided according to drawings shipped with your fluid cooler.
4. Connect the recirculation piping with rubber boot shipped with the
bottom module piping according to drawings shipped with you fluid
cooler.
5. Attach makeup water supply piping to appropriately-sized float valve
connection located in collection water basin side wall. Install the drain
and overflow according to drawings shipped with your fluid cooler.
If you wish to pipe overflow and drain water to a remote discharge
point, make those connections at this time also.
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Installation
Fastenersandcomponentsprovidedbyothersthataretobeattached
to the tower must be compatible with the cooling tower materials—
i.e. fasteners in a stainless steel cold water basin must be stainless
steel.
Note
6. Attach process fluid supply and return piping to the coil. Field piping
connection is an NPT male connection at the coil. A welded connec-
tion requires removing the threaded portion of the coil.
For welded connections protect adjacent areas from excessive heat
and sparks or damage may occur.
Caution
7. Wire motor(s) and recirculation pump(s) in accordance with wiring
diagram.
Formaintenance/safetypurposes, SPXCoolingTechnologiesrecom-
mendsalockouttypedisconnectswitchforallmechanicalequipment.
In addition to a disconnect switch, the motor should be wired to main
powersupplythroughshortcircuitprotection, andamagneticstarter
with overload protection.
Warning
Motor Wiring
Wire motor leads as shown on the motor nameplate matching the supply
voltage. Do not deviate from the motor nameplate wiring.
Either of following symbols may be shown on the motor nameplate –
Δ, Δ Δ
, Y, or YY. These symbols represent how the motor is constructed on
the inside and in no way have anything to do with a Delta or Wye electrical
distribution system serving the motor.
When using a starter:
• Set motor overload protection to 110% of motor nameplate amps.
This setting allows the fan motor to operate during cooler weather.
During cooler weather it is common for the motor to draw 6 to
10% higher than nameplate amps. High amps are common during
tower commissioning when the tower is dry and the ambient air
temperature is cool.
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Installation
• Do not start the motor more than six times per hour. Short cycling
the tower will cause fuses, breakers or O.L.s to operate and will
decrease motor life.
When using a two-speed starter:
• Motor rotation must be the same at slow speed and high speed.
• Single winding motor requires a starter with a shorting contactor.
• Two-winding motor requires a starter with out a shorting
contactor.
• All two-speed starters must have a 20 second time delay relay
when switching from high speed to low speed.
• Do not start the motor more than six times per hour (each low
speed start and each high speed start count as one start).
When using a VFD:
Before beginning, ensure that the motor is rated for “Inverter Duty”
Note
per NEMA MG-1, part 31.
• Set the VFD solid state overload protection to 119% of motor
nameplate amps and set “maximum current parameter” in the
VFD to motor nameplate amps. “Maximum current parameter” will
reduce fan speed and limit amp draw to nameplate amps during
cold weather operation. If furnished with a mechanical O.L. set this
at 110% over motor nameplate amps.
• Motor rotation must be the same in both VFD mode and By-pass
mode.
• If cable distance between the VFD and motor is greater than 100
feet a DV/DT output filter is recommended to avoid damage to the
motor. 100 feet distance is based on our field experience, the VFD
manufacture may state different distances and distance does vary
depending on the VFD manufacture.
• Program the VFD for variable torque output. Flux vector and con-
stant torque modes may damage the gearbox.
• Donotstartandstopthemotorusingthesafetyswitchatthemotor.
If the drive is being commanded to run and the load side is cycled
ON and OFF with the safety switch this may damage the VFD.
Using a VFD in cooling applications has advantages over traditional single
or two speed motor control. A VFD can reduce the cost of electrical en-
ergy being used and provide better temperature control. In addition, it
reduces the mechanical and electrical stress on the motor and mechanical
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Installation
equipment. Electrical savings can be large during periods of low ambient
temperature when the cooling requirement can be satisfied at reduced
speeds. To benefit from these advantages, it is important that the drive
be installed correctly.
MarleysuppliesVFDandVFDcontrolsspecificallydesignedforourcooling
products. If you have purchased a Marley VFD and/or controls package,
please follow the instructions in the User Manual for that system. Most
VFD problems can be avoided by purchasing the Marley drive system. If
you are installing a VFD other than the Marley drive, please refer to that
drives installation manual.
Improper use of a VFD may cause damage to equipment or personal
injury. Failure to correctly install the VFD drive will automatically void
all warranties associated with the motor and any equipment that is
either electrically or mechanically (directly) attached to the VFD drive
system. The length of this warranty avoidance will be contingent on
properly installing the VFD system and repairing any damage that
may have occurred during its operation. SPX Cooling Technologies
does not assume responsibility for any technical support or damages
for problems associate with non-Marley brand VFD systems.
Warning
Changing the operational fan speed from the factory settings could
cause the fan to operate in an unstable region which may result in
damage to the equipment and possible injury.
Warning
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Installation
Mechanical Equipment:
The fluid cooler is designed to operate at full speed and half speed.
Warranty is void if the tower is operated at speeds which cause
damaging vibrations to the tower and associated equipment. When
utilizing a variable frequency drive, the tower must be tested across
the full range of speeds and checked against CTI guidelines for ex-
cessive vibration. Speed ranges not meeting these guidelines must
be locked out in the VFD.
Warning
Warning
Always shut off electrical power to the tower fan motor prior to
performing any maintenance on the tower. Any electrical switches
should be locked out and tagged out to prevent others from turning
the power back on.
1. If equipped, check oil level in accordance with the Geareducer User
Manual for the Geareducer. (Although the Geareducer was filled to the
proper level at the factory, tipping during shipment and hoisting may
have caused some loss of oil.) If oil is required, fill Geareducer to the
proper level with approved lubricant. (See Geareducer User Manual )
Check oil level at the Geareducer or dipstick (standpipe located on fan
deck, if so equipped) to confirm that the proper level is indicated.
