Pentair 1900 Series Operating instructions

ENGLISH: PAGES 2-36
INSTRUCTION AND REPAIR MANUAL
NOTE! To the installer: Please make sure you
provide this manual to the owner of the equip-
ment or to the responsible party who maintains
the system.
Part #FM-03-529 | © 2018 Pentair plc. | 11/19/18
Model
1900 SERIES
FAIRBANKS NHUIS
INSTRUCTION AND REPAIR MANUAL
HORIZONTAL
SPLITCASE PUMPS
Model 1910
Model 1940
Models 1920 and
1920F

WARRANTY HIGHLIGHTS ...........................................3
INTRODUCTION ..............................................................5
GENERAL...................................................................5
CAUTION & SAFETY NOTICE .................................. 5–6
PUMP IDENTIFICATION ..............................................6
SAFETY NOTES...................................................... 6–7
HOUSEKEEPING.........................................................7
ENVIRONMENTAL CONDITIONS .................................7
STORAGE OF PUMPS......................................................7
GENERAL...................................................................7
CONSIDER A UNIT IN STORAGE ..................................7
SHORT-TERM STORAGE ........................................8
LONG-TERM STORAGE ..........................................8
THREE MONTHS TO ONE YEAR..............................8
OVER ONE YEAR................................................ 8–9
REMOVING FROM STORAGE .......................................9
INSTALLATION ..............................................................9
NET POSITIVE SUCTION HEAD (NPSH) ..................... 10
WET WELL DESIGN.................................................. 10
LOCATION AND HANDLING................................... 10–11
FOUNDATION ............................................................ 11
LEVELING OF THE UNIT ............................................ 11
GROUTING............................................................ 11-12
PIPING...................................................................... 12
INITIAL COUPLING ALIGNMENT ............................... 12
PERIODIC CHECK ..................................................... 13
AUXILIARY PIPING CONNECTIONS ........................... 13
ROTATION................................................................ 14
OPERATION.................................................................. 14
GENERAL................................................................. 14
OPERATING AT REDUCED CAPACITY ....................... 14
PRIMING................................................................... 15
STARTING THE PUMP............................................... 15
NORMAL OPERATION ...........................................15–16
STOPPING THE PUMP............................................... 16
NORMAL SHUTDOWN............................................... 16
EMERGENCY SHUTDOWN ........................................ 16
BEARING OPERATING TEMPERATURE ..................... 16
TROUBLESHOOTING .....................................................17
PUMP ...................................................................17–19
MOTOR ...........................................................20–21
REPAIR MANUAL .........................................................22
SERVICE ......................................................................22
LUBRICATION OF BEARINGS.............................. 22–23
REPAIRS ......................................................................23
DISASSEMBLY OF THE PUMP............................. 23–25
MECHANICAL SEALS..................................... 25–26
REASSEMBLY .................................................... 26–27
STANDARD PACKING...........................................27
MECHANICAL SEAL....................................... 27–30
STARTING PUMP AFTER REASSEMBLY.................... 31
ORDERING PARTS ............................................... 31-35
RECOMMENDED SPARE PARTS................................ 31
PREDICTED LIFE...................................................... 31
PARTS LIST..............................................................32
MISCELLANEOUS NUMBERED PARTS......................32
PUMP EXPLODED VIEWS.................................... 33–35
TABLE OF CONTENTS:

WARRANTY:
WARRANTY HIGHLIGHTS:
1. Seller warrants products of its own manufacture and workmanship under normal use and service according to
previously submitted terms and conditions letter or form KC585.
2. Accessories and components not manufactured by seller are warranted only to the extent of the original
manufacturer's warranty.
3. No allowances will be made for repairs or alterations effected without specific written authorization from seller.
4. Repairs or alterations made with other than genuine Fairbanks Nijhuis™ original equipment parts may void the
warranty and relieve the seller of all product responsibility.
5. This warranty is void unless the purchaser provides protective storage, installs and maintains the equipment in
accordance with manufacturer's instructions.
6. Under the terms of this warranty, seller shall not be responsible nor liable for:
a. Consequential, collateral or special losses or damages.
b. Equipment conditions caused by fair wear and tear, abnormal conditions of use, accident, neglect, or misuse of
said equipment.
c. Labor charges, loss or damage resulting from supplying of defective part(s) or improper repairs by unauthorized
person(s).
d. Damage caused by abrasive materials, chemicals, scale deposits, corrosion, lightning, improper voltage
or mishandling.
7. The above listed warranty highlights do not constitute our total terms and conditions regarding warranty.
3

