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22

(percent of flow) required to maintain different concentrations with various 
cooling ranges*:

*  Range = Difference between hot water temperature and cold water temperature.

EXaMPLE: 44.2 L/s circulating rate, 10°C cooling range. To maintain 4 

concentrations, the required blowdown is 0.467% or .00467 times 44.2 

L/s, which is 0.2 L/s. 

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.

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 
belt and bearing life. Keep belts free from foreign material which may cause 
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.

Maintenance

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Note

Summary of Contents for MARLEY MH MHF702

Page 1: ... Marley MH Fluid Cooler User Manual sea_05 116E ...

Page 2: ......

Page 3: ... 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 Indicates presence of a hazard which can cause severe personal injury death or substantial property damage if ignored Indicates presence of a hazard which will or can cause personal injury or pro...

Page 4: ...ate 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 tion of the fluid cooler we cannot be responsible for addressing those safety issues that are affected by the fluid cooler s ...

Page 5: ...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 ...

Page 6: ...uid 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 purp...

Page 7: ...luid cooler to supporting steel with 19mm 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 ...

Page 8: ...onnect switch the motor should be wired to main power supply through short circuit protection and a magnetic starter with overload protection 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 co...

Page 9: ...nd 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 31m feet a DV DT output filter is recommended to avoid damage to the motor 31mº distance is based on our field experience the VFD m...

Page 10: ...nual 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...

Page 11: ...areducer 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 Improper installation of the...

Page 12: ...ith 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 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 Ifequippedwithbeltdrivecheckthetorqueon...

Page 13: ...ntinue filling the system until the water reaches a level approximately 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 initi...

Page 14: ...f 7 0 to 7 6 The chlorine residual must be held at 4 to 5 mg L 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 w...

Page 15: ...he 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 ex ample a 11 C reduction in wet bulb may result in only a 8 C reduction in cold process fluid temperature 3 Fluid flow rate Increasing the process fluid flow rate L s will cause a slight elevation in cold pro...

Page 16: ...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...

Page 17: ...he minimum allowable cold process fluid temperature is estab lished at or near minimum heat load it should be safe for all operat ing conditions Having established the minimum allowable cold water temperature maintaining that temperature can be accomplished by fan manipula tion as outlined in Item 4 under Fluid Cooler Operation 2 As cold air enters the louvers it causes the water flowing over the ...

Page 18: ...rive Caution note on page 12 for fan speed change and reversing precautions 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 sy...

Page 19: ...Marley sales representative Operation Note Model Coil Volume Liters Model Coil Volume Liters MHF702__061 246 MHF705__061 890 MHF702__081 322 MHF705__081 1192 MHF702__101 397 MHF705__101 1476 MHF702__121 473 MHF705__121 1760 MHF702__062 284 MHF705__062 1079 MHF702__082 379 MHF705__082 1438 MHF702__102 454 MHF705__102 1779 MHF702__122 568 MHF705__122 2139 MHF703__061 322 MHF706__061 1476 MHF703__081...

Page 20: ...ed between 6 5 and 8 0 with hardness and alkalinity levels between 100 and 300 mg L expressed as CaCO3 Chlorine if used shall be added intermittently with a free residual not to exceed 1 mg L 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 fo...

Page 21: ...e 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 B...

Page 22: ...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...

Page 23: ...nd 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 Figure 1 Figure 2 LOOSEN HARDWARE MOTOR JACKING SCREWS SINGLE MOTOR...

Page 24: ...er 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 3mm of each other and level within 1 2 3mm in 305mm in order to not adversely affect belt and sheave life Alignment can be achi...

Page 25: ...result in a fall 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 pe...

Page 26: ...zer trays above the coil removing any accu mulated debris or scale 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 e...

Page 27: ... 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 ...

Page 28: ...n Draining the coil is not recommended draining promotes corro sion inside the coil tubes See protecting coil in Freezing weather on page 18 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 ...

Page 29: ...arings 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 ence with free rotation of the f...

Page 30: ...apability 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 h...

Page 31: ... x x Lube lines if equipped Check for oil leaks in hoses or fittings x R x Belt drive if equipped Fan shaft bearing lubrication every 3 mo every 3 months every 3 months Check and tighten support fasteners x Check shaft sheave and belt alignment x Check belt tension and condition x x Check sheave bushing fastener torque x Fan Check and tighten blade and hub fasteners x Check fan blade pitch and tip...

Page 32: ...unbalanced voltage Check voltage and current of all three lines against nameplate values Overload Check fan blade pitch See Fan User Manual Check for drag in fan drivetrain as from damaged bearings Wrong motor RPM Check nameplate against power supply Check RPM of motor and drive ratio Bearing overgreased Remove bearing reliefs Run motor up to speed to purge excessive grease Wrong lubricant in bear...

Page 33: ...shaft bearing Belt drive Grease bearings Scale or foreign substance in circulating water system Insufficient blowdown See Water Treatment section of this manual Water treatment deficiency Consult competent water treating specialist See Water Treatment section of this manual Cold water temperature too warm See Tower Operation Entering wet bulb temperature is above design Check to see if local heat ...

Page 34: ... 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 piping inlets and piping outlets Some optional accessories such as handrails ladders and ...

Page 35: ......

Page 36: ...1 OFF JALAN DAMANSARA 46350 PETALING JAYA MALASIA 60 3 7665 1018 spxcooling com In the interest of technological progress all products are subject to design and or material change without notice 2008 SPX Cooling Technologies SPX COOLING TECHNOLOGIES MALAYSIA Sdn Bhd ...

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