2. On double-flow models—MHF706 and MHF707—install fan cylinder
and two-piece fan guard according to the installation drawing shipped
with the fluid cooler.
Improperinstallationofthefancylinderandfanguardwilldestroythe
structuralintegrityofthefanguard.Failureofthefanguardcouldallow
operating or maintenance personnel to fall into the rotating fan.
Warning
3. Spin the fan(s) manually to assure that all fan blades properly
clear the inside of the fan cylinder. If equipped, observe the ac-
tion of the coupling (or drive shaft couplings) to be sure that the
motor and Geareducer are properly aligned. If necessary, cor-
rect the alignment in accordance with the included manual.
For belt drive equipped models observe the action of the sheaves and
belts to be sure that the motor is properly aligned with the fan sheave.
See Belt Tensioning and Sheave Alignment on pages 22 thru 24.
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Installation
It is essential that the fan cylinder and fan guard be installed in ac-
cordance with the drawings shipped with the tower. Do not force the
fan cylinder out of round.
Note
4. Momentarily bump (energize) the motor(s) and observe rotation of the
fan(s). If rotation is backwards, shut off the fan and reverse two of the
three primary leads supplying power to the motor.
If tower is equipped with a two-speed motor, check for proper rota-
tion at both speeds. Check also to see that starter is equipped with a
20 second time delay which prevents direct switching from high
speed to low speed. If the fan is intended to be reversed for deicing
purposes, make sure that the starter is equipped with a 2 minute
time delay between changes of direction. These delays will prevent
abnormal stress from being applied to the mechanical equipment
and the electrical circuit components.
Caution
5. Run the motor and observe the operation of the mechanical equip-
ment. Operation should be stable, and, if equipped, there should be
no evidence of oil leakage from the Geareducer.
6. Ifequippedwithbeltdrivecheckthetorqueonthefanandmotorsheaveafter
10 - 60 hrs. of operation. See Bushing Fastener Torque Values on page 25.
If the water supply system is not being operated—or if there is no
heat load on the system—motor amps read at this time may indicate
an apparent overload of as much as 10–20%. This is because of the
increased density of unheated air flowing through the fan. Determi-
nation of an accurate motor load should await the application of the
design heat load.
Note
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Operation
Fluid Cooler Start-Up
Amongothersources,outbreaksofLegionnaires’Diseasehavereport-
edlybeentracedtocoolingtowersandfluidcoolers.Maintenanceand
watertreatmentproceduresthatpreventamplificationanddissemina-
tion of Legionella and other airborne bacteria should be formulated
and implemented BEFORE systems are operated and continued
regularly thereafter to avoid the risk of sickness or death.
Warning
Water System:
1. New installations should be cleaned and treated with biocides by a
water treatment expert before startup.
2. Remove any and all accumulated debris from fluid cooler. Pay par-
ticular attention to inside areas of collection water basin, distribution
water basins, louvers and drift eliminators. Make sure that cold water
suction screens are clear and properly installed.
3. Fill the water system to an approximate depth of 8″ (203 mm) in the
depressedareaofthecollectionwaterbasin. Thisistherecommended
operating water level. Adjust the float valve so that it is 75% open at
that level. Continue filling the system until the water reaches a level
approximately 1/8″ (3 mm) below the lip of the overflow.
4. Start your pump(s) and check for proper rotation as indicated by
the arrow on the pump cover, observe system operation. A certain
amount of “pump-down” of the basin water level will occur before
water completes the circuit and begins to fall from the fill in the up-
per module. The amount of initial pump-down may be insufficient to
cause the float valve to open. However, you can check its operation
by pressing down on the operating lever to which the stem of the float
valve is attached.
Some trial and error adjustment of the float valve may be required to
balance the makeup water with tower operation. Ideally, the float valve
setting will be such that no water is wasted through the overflow at
pump shutdown. However, the water level after pump start-up must
be deep enough to assure positive pump suction.
5. Open the valve on the tower bleed line and adjust bleed to the recom-
mended rate. See Water Treatment section on page 20.
6. Continue pump operation for about 15 minutes, after which it is rec-
ommended that the water system be drained, flushed and refilled.
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Operation
7. While operating the recirculating water pump(s) and prior to operat-
ing the cooling tower fan, execute one of the two alternative biocidal
treatment programs described in the following:
• Resume treatment with the biocide which had been used prior
to shutdown. Utilize the services of the water treatment supplier.
Maintain the maximum recommended biocide residual (for the
specific biocide) for a sufficient period of time (residual and time
will vary with the biocide) to bring the system under good biological
control or
• Treat the system with sodium hypochlorite to a level of 4 to 5 mg/L
(ppm) free chlorine residual at a pH of 7.0 to 7.6. The chlorine re-
sidual must be held at 4 to 5 mg/L (ppm) for six hours, measurable
with standard commercial water test kits.
If the fluid cooler has been in operation and then shut down for a
duration of time and not drained, perform one of the two previous
biocidal treatment programs directly to the fluid cooler storage vessel
(collection basin, drain down tank, etc.) without circulating stagnant
water over the cooling tower fill or operating the cooling tower fan.
After biocidal pretreatment has been successfully completed, cooling
water may be circulated over the tower fill with the fan off.
Whenbiocidaltreatmenthasbeenmaintainedatasatisfactorylevelfor
at least six hours, the fan may be turned on and the system returned
to service. Resume the standard water treatment program, including
biocidal treatment.
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Operation
Fluid Cooler Operation
general:
The cold process fluid temperature obtained from an operating fluid cooler
will vary with the following influences:
1. Heat load: With the fan in full operation, if the heat load increases,
the cold process fluid temperature will rise. If the heat load reduces,
the cold process fluid temperature will reduce.
Heat Load (Btu/hr)
Range – °F
=
GPM x 500
Note that the number of degrees (“range”) through which the fluid
cooler cools the process fluid is established by the system heat load
andtheamountoffluidbeingcirculated,inaccordancewiththefollow-
ing formula—formula is only valid for 100% water as process fluid:
The fluid cooler establishes only the cold process fluid temperature
attainable under any operating circumstance.