1. Shipment
Was there any damage in transit?
Were all items received?
2. Storage
Has equipment been protected from inclement weather?
Was equipment subject to flooding?
Have all bearings been protected from moisture?
3. Installation
Were retaining fasteners, used in shipping, removed prior to installation?
Is grouting under base properly compacted?
Is grouting of the non-shrink type?
Have proper anchor bolts been used?
Have the bolts been properly tightened?
Have both the suction and discharge been checked for pipe strain?
Are lube lines and seal water lines properly installed?
Are accessory items, RTD’s, bearing temp detectors, vibration sensors, etc.
mounted and properly installed?
Are lube lines purged of air and lubricant added? (pump and driver)
Are all safety guards in place?
Have impellers been checked for proper clearance?
4. Alignment
Has the alignment of driver to pump been checked?
Have indicator readings been taken?
5. Rotation
Has the rotation of the drives been checked for correctness?
Has the coupling been turned to assure free rotation of pump and motor?
6. System
Has the system been checked to ensure that it is free ot foreign matter which
could be damaging to the pump?
Is liquid available to the pump?
Has assurance been obtained from responsible parties that all piping is secure
and that the routing of flow has been established and is correct?
7. Start-Up
Has flow been established?
Have gauge readings been taken?
Has packing been adjusted to ensure proper lubrication of packing?
If pumps are equipped with mechanical seals, is the lubricating seal water
pressure a constant 10 to 15 psi above the discharge of the pump?
Is excessive vibration present?
Is bearing operating temperature excessive?
PRESTART-UP AND START-UP CHECK LIST
Contractor Pump Serial Number
Project Name Pump Model Number
Procedure Yes No N/A Comments
Customer’s Representative
Witnessing Start-Up
Date
Company
Name
Date
Name
Fairbanks Nijhuis™ Pump Corporation
Representative Conducting Start-Up

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INTRODUCTION:
GENERAL:
Congratulations! You are the owner of the finest pump commercially available. If you give it the proper care as outlined
and recommended by this manual, it will provide you with reliable service and long life.
This manual contains information that is the result of engineering and research efforts. It is designed to supply adequate
instructions for the installation, operation and maintenance of your pump. Failure or neglect to properly install, operate
or maintain your pump may result in personal injury, property damage or unnecessary damage to
the pump.
These instructions apply to the pump only and have been prepared specifically for the pump supplied on this order. If your
operating conditions ever change, always refer to the factory for reapplication. Always refer to the manuals provided by
manufacturers of the accessory equipment for their separate instructions.
Variations exist in both the equipment used with these pumps and in the particular installation of the pump and driver.
Therefore, specific operating instructions are not within the scope of this manual but should be added by the parties
responsible for the operation of the entire station. The manual contains general rules and guidelines for installation,
operation and maintenance of the pump. If there are questions regarding the pump or its application, which are not
covered in this manual, please contact the factory as follows:
Fairbanks Nijhuis™
3601 Fairbanks Ave.
Kansas City, KS 66106
[phone]
For information or technical assistance on the drive source, contact the drive manufacturer local dealer or
representative.
To obtain additional data on hydraulics and pump selection and operation, we suggest you purchase both of the following
reference books:
A. Fairbanks Nijhuis Hydraulic Handbook available from the factory.
B. Hydraulic Institute Standards
Hydraulic Institute
9 Sylvan Way
Parsippany, NJ 07054-3802
CAUTION AND SAFETY NOTICE:
The installation, use and operation of this type of equipment is affected by various federal, state and local laws and the
regulations concerning OSHA. Compliance with such laws relating to the proper installation and safe operation of this
type of equipment is the responsibility of the equipment owner, and all necessary steps should be taken by the owner to
assure compliance with such laws before operating the equipment. In addition WARNING and CAUTION notes are located
throughout this manual. They should be read and observed.
The following symbols are used to alert maintenance personnel to procedures that require special attention or which
could damage equipment or could be dangerous to personnel.
CALIFORNIA PROPOSITION 65 WARNING:
This product and related accessories contain chemicals known to the State of California to cause cancer,
birth defects or other reproductive harm.

