SPX Marley NC Series Installation Operation & Maintenance Download Page 31

31

troubleshooting

Trouble

Cause

Remedy

Geareducer noise

Geareducer bearings

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.

Gears

Correct tooth engagement. Replace badly worn gears. Replace gears 

with broken or damaged teeth

Unusual fan drive vibration

Loose bolts and cap screws

Tighten all bolts and cap screws on all mechanical equipment and 

supports.

Unbalanced driveshaft or worn 

couplings

Make sure motor and Geareducer shafts are in proper alignment and 

“match marks” properly matched. Repair or replace worn couplings. 

Rebalance driveshaft by adding of removing weights from balancing 

cap screws. See Driveshaft User Manual.

Fan

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

Worn Geareducer berarings

Check fan and pinion shaft endplay. Replace bearings as necessary.

Unbalanced motor

Disconnecdt load and operate motor. If motor still vibrates, rebalance 

motor.

Bent Geareducer shaft

Check fan and pinion shaft with dial indicator. Replace if necessary.

Fan noise

Blade rubbing inside of fan 

cylinder

Adjust cylinder to provide blade tip clearance.

Loose bolts in blade clamps

Check and tighten if necessary

Scale or foreign substance in 

circulating water system

Insufficient blowown

See “Water Treatment” section of this manual.

Water treatment deficiency

Consult compentent water treating specialist. See “Water Treatment” 

section of this maual.

Cold-water temperature too 

warm 

(see “Tower Operation”)

Entering wet-bulb temperature 

is above design

Check to see if local heat sources are affecting tower. See if surronding 

structures are causing recircuation of tower discharge air. Discuss 

remedy with Marley representative.

Design wet-bulb temperature 

was too low

May have to increase tower size. Discuss remedy with Marley 

representative.

Actual process load greater 

than design

May have to increase tower size. Discuss remedy with Marley 

representative.

Overpumping

Reduce water flow over tower to design conditions.

Tower starved for air

Check motor current and voltage to be sure of correct contract power. 

Repitch fan blades if necessary. Clean louvers, fill and eliminators. 

Check to see if nearby structure or enclosing walls are obstructing 

normal airflow to tower. Discuss remedy with Marley representative.

Excessive drift exiting tower

Distribution basins overflowing

Reduce water flow rate over tower to design conditions. Be sure hot 

water basin nozzles are in place and not plugged.

Faulty drift elimination

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 in place. Clear if necessary. 

Replace damaged or worn out components.

Summary of Contents for Marley NC Series

Page 1: ...NC steel cooling tower I N STALLATION OPE RATION MAI NTE NANCE Z0628276 rev A I SSU E D 05 2015 READ AND UNDERSTAND THIS MANUAL PRIOR TO OPERATING OR SERVICING THIS PRODUCT US E R MAN UAL...

Page 2: ...ng tower Carefully read the manual before installation or operation of the tower and follow all instructions Save this manual for future reference Indicates presence of a hazard which can cause severe...

Page 3: ...ranty If you have questions about the operation and or maintenance of this cooling tower and you don t find the answers in this manual please contact your Marley sales representative When writing for...

Page 4: ...ccess platform Tower Location Space available around the tower should be as generous as possible to pro mote ease of maintenance and to permit freedom of airflow into and through the tower If you have...

Page 5: ...es per cell The upper module includes hoisting clips at the top of the module The hoisting clips on the lower module are located near the bottom on the sides of the cold water basin All other models s...

Page 6: ...amsandfromthetopofthebottommoduleandremoveshipping cover from bottom of top module replace fasteners at side of module to preventleaks Placetopmoduleonthetopperipheralbearingsurface factory installedg...

Page 7: ...ropriately sized circular opening has been provided to accept a 125 ANSI B16 1 flat face flange connection Side outlet sump connection Unless otherwise specified sumps are manufactured of heavy duty F...

Page 8: ...place of the standard elbows normally required for inlet connection and 2 provide means of regulating flow to both sides of the tower Remove the center inlet flume assembly to gain access for attachm...

Page 9: ...t 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 windin...

Page 10: ...ied at reduced speeds To benefit from these advantages it is important that the drive be installed correctly Marley supplies VFD and VFD controls specifically designed for our cool ing products If you...

Page 11: ...models include a single piece fan guard NC8405 through NC8414 models include a two piece fan guard Models with extended velocity recovery cylinders do not have fan guards Improper installation of the...

Page 12: ...s 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 equipment Opera tion sho...

Page 13: ...that it is 75 open at that level Continue filling the system until the water reaches a level approximately 1 8 below the lip of the overflow If tower is equipped with a standard case face outlet conn...

Page 14: ...entoperation within these limits 6 Continue pump operation for about 15 minutes after which it is recom mended that the water system be drained flushed and refilled 7 While operating the condensing wa...

Page 15: ...cooling tower establishes only the cold water temperature attainable under any operating circumstance 2 Air wet bulb temperature Cold water temperature will also vary with the wet bulb temperature of...

Page 16: ...eraturebecomestoo cold switching the fan to half speed will cause the cold water temperature to rise stabilizing at a temperature a few degrees higher than before With a further reduction in water tem...

Page 17: ...below a mini mum allowable level say 36 F to 40 F If such low temperature operation is necessary or beneficial to your process establish the minimum allowable level as follows During the coldest days...

Page 18: ...on should not need to exceed 1 or 2 minutes Monitoring is required to determine the time required to melt accumulated ice Operating the fan in reverse at half speed for prolonged periods during subfre...

Page 19: ...ange of the internal riser and tap for a 20 bolt with sealing washer that will be used as a plug See figures below for drilling details Normally weep holes are plugged during tower operation and plugs...

Page 20: ...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 CaCO3 Chlorine if used shall be added inte...

Page 21: ...surfaces 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 Filtra tion devic...

Page 22: ...that secure the motor mount frame to the belt drive frame then loosen the retaining nuts on the two threaded rods and turn the threaded rods to apply proper tension Apply the same quantity of turns to...

Page 23: ...f 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 a...

Page 24: ...s recommended that you read them thoroughly Where discrepancies may exist the separate Service Manuals will take precedence The following is recommended as a minimum routine of scheduled mainte nance...

Page 25: ...pment by hand grease the bearings until a bead forms around the seals Mobil SHC 460 grease is recommended Semi Annually If equipped check the belt tension and condition If equipped check Geareducer oi...

Page 26: ...ctions Motor located outside plenum option Open and lock out disconnect switch to make certain motor cannot be started 1 Remove guard as shown Opposite end motor bearing is accessible from outside the...

Page 27: ...s a need to have the tower painted If relatively bright metal can be exposed by cleaning consider that the galvanizing has remained effective Unless there is evidence of a generalized failure of the g...

Page 28: ...eds and maintain consistently optimum thermal performance capability They are available by contacting your Marley sales representative Replacementparts Acompletestockofpartsandcomponentsismaintained a...

Page 29: ...es 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...

Page 30: ...anced 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 m...

Page 31: ...foreign substance in circulating water system Insufficient blowown See Water Treatment section of this manual Water treatment deficiency Consult compentent water treating specialist See Water Treatmen...

Page 32: ...safety cages may also require field installation If installation details are not covered in the NC Field Installation Manual a separate installation drawing or manual for each purchased option is inc...

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