2. air wet-bulb temperature: Cold process fluid temperature will also
vary with the wet-bulb temperature of the air entering the louvered
faces of the fluid cooler. Reduced wet-bulb temperatures will result
in colder process fluid temperatures. However, the cold process
fluid temperature will not vary to the same extent as the wet-bulb.
For example, a 20°F reduction in wet-bulb may result in only a 15°F
reduction in cold process fluid temperature.
3. Fluid flow rate: Increasing the process fluid flow rate (GPM) will cause
a slight elevation in cold process fluid temperature, while reducing
the fluid flow rate will cause the cold process fluid temperature to
decrease slightly. However, at a given heat load (see formula above),
process fluid flow reductions also cause an increase in the incoming
hot process fluid temperature and thermal range.
Under no circumstances should the recirculation water pump(s) be
cycled to control process fluid temperature. It is recommenced that
while process fluid is being circulated through the coil the fluid cooler
recirculation water system always be in operation.
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Note
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Operation
4. airflowrate:Reducingairflowthroughthefluidcoolercausesthecold
process fluid temperature to rise. This is the recommended method
by which to control leaving process fluid temperature.
If your fluid cooler is equipped with a single-speed motor, the motor
may be shut off when the process fluid temperature becomes too
cold. This will cause the process fluid temperature to rise. When the
fluid temperature then becomes too warm for your process, the motor
can be restarted.
When operating in this mode care must be taken not to exceed a total
fan acceleration time of 30 seconds per hour.
Caution
Fan cycling limits: From a dead stop, determine the number of sec-
onds it takes the fan to arrive at full speed. Divide this number into 30
to determine the allowable number of starts per hour. Considering the
normal fan and motor sizes utilized on MH Fluid Coolers, anticipate
that approximately 4 to 5 starts per hour are allowable.
If your fluid cooler is equipped with a two-speed motor(s), you will
enjoy greater opportunity for process temperature control. When the
process fluid temperature becomes too cold, switching the fan to
half-speed will cause the cold process fluid temperature to rise—
stabilizing at a temperature a few degrees higher than before. With a
furtherreductioninfluidtemperature,thefanmaybecycledalternately
from half-speed to off—subject to the same constraint of 30 seconds
of allowable acceleration time per hour as outlined above.
For greater insight on process fluid temperature control, please read
“Cooling Tower Energy and its Management”, Technical Report
#H-001-A, available at spxcooling.com.
Wintertime Operation:
The Marley film-fill system used in the MH Fluid Cooler has air entrance
louvers that are molded as an integral part of the fill. This feature makes
thesefluidcoolersveryforgivingofcoldweatheroperation, evenatthelow
temperature and reduced load conditions encountered in low temperature
applications.Nevertheless,duringoperationinsubfreezingweathertheop-
portunity exists for ice to form in the colder regions of the fluid cooler.
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Operation
Slushy, transitory ice forms routinely in the colder regions of the fill
of low temperature towers, and is visible through the tower louvers.
Such ice normally has no adverse effect on fluid cooler operation,
but its appearance should be a signal to the operator to undertake
ice control procedures.
Note
It is the operator's responsibility to prevent the formation of destruc-
tive (hard) ice on the fluid cooler fill. Certain guidelines should be
followed:
1. Do not allow the fluid cooler's leaving process fluid temperature to
drop below 45°F. If such low temperature operation is necessary or
beneficial to your process, establish the minimum allowable level as
follows:
Duringthecoldestdaysofthefirstwinterofoperation,observewhether
any ice is forming on the louver face, particularly near the bottom
part of the louver face. If hard ice is present on the louvers, you must
increase the allowable cold water temperature.
If the minimum allowable cold process fluid temperature is estab-
lished at or near minimum heat load, it should be safe for all operat-
ing conditions.
Caution
Having established the minimum allowable cold water temperature,
maintaining that temperature can be accomplished by fan manipulation,
as outlined in Item 4 under Fluid Cooler Operation.
2. As cold air enters the louvers, it causes the water flowing over the fill
to be drawn inward toward the center of the tower. Thus, under fan
operation,thelouversandlowerperipheryofthetowerstructureremain
partly dry, seeing only random splashing from within the tower—plus
normalatmosphericmoisturefromtheenteringair. Suchlightlywetted
areas are most subject to freezing.
Therefore, if excessive ice forms on the louvers, stop the fan for a few
minutes. With the fan off, the water flow will increase in the vicinity of
the louvers and reduce the ice buildup.
3. Under extended extreme cold conditions, it may be necessary to op-
erate the fan in reverse. This forces warm air out through the louvers,
melting any accumulated ice—adequate heat load must be available.
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Operation
Reversal may be at either full or half speed; however, reversal at half
speed is recommended. Reverse operation of the fan should be used
sparingly and should only be used to control ice, not to prevent it.
Reverse fan operation should not need to exceed 1 or 2 minutes. Monitor-
ing is required to determine the time required to melt accumulated ice.
Reverse operation of fans for prolonged periods during subfreezing
weather can cause severe damage to fans and fan cylinders. Ice can
accumulate inside fan cylinders at fan blade plane of rotation and
fan blade tips will eventually strike this ring of ice, damaging the fan
blades or cylinder. Ice can also accumulate on fan blades and be
thrown off, damaging fan cylinder or blades. Allow a minimum of 10
minutedelaybetweenreverseoperationandforwardoperationduring
subfreezing weather to permit ice to dissipate from fan blades and
fan cylinders. See Fan Drive Caution note on page 12 for fan speed
change and reversing precautions.
Warning
intermittent Wintertime Operation:
If periods of shutdown (nights, weekends, etc.) occur during freezing
weather, measures must be taken to prevent the water in the cold water
basin—and all exposed pipework—from freezing. Several methods are
used to combat this, including automatic basin heater systems and pump
freeze protection systems available from Marley.