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DANGER:
Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.
WARNING:
Indicates a potentially hazardous situation which, if not avoided, could result in serious injury.
CAUTION:
Indicates that improper practices will result in equipment malfunction or failure.
NOTES:
Instructions that will aid in installation, operation, maintenance or that clarify a procedure.
PUMP IDENTIFICATION:
Pertinent nameplate information is shown below. It will aid in obtaining the correct replacement parts for your pump. The
serial number is stamped on the discharge flange.
Pump
Serial Number
Model Number
Pump Size
Number Stages
GPM
Head (feet)
*To be copied from motor nameplate.
SAFETY NOTES:
These warnings apply to pumps supplied by Fairbanks Nijhuis™. Refer to the manuals supplied by the driver or control
manufacturers for additional warnings before operating this equipment.
Before attempting to service this pump, familiarize yourself with this manual.
DANGER:
Disconnect or lock out the power source to ensure the pump will not start. Check with appropriate electrical
test equipment.
Do not attempt to service the pump until the electrical power has been disconnected and it has been verified that the
pump cannot start.
WARNING:
Certain procedures in disassembly and assembly require parts be heated to high temperatures. Heat resistant gloves
must be worn when handling heated parts. Heated parts can cause severe personal injury.
CAUTION:
After the pump has been installed make certain that the pump and all piping connections are tight and are properly
supported prior to start-up and operation.
Speed (RPM)
Driver
Manufacturer
Horsepower
Serial Number*
Full Load Amps
Phase / Hertz / Volts

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WARNING:
Do not operate the pump without the protective guards in place over the rotating parts. Exposed rotating parts can
catch clothing, fingers, or tools, causing severe injury to personnel.
CAUTION:
This pump is designed for the exclusive use of pumping water. It should not be used for pumping other media unless a
specific Purchase/Buyer agreement is negotiated.
WARNING:
Because many installations use automatic starting equipment, the pump unit may start at any time
without warning.
HOUSEKEEPING:
The area surrounding the pump installation area should be kept free of rags and debris. The area should be kept clean and
dry and should be checked periodically to ensure there is no water, oil or grease on the floor which could cause accidental
slippage of maintenance personnel.
The pump and driver should be kept clean. Any spillage of lubricants on the pump/driver during periodic maintenance
should be wiped clean. Loose ends of packing should be picked up and properly discarded after repacking the pump.
Drain lines should be checked to ensure they are functioning properly.
Driver ventilation ports should be kept free to ensure proper cooling of the motor.
ENVIRONMENTAL CONDITIONS:
Pumps are designed to operate in moderate to severe environmental conditions. Normally they should not be operated
in an ambient temperature exceeding 130°F or in conditions that would allow the sealing water or the pumped media to
freeze.
STORAGE OF PUMPS;
GENERAL:
If the equipment is not to be immediately installed and operated, store it in a clean, dry, well-ventilated place, free from
vibrations, moisture and rapid or wide variations in temperature.
Improper storage and preservation could damage the equipment which would result in non-warranty covered restoration
requirements or non-warranty covered product failures.
CONSIDER A UNIT IN STORAGE:
1. When it has been delivered to the job site and is awaiting installation.
2. When it has been installed but operation is delayed pending completion of construction.
3. When there are long (30 days or more) periods between operation cycles.
4. When the pump is shut down for periods of longer than 30 days.

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SHORT-TERM STORAGE:
Short-term storage is when the pump will be stored for periods not exceeding three months. The following are the short-
term storage requirements:
A. Rotate the shaft for several revolutions at least once every two weeks to:
1. Coat the bearing with lubricant.
2. Retard oxidation or corrosion.
3. Prevent possible false Brinelling.
LONG-TERM STORAGE:
Long-term storage is when the pump will be stored for periods exceeding three months. The following are long-term
storage requirements:
THREE MONTHS TO ONE YEAR:
1. Remove gland halves, packing and seal water ring from the stuffing box. Package them in a suitable container to
prevent loss or damage. Coat the inside of the stuffing box with grease.
• If the pump is equipped with a mechanical seal, remove the pipe plug in the stuffing box and pour at least 4
ounces of mineral oil into the seal housing. Reinstall the pipe plug.
2. Fill the bearing housings with specified lubricating grease until grease exits from relief fittings.
3. Wipe clean all exposed machined surfaces and coat with a heavy layer of grease or other equivalent rust
prevention material.
4. Cover the suction and discharge of the pump with cardboard or wood to prevent entry of foreign material
or varmints.
5. Rotate the pump shaft several times by hand repeating this every two (2) weeks during storage. Rotation of the
shaft will coat the bearings and retard oxidation, preventing possible false Brinelling.
OVER ONE YEAR:
1. Remove gland halves, packing and seal water ring from the stuffing box. Package them in a suitable container
to prevent loss or damage. Coat the inside of the stuffing box with grease.
• If the pump is equipped with a mechanical seal, remove the pipe plug in the stuffing box and pour at least 4
ounces of mineral oil into the seal housing. Reinstall the pipe plug.
2. Fill the bearing housings with specified lubricating grease until grease exits from relief fittings.
3. Clean all accessible machined surfaces to remove dirt, corrosion, grease and any other foreign matter. Clean
water passages to remove all foreign matter. Dry the pump to remove all moisture.
4. Spray flushing water and seal water piping with P-7 medium preservative oil. Seal all water inlet connections
with pipe caps or plugs.