Basin heaters systems will not prevent the coil from freezing.
Warning
Caution
Unless some means of freeze prevention is incorporated into your
system, the tower basin and exposed pipework should be drained at
the beginning of each wintertime shutdown period.
If tower basin is drained, verify that all basin heaters have been shut
off either by automatic cutoff or disconnect switch.
Warning
Protection against Coil Freezing:
Ethylene and propylene glycol solutions are the best means to protect the
coil from freezing. The following table provides the coil volume for each
MH Fluid Cooler model. MHF706 and MHF707 coil volumes are for both
coils added together.
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Operation
Coil Volume
Coil Volume
Model
Model
US Gallons
US Gallons
MHF702__061
MHF702__081
MHF702__101
MHF702__121
MHF702__062
MHF702__082
MHF702__102
MHF702__122
MHF703__061
MHF703__081
MHF703__101
MHF703__121
MHF703__062
MHF703__082
MHF703__102
MHF703__122
MHF704__061
65
MHF705__061
MHF705__081
MHF705__101
MHF705__121
MHF705__062
MHF705__082
MHF705__102
MHF705__122
MHF706__061
MHF706__081
MHF706__101
MHF706__121
MHF706__062
MHF706__082
MHF706__102
MHF706__122
MHF707__061
235
315
390
465
285
380
470
565
390
500
610
725
475
610
750
885
450
85
105
125
75
100
120
150
85
115
140
170
100
130
165
200
160
MHF704__081
MHF704__101
MHF704__121
MHF704__062
MHF704__082
MHF704__102
MHF704__122
210
260
310
190
250
315
375
MHF707__081
MHF707__101
MHF707__121
MHF707__062
MHF707__082
MHF707__102
MHF707__122
580
710
840
570
740
905
1071
When the use of industrial antifreeze solutions is not possible, the system
must be operated to meet both of the following conditions.
1. Maintain sufficient flow rate through the coil.
2. Maintain sufficient heat load on the process fluid. Fluid exiting the
coil must be maintained at or above 45°F. Cycling of the recirculation
pump should not be used to control process temperatures.
Draining the coil is not acceptable as a normal method of freeze
protection—draining promotes corrosion inside the coil tubes. Drain-
ing is acceptable in an emergency if the coil is not protected by an
antifreeze solution.
Caution
It is recommended that you discuss your freeze prevention options with
your local Marley sales representative.
19
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Operation
Water Treatment and Blowdown
Maintaining Water Quality:
The steel used in MH Fluid Cooler's has been galvanized with a heavy
zinc coating averaging 2.0 mils in thickness. Other materials used (PVC
fill, drift eliminators, and louvers, aluminum fans, cast iron Geareducer,
etc.) are selected to offer maximum service life in a “normal” fluid cooler
environment, defined as follows:
Recirculating water with a pH between 6.5 and 8; a chloride content (as
NaCl) below 500 ppm; a sulfate content (SO4) below 250 ppm; total al-
kalinity (as CaCO ) below 500 ppm; calcium hardness (as CaCO ) above
3
3
50 ppm; no significant contamination with unusual chemicals or foreign
substances; and adequate water treatment to minimize scaling.
• Startup Conditions: The water conditions during initial fluid cooler op-
eration are crucial in preventing premature corrosion of galvanized steel
(white rust). For at least the first eight weeks of operation, pH should
be controlled between 6.5 and 8.0 with hardness and alkalinity levels
between 100 and 300 ppm (expressed as CaCO ).
3
• Chlorine (if used) shall be added intermittently, with a free residual not
to exceed 1 ppm—maintained for short periods. Excessive chlorine
levels may deteriorate sealants and other materials of construction.
• An atmosphere surrounding the tower no worse than “moderate indus-
trial”, where rainfall and fog are no more than slightly acid, and they do
not contain significant chlorides or hydrogen sulfide (H2S).
• Many proprietary chemicals exist for control of scale, corrosion, and
biological growth and should be used prudently. Also, combinations
of chemicals may cause reactions which reduce treatment effective-
ness, and certain chemicals such as surfactants, biodispersants and
antifoams may increase drift rate.
The structure and coil of your fluid cooler consists primarily of
galvanized steel, therefore your water treatment program must be
compatible with zinc. In working with your water treatment supplier,
it is important that you recognize the potential effects on zinc of the
specific treatment program you choose.
Note
20
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Maintenance
Fluid Cooler Cleaning:
Any evaporative-type fluid cooler must be thoroughly cleaned on a
regular basis to minimize the growth of bacteria, including Legionella
Pneumophila, toavoidtheriskofsicknessordeath. Servicepersonnel
must wear proper personal protective equipment during decontami-
nation. Do NOT attempt any service unless the fan motor is locked
out.
Warning
Operators of evaporative cooling equipment, such as closed circuit cool-
ing towers, should follow maintenance programs which will reduce to an
absoluteminimumtheopportunityforbacteriologicalcontamination.Public
Health Service officials have recommended that “good housekeeping”
procedures be followed, such as: regular inspections for concentrations
of dirt, scale, and algae; periodic flushing and cleaning; and the following
of a complete water treatment program including biocidal treatment.
The visual inspection should take place at least once a week during the
operating season. The periodic flushing and cleaning should be done
before and after each cooling season, but in any event at least twice a
year. The louvers, drift eliminators, easily accessible fill surfaces and the
coil should be flushed by use of a moderate-pressure water nozzle, being
careful not to cause physical damage. A reliable water treatment program
should be installed and maintained. Filtration devices may be employed
to reduce the suspended solids concentrations, thus increasing the ef-
fectiveness of the water treatment program. See Fluid Cooler Startup
instructions on page 13.
Blowdown:
A fluid cooler cools water by continuously causing a portion of it to
evaporate. Although the water lost by evaporation is replenished by the
makeup system, it exits the tower as pure water—leaving behind its
burden of dissolved solids to concentrate in the remaining water. Given
no means of control, this increasing concentration of contaminants can
reach a very high level.
In order to achieve water quality which is acceptable to the fluid cooler, the
selected water treatment company must work from a relatively constant
level of concentrations. This stabilization of contaminant concentrations
is usually accomplished by blowdown, which is the constant discharge
of a portion of the circulating water to waste. As a rule, acceptable levels
on which to base a treatment schedule will be in the range of 2-4 con-
centrations. The following table shows the minimum amount of blowdown
➠
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Maintenance
(percent of flow) required to maintain different concentrations with various
cooling ranges*:
Number of Concentrations
Cooling Range
1.5X
2.0X
2.5X
3.0X
.18
.38
.58
.78
.98
4.0X
.11
.25
.38
.51
.64
5.0X
.08
.18
.28
.38
.48
6.0X
.06
.14
.22
.30
.38
5° F (2.78° C)
10° F (5.56° C)
15° F (8.33° C)
20° F (11.11° C)
25° F (13.89° C)
.78
.38
.25
1.58
2.38
3.18
3.98
.78
.51
1.18
1.58
1.98
.78
1.05
1.32
Multipliers are based on drift of 0.02% of the circulating water rate.
*
Range = Difference between hot water temperature and cold water temperature.
EXaMPLE: 700 GPM circulating rate, 18°F cooling range. To maintain 4
concentrations, the required blowdown is 0.458% or .00458 times 700
GPM, which is 3.2 GPM.
If fluid cooler is operated at 4 concentrations, circulating water will contain
four times as much dissolved solid as the makeup water, assuming none
of the solids form scale or are otherwise removed from the system.
When water treatment chemicals are added, they should not be in-
troduced into the circulating water system via the water collection
basin of the cooling tower. Water velocities are lowest at that point,
which results in inadequate mixing. An ideal location would be the
redistribution basin above the coil.
Note
Belt Tensioning
See Figure 1 and Figure 2 for MH Fluid Cooler models MHF702 thru
MHF705. Loosen specified hardware located at the top and bottom of
the motor support assembly before adjusting the jacking screws. Do not
remove the hardware—it is required to support the motor. Tighten the
hardware after adjustment. Ideal tension is the lowest tension at which
the belt will not slip under peak load conditions. Check tension frequently
during the first 24-48 hours of run-in operation. Overtensioning shortens
beltandbearinglife.Keepbeltsfreefromforeignmaterialwhichmaycause
slipping. Never apply belt dressing as this will damage the belt and cause
early failure. A Dodge® V-Belt Tension Tester is an alternate method for
tensioning V-belts. Check with you local belt supplier.
22
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Maintenance
LOOSEN HARDWARE
JACKING
SCREWS
MOTOR
Figure 1
SINGLE MOTOR—TWO FANS
See Figure 3 for MH Fluid Cooler models MHF706 and MHF707.The belts
areadjustedbyturningthethreadedrod.Beforetighteningorlooseningthe
belt, thedoublenutsholdingthemotorsupportinplacemust beloosened.
There are two jam nuts at the end of the rod next to the casing. Turn the
nut closest to the end of the rod to tighten the belt. Turn the other nut to
loosen the belt. After achieving proper tension tighten the double nuts
located on the fan side of the motor support against the motor support
to maintain belt tension, then retighten the motor support nuts. Ideal ten-
➠
JACKING
SCREWS
MOTOR
Figure 2
SINGLE MOTOR—SINGLE FAN
23
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Maintenance
sion is the lowest tension at which the belt will not slip under peak load
conditions. Check tension frequently during the first 24-48 hours of run-in
operation. Overtensioning shortens belt and bearing life. Keep belts free
from foreign material which may cause slipping. Never apply belt dress-
ing as this will damage the belt and cause early failure. A Dodge® V-Belt
Tension Tester is an alternate method for tensioning V-belts. Check with
you local belt supplier.
FAN SHAFT
SHEAVE
SHEAVE
Figure 3
STRAIGHT EDGE
Sheave alignment
• The motor sheave is to be positioned as close as possible to the motor
in order to minimize stress on the motor bushings.
• The motor and fan sheaves may have grooves that are not used. The
bottom surface of the motor and fan sheaves must be aligned within
1
⁄
8" of each other and level within 1⁄2° (1⁄8" in 12) in order to not adversely
affect belt and sheave life.
• Alignment can be achieved by placing a straight edge across the
sheaves making sure that it is level and measuring down to the bot-
tom surface of both sheaves at four points.
• The belt is to be located in the grooves closest to the motor center-
line.
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Maintenance
Bushing
Fastener
Torque ft·lb
ƒ
Bushing Fastener
Torque Values
1
⁄4
-
-
-
SH
SDS
SD
SK
SF
E
20
20
20
18
16
13
12
6
6
1
⁄4
1
⁄4
6
5⁄16
3
-
13
22
35
65
⁄
8
-
-
1
⁄2
9⁄16
-
F
Fluid Cooler Maintenance
Some maintenance procedures may require maintenance personnel to
enter the fluid cooler. Each cased face of the fluid cooler has a door for
access to the interior of the tower.
The optional fan deck ladder—models MHF706 and MHF707— is de-
signed and intended solely for personnel to gain access to the fan deck.
The fan deck ladder should not be used to enter or exit the access doors
located on the cased face of the tower unless the optional access door
platform is provided.
The purchaser or owner is responsible for providing a safe method
for entering or exiting the access door. Use of the fan deck ladder to
enter or exit the access doors may result in a fall.
Warning
Included with this instruction packet are separate User Manuals on each
major operating component of the tower, and it is recommended that you
read them thoroughly. Where discrepancies may exist, the separate User
Manuals will take precedence.
The following is recommended as a minimum routine of scheduled main-
tenance:
Always shut off electrical power to the tower fan motor prior to
performing any inspections that may involve physical contact with
the mechanical or electrical equipment in or on the tower. Lock out
and tag out any electrical switches to prevent others from turning
the power back on. Service personnel must wear proper personal
protective clothing and equipment.