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5. All internal surfaces in contact with water should be sprayed with Grade 5 of MIL-C-ISI73 Corrosion Preventive
Compound, solvent cut back. Drain all excess compound by removing drain plugs. Treat the drain plugs with P-I
or P-I9 preservative, replace and tighten.
6. Apply P-2 preservative to all exposed shaft surfaces.
7. Cover inlet and outlet nozzles with Grade A of MIL-B-I21 barrier material and a blank flange of mild steel
(1/16" minimum thickness), tempered hardboard (114" minimum thickness) or fully waterproofed plywood
(114" minimum thickness). Secure the flanges with at least 4 bolts with lockwashers.
8. Wrap the shaft, the frame and the stuffing box area with grease-proof barrier material, conforming to Type I,
Grade A of MIL-B-I2I. Secure the barrier with waterproof pressure sensitive tape.
9. Rotate the pump shaft several times by hand repeating this every two (2) weeks during storage. Rotation of the
shaft will coat the bearings and retard oxidation, preventing possible false Brinelling.
REMOVING FROM STORAGE:
After the storage period is over and prior to operating the pump, remove the cover on the thrust bearing housing for
inspection of the bearing lubricant. If any water or foreign matter is found in the lubricant, all bearings must be cleaned
and the lubricant replaced.
Refer to the Installation section of this manual for installation instructions.
After the pump has been set and grouted in place and is ready for operation, the following steps should be followed:
1. Reinstall the packing, seal water ring and gland. Adjust in accordance with this manual. Flush the mineral oil out of
the mechanical seal if unit is so equipped.
2. Remove bearing housing covers and remove one-half of the grease in bearing housings. Remove all grease relief
fittings and grease relief nipples from upper and lower bearing housings.
3. Start the pump per start-up instructions and permit grease to be purged from each bearing housing. Do not install
grease relief piping until purging has completely stopped after the pump has been in operation for at least eight (8)
hours. Observe bearing temperatures, and stop and start the pump or run it at reduced speed until temperatures
stabilize within the specified limits.
4. Stop the pump, wipe any grease off the shaft and bearing frame and place the pump in service per instructions in
this manual.
DANGER:
Do not attempt to clean the pump until electrical power has been disconnected and it has been verified that the pump
cannot start.
INSTALLATION:
Carefully read all sections of this manual and all other instruction manuals provided by manufacturers of other equipment
supplied with this pump.
Upon receipt of the shipment, unpack and inspect the pump and driver assemblies and individual parts to ensure none
are missing or damaged. Carefully inspect all boxes and packing material for loose parts to ensure none are missing or
damaged. Carefully inspect all boxes and packing material for loose parts before discarding them. Report immediately to
the factory, and to the transportation company involved, any missing parts or damage incurred during shipment, and file
your “damaged and/or lost in shipment” claim with the carrier immediately.