Warning
➠
25
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Maintenance
Weekly: Inspect for bacterial growth and general operation conditions.
Bacterial growth should be reported to your water treatment expert for
immediate attention.
Monthly (Weekly at start up): Observe, touch, and listen to the fluid
cooler. Become accustomed to its normal appearance, sound, and level
of vibration. Abnormal aspects relating to the rotating equipment should
be considered reason to shut down the fluid cooler until the problem can
be located and corrected. Observe operation of the motor, coupling (or
drive shaft), Geareducer, if equipped and fan. Become familiar with the
normal operating temperature of the motor(s), as well as the sight and
sound of all components as a whole.
If equipped, check Geareducer oil level. Shut down the unit and allow 5
minutesfortheoilleveltostabilize.Addoilifrequired.CheckforGeareducer
oil leaks. Check the Geareducer as well as any optional oil lines to external
oil dipstick/sight glass.
Inspect louvers, drift eliminators and basin trash screens and remove
any debris or scale which may have accumulated. Replace any damaged
or worn out components. Use of high-pressure water may damage the
eliminator and louver material.
Observe operation of the float valve. Depress the operating lever to make
sure that the valve is operating freely. Inspect the suction screen for plug-
ging. Remove any debris that may have accumulated.
Check for any buildup of silt on the floor of the collection basin. Mentally
make note of the amount, if any, so future inspections will enable you to
determine the rate at which it is forming.
Every 3 months: If equipped, lubricate fan shaft bearings. While rotating
equipment by hand, grease the bearings until a bead forms around the
seals—a maximum charge of 0.30 ounces (MHF702-MHF704) and 1.4
ounces (MHF706-MHF707) is recommended. Mobil SHC 460 grease is
recommended.
Semi-annually: If equipped, check the belt tension and condition.
If equipped with dampers, lubricate jack shaft bearings and tiebar linkage
with silicone lubricant. If dampers are equipped with pneumatic or electric
actuators, the manufacturer's recommended maintenance procedures
should be observed. If dampers are exposed to heavy dust-laden air, oc-
casional flushing of the bearings with water is recommended.
Clean and disinfect cooling tower with biocides. Systems with biofouling,
high general bacterial counts, or positive cultures of legionella may require
26
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Maintenance
additional cleaning. Refer to “Fluid Cooler Cleaning” section—page 21.
Consult your water treatment expert as to prudent biological evaluation
testing.
Geareducer models used on MH Fluid Coolers are designed for 5-year
oil change intervals. To maintain five-year change intervals, use only
oil designed specifically for these Geareducers. If, after five years,
turbine-type mineral oil is used, the oil must be changed semiannu-
ally. Refer to the Geareducer User Manual for oil recommendations
and further instructions.
Note
annually: Relubricate motor(s) according to the manufacturer’s instruc-
tions. See instructions on the next page for towers with the motor located
outside the plenum option.
Check to see that all bolts are tight in the fan and mechanical equipment
region, including the fan cylinder and fan guard. Refer to Component User
Manuals for torque values.
Inspect the fluid cooler thoroughly, making maximum use of instructions
given in the separate user manuals. Check structural bolted connections
and tighten as required. Make preventive maintenance repairs as neces-
sary.
Check to see that all bolts are tight in the fan and mechanical equipment
region, including the fan cylinder and fan guard. Refer to Component User
Manuals for torque values.
Every5Years:Ifequipped,changeGeareduceroil.RefertotheGeareducer
User Manual for instructions.
Motor relubrication instructions
Motor located outside plenum option. Double-flow models MHF706 and
MHF707 only.
Open and lock out disconnect switch to make certain motor cannot
be started.
1. Remove guard as shown in Figure 4. Opposite end motor bearing is
accessible from outside the tower.
2. Remove grease fill and relief plugs at both shaft extension end and op-
posite end bearings and remove hardened grease, using clean wire.
➠
27
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Maintenance
Steel Side Casing
Motor
Grease Fill Plug
Attachment Screw
Guard
Figure 4
Grease Relief Plug
3. Insertgreasefittingsingreasefillopeningsandaddgreaseuntilgrease
is forced out through relief openings.
4. Replace fill plugs and operate mechanical equipment 30 minutes to
one hour to purge excess grease at grease relief opening.
5. Reinstall grease relief plugs and reinstall guard.
6. Resume normal fluid cooler operation.
Seasonal Shutdown instructions
When the system is to be shut down for an extended period of time, it is
recommended that the recirculation water system be drained. Leave the
basin drains open.
Draining the coil is not recommended—draining promotes corro-
sion inside the coil tubes. See protecting coil in Freezing weather
on page 18.
Caution
During shutdown, clean the fluid cooler (see Warning, page 21) and make
any necessary repairs. Eliminators and louvers are easily removed to gain
access to the coil. Pay particular attention to mechanical equipment sup-
ports and sheaves or coupling (or drive shafts).
Following each year’s shutdown and cleaning, inspect the fluid cooler’s
metal surfaces for evidence of the need to apply a protective coating. Do
not misinterpret grime as a need to have the tower painted. If relatively
bright metal can be exposed by cleaning, consider that the galvanizing
28
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Maintenance
has remained effective. Unless there is evidence of a generalized failure
of the galvanizing, localized touch-up should be all that is required.
To the extent that the galvanizing (zinc coating) still exists, paint will
not adhere to it readily. Contact the manufacturer of the coating you
intend to use for instructions.
Note
Fluidcoolerframework:Checkstructuralboltedconnectionsandtighten
as required.
Fans: Check fan assembly bolting and tighten as required. Use torque
values prescribed in the Fan User Manual.
Fans shaft bearings: If equipped, lubricate fan shaft bearings at close of
each operating season—see page 26.
Electric motors: Clean and lubricate motor at close of each operating
season (refer to motor manufacturer’s recommendations.) Check motor
anchor bolts and tighten as required. See Page 28 for fluid coolers with
motor located outside the plenum option.
Do not start motor before determining that there will be no interfer-
Caution
ence with free rotation of the fan drive.
The motor(s) should be operated for three hours at least once a month.
This serves to dry out windings and re-lubricate bearing surfaces (refer
to the Marley “Electric Motor User Manual” Manual 92-1475 available
at spxcooling.com.
At start of new operating season, make sure bearings are adequately
lubricated before returning motor to service.
Prolonged Shutdown
If shutdown period is longer than seasonal, contact your Marley sales
representative for additional information.
29
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Maintenance
SPX Cooling Technologies Services
Our interest in your MH Fluid Cooler does not end with the sale. Having
conceived, designed, and manufactured the most reliable and longest-
lasting fluid cooler of its class, we want to make sure that you gain the
maximum possible benefit from its purchase.
Therefore, the following services are available which are intended to: as-
sure the maximum possible service life under your operating conditions;
tailor the operating characteristics to your specific needs—and maintain
consistently optimum thermal performance capability. They are available
by contacting your Marley sales representative.
replacement parts: A complete stock of parts and components is main-
tained at one or more of the various Marley plants. In cases of emergency,
they can normally be shipped within 24 hours—by air freight if necessary.
However, you would obviously benefit from anticipating your need in ad-
vance, thus avoiding the cost of special handling.
Be sure to mention your fluid cooler serial number (from the fluid cooler
nameplate) when ordering parts.
Periodic maintenance: You may wish to contract with SPX Cooling for
regularly scheduled visits—for the purpose of inspecting and reporting
your fluid cooler’s condition—to make recommendations intended to
prevent emergencies— and to perform maintenance considered outside
the norm.
Thisserviceisnotintendedtoreplacetheimportantfunctionperformedby
your maintenance staff. Their attention assures the fluid coolers’s routine
operating performance, and is invaluable. However, we recognize that the
unusual manner in which a fluid cooler performs its function—as well as
the unique forces which act upon it—may be considerations which oc-
casionally require the services of an expert technician.
30
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Maintenance Schedule
Maintenance Service
Monthly
Semi-annually
Seasonal Startup or annually
Inspect General Condition and Operation
Observe Operation of:
x
x
Mechanical–motor, fan and drive mechanism
Makeup valve (if equipped)
x
x
x
x
x
x
Inspect for unusual noise or vibration
inspect and Clean:
Air inlet
x
x
x
x
x
x
x
x
PVC drift eliminators
Distribution basin, nozzles and collection basin
Fan and pump motor exterior
Coil surface
x
Check:
Collection water basin level
x
x
x
x
Blowdown–adjust as required
geareducer Drive (if equipped):
Check for loose fasteners including oil drain plug
Check oil level, check for / repair oil leaks
Change oil
x
x
x
R
x
Make sure vent is open
x
x
x
x
Check driveshaft or coupling alignment
Check for loose driveshaft or coupling fasteners
Check driveshaft or coupling bushings or flex element for unusual wear
Lube lines (if equipped):
x
Check for oil leaks in hoses or fittings
Belt drive (if equipped):
x
R
x
Fan shaft bearing lubrication (every 3 mo.)
Check and tighten support fasteners
Check shaft, sheave and belt alignment
Check belt tension and condition
Check sheave bushing fastener torque
Fan:
every 3 months
every 3 months
x
x
x
x
x
Check and tighten blade and hub fasteners
Check fan blade pitch and tip clearance
Check fan cylinder for loose fasteners
Motor:
x
x
x
Lubricate (grease as required)
Check mounting bolts for tightness
Operate at least
R
x
3 hours a month
3 hours a month
3 hours a month
Basin Heater (if equipped):
Check for proper operation of temp/low water level sensor
Inspect/clean buildup of contaminant from sensor
Structure:
x
x
x
x
Inspect/tighten all fasteners
x
x
Inspect and touch up all metal surfaces
R — Refer to Component User Manual
Note: It is recommended at least weekly, that the general operation and condition be observed. Pay attention
to any changes in sound or vibration that may signify a need for closer inspection.
31
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Troubleshooting
Trouble
Cause
remedy
Check power at starter. Correct any bad connections between the
control apparatus and the motor.
Check starter contacts and control circuit. Reset overloads, close
contacts, reset tripped switches or replace failed control switches.
Power not available at motor terminals
If power is not on all leads at starter, make sure overload and short
circuit devices are in proper condition
Wrong connections
Low voltage
Check motor and control connections against wiring diagrams.
Motor will not start
Check nameplate voltage against power supply. Check voltage at
motor terminals.
Open circuit in motor winding
Motor or fan drive stuck
Rotor defective
Check stator windings for open circuits.
Disconnect motor from load and check motor and fan drive for cause
of problem.
Look for broken bars or rings.
Check motor and attempt to start it. Motor will not start if single-
phased. Check wiring, controls and motor.
Motor running single-phase
Motor leads connected incorrectly
Bad bearings
Check motor connections against wiring diagram on motor.
Check lubrication. Replace bad bearings.
Check voltages and currents of all three lines. Correct if required.
Check and correct bracket fits or bearing.
Rebalance
Unusual motor noise
Electrical unbalance
Air gap not uniform
Rotor unbalance
Cooling fan hitting end belt guard
Wrong voltage or unbalanced voltage
Reinstall or replace fan.
Check voltage and current of all three lines against nameplate values.
Check fan blade pitch. See Fan User Manual. Check for drag in fan
drivetrain as from damaged bearings.
Overload
Check nameplate against power supply. Check RPM of motor and drive
ratio.
Wrong motor RPM
Remove bearing reliefs. Run motor up to speed to purge excessive
grease.
Bearing overgreased
Wrong lubricant in bearings
One phase open
Change to proper lubricant. See motor manufacturer's instructions.
Stop motor and attempt to start it. Motor will not stat if single-phased.
Check wiring, controls and motor.
Motor runs hot
Clean motor and check ventilation openings. Allow ample ventilation
around motor.
Poor ventilation
Winding fault
Check with ohmmeter.
Bent motor shaft
Insufficient grease
Straighten or replace shaft.
Remove plugs and regrease bearings.
Limit cumulative accelerations time to a total of 30 seconds/hour. Set
on/off or speed change set points farther apart. Consider installing a
Marley VFD drive for fine temperature control.
Too frequent starting or speed changes
Deterioration of grease or foreign material in grease Flush bearings and relubricate.
Bearings damaged
Replace bearings.
Check transformer and setting of taps. Use higher voltage on
transformer terminals or reduce loads. Increase wire size or reduce
inertia.
Voltage too low at motor terminals because of line
drop
Motor does not come up to
speed
Look for cracks near the rings. A new rotor may be required. Have
motor service person check motor.
Broken rotor bars
Wrong motor rotation
Wrong sequence of phases
Switch any two of the three motor leads.
32
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Troubleshooting
Trouble
Cause
remedy
If new, see if noise disappears after one week of operation. Drain flush,
and refill Geareducer oil. See Geareducer User Manual. If still noisy,
replace.
Geareducer bearings
Geareducer noise. (If
equipped).
Correct tooth engagement. Replace badly worn gears. Replace gears
with broken or damaged teeth.
Gears
Tighten all bolts and cap screws on all mechanical equipment and
supports.
Loose bolts and cap screws
Make sure motor and Geareducer shafts are in proper alignment and
"match marks" properly matched. Repair or replace worn couplings.
Rebalance drive shaft by adding or removing weights from balancing
cap screws. See Driveshaft User Manual
Unbalanced drive shaft or worn couplings. (If
equipped)
Make certain all blades are as far from center of fan as safety devices
permit. All blades must be pitched the same. See Fan User Manual.
Clean off deposit build-up on blades
Unusual fan drive vibration
Fan
Worn Geareducer bearings. (If equipped)
Worn fan shaft bearings. (Belt drive).
Check fan and pinion shaft endplay. Replace bearings as necessary.
Check fan shaft endplay. Replace bearings as necessary.
Disconnect load and operate motor. If motor still vibrates, rebalance
rotor.
Unbalanced motor
Bent Geareducer shaft. (If equipped).
Blade rubbing inside of fan cylinder
Loose bolts in blade clamps
Fan shaft bearing. (Belt drive).
Insufficient blowdown
Check fan and pinion shaft with dial indicator. Replace if necessary.
Adjust cylinder to provide blade tip clearance
Check and tighten if necessary.
Fan noise
Grease bearings.
See "Water Treatment" section of this manual.
Scale or foreign substance in
circulating water system
Consult competent water treating specialist. See "Water Treatment"
section of this manual
Water treatment deficiency
Check to see if local heat sources are affecting fluid cooler. See if
surrounding structures are causing recirculation of tower discharge air.
Discuss remedy with Marley representative.
Entering wet bulb temperature is above design
Design wet bulb temperature was too low.
May have to increase fluid cooler size. Discuss remedy with Marley
representative
Cold water temperature too
warm.
May have to increase fluid cooler size. Discuss remedy with Marley
representative
Actual process load greater than design
Overpumping
Reduce water flow rate over fluid cooler to design conditions.
See "Tower Operation."
Check motor current and voltage to be sure of correct contract
horsepower. Repitch fan blades if necessary. Clean louvers, fill and
eliminators. Check to see if nearby structures or enclosing walls are
obstructing normal airflow to fluid cooler. Discuss remedy with Marley
representative.
Fluid cooler starved for air
Reduce water flow rate over fluid cooler to design conditions. Be sure
distribution water basin nozzles are in place and not plugged.
Distribution basins overflowing
Faulty drift elimination
Excessive drift exiting fluid
cooler
Check to see that integral fill. Louvers and eliminators are clean, free of
debris and installed correctly. If drift eliminators are separate from fill,
make sure they are correctly installed and in place. Clean if necessary.
Replace damaged or worn out components
33
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Additional Information
increased load requirements: MH Fluid Coolers are designed so that
cells of either equal or unequal capacity can be added in the future. This
allows you to compensate for the load increases that normally occur with
the replacement or addition of production equipment—and still retain
continuity with respect to your fluid cooler system.
Fluidcoolerrebuilding:SPXroutinelyrebuildsandupgradesfluidcoolers
and cooling towers of all materials and manufacture. If your product ever
reaches the limit of its service life, we recommend that you investigate the
cost of rebuilding before you routinely order a new replacement tower.
Each MH Fluid Cooler includes a document package containing general
orientation drawings, and tower component manuals. These documents
contain important information relating to safe installation and operation
of the fluid cooler. Field installation is required for fan guards (double flow
models), pipinginletsandpipingoutlets. Someoptionalaccessories, such
as handrails, ladders and safety cages may also require field installation.
A separate installation drawing or manual for each purchased option is
included in the document package along with bills of material. If you have
purchased an option and can’t find the appropriate installation drawing,
contact your local Marley sales representative before proceeding.
In addition to these specific documents, numerous technical reports are
published by SPX including more detailed information on a variety of cool-
ing tower and fluid cooler operation and service topics. Your Marley sales
representativewillbehappytogiveyoucopiesofthesereportsatnocharge
or you can download copies from our website at spxcooling.com.
For complete parts and service assistance, contact the Marley sales
representative in your area. If you need help locating your representative,
please phone 800 462 7539 or check the internet at spxcooling.com.
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7401 WEST 129 STREET OVERLAND PARK, KANSAS 66213 UNITED STATES 913 664 7400 [email protected] spxcooling.com
In the interest of technological progress, all products are subject to design and/or material change without notice.
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©2008 SPX Cooling Technologies, Inc. Printed in USA
Manual 05-116E
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