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NET POSITIVE SUCTION HEAD (NPSH):
NPSH can be defined as the head (energy) that causes liquid to flow through the suction pipe and enter the eye of the
impeller.
NPSH is expressed in two values:
1. NPSH required (NPSHR).
2. NPSH available (NPSHA).
It is essential that NPSHA always be greater than NPSHR to prevent cavitation, vibration, wear and
unstable operation.
NPSHR is a function of the pump design and therefore varies with the make, size, capacity and speed of the pump. The
value for your pump can be obtained from your pump performance curve or the factory.
NPSHA is a function of your system and may be calculated as follows:
A. When the source of liquid is above the pump:
1. NPSHA = barometric pressure (feet) + static suction head (feet)* – friction losses in suction piping (feet)
– vapor pressure of liquid (feet).
B. When the source of liquid is below the pump:
1. NPSHA = barometric pressure (feet) static suction lift (feet)* – friction losses in suction piping (feet)
– vapor pressure of liquid (feet).
*The datum elevation plane for horizontal pumps is the pump centerline.
WET WELL DESIGN:
Generally, it is required that an evenly distributed flow of non-aerated water be supplied to the pump suction. Improper
wet well or sump design or insufficient suction pipe submergence can result in intake vortexing which reduces the
pump’s performance and can cause severe damage to the pump.
We recommend that you secure the advice of a qualified Consulting Engineer for the analysis and design of the wet well.
Significant engineering data on wet well design is provided in the Hydraulic Institute Standards.
Upon request, Fairbanks Nijhuis™ will review plans and give general comments on the installation, but will not approve
such plans for a specific installation and will accept no responsibility or liability for the performance of the pump
intake structure.
LOCATION AND HANDLING:
The pump should be installed as near the fluid as possible so a short direct suction pipe can be used to keep suction
losses at a minimum. If possible, locate the pump so the fluid will flow to the suction opening by gravity. The discharge
piping should be direct and with as few elbows and fittings as possible. The total net positive suction head available
(NPSHA), which includes the suction lift and pipe friction losses, must be greater than the net positive suction head
required (NPSHR) by the pump.
The pump and driver should be located in an area that will permit periodic inspection and maintenance. Head and access
room should be provided and all units should be installed in a dry location with adequate drainage.

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WARNING:
Do not pick up the complete unit by the driver eye bolts or pump shaft.
FOUNDATION:
The pump foundation should have a level surface and be of sufficient mass to prevent vibration and form a permanent
rigid support for the unit. The most satisfactory foundations are concrete with anchor bolts of adequate size embedded
in the foundation in pipe sleeves with an inside diameter 2-1/2 times larger than the bolt diameter. This will allow for final
accurate positioning of the unit.
Recommended anchor bolt design is available from the factory.
LEVELING OF THE UNIT:
Lower the unit onto the foundation and position the base so the anchor bolts are aligned in the middle of the holes in the
base. Disconnect the coupling halves and do not reconnect until all alignment operations are complete.
Set the base on metal shims or metal wedges placed directly under the part of the base carrying the greatest weight, and
spaced close enough to give uniform support and stability.
Adjust the metal shims or wedges until the shaft of the pump and driver are level or vertical as appropriate and until pump
and driver shaft are aligned with each other. Make sure that all shims or wedges fit firmly between the foundation and the
base.
If leveling nuts are installed on the anchor bolts and are used for alignment, follow the same procedure as with shims
or wedges. Support the base with additional shims or wedges if necessary. Make sure that all nuts and shims are in firm
contact with the base. Tighten the foundation bolts snugly, but not too firmly, and recheck the shafts for alignment
before grouting.
GROUTING:
IMPORTANT:
The pump base must be set level to avoid any mechanical
difficulties with the pump or motor. The 1900 pump was
properly aligned, if supplied with a motor, at the factory.
However, since the pump base is flexible, it may spring
and twist during shipment. Do not pipe the pump until it is
realigned.
Grouting the base plate prevents lateral movement of the base
plate, and improves the vibration absorbing characteristics of
the foundation by increasing its mass. A wooden dam should be
constructed around the base plate to contain the grout while it is
being poured. The dam can be built tight against the base plate, or slightly removed from it as desired. Refer to Fig. 1. The
entire base plate should be completely filled with nonshrinkable type grout. Be sure to remove all air bubbles from the
grout.
CAUTION:
Damaging vibration may result if the base plate is not solidly in contact with the grout bed.
Do not fill the pipe sleeves with grout.
If leveling nuts are used, make sure they are not embedded in grout. Provide access in the grout to the leveling nuts so
that they can be backed off after the grout has cured.
SHIMS TO LEVEL BASE PLATE
WOODEN DAM
ON BOTH ENDS
TWISTED TENSION WIRE
ROLLED STEEL BASE
FOUNDATION BOLTS
SOUPY GROUT
Figure 1. Grouting the Base for Frame Mounted Pumps.

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Allow the grout to fully cure before backing off the leveling nuts (if used) and firmly tightening the foundation bolts. Then
recheck the alignment before connecting the piping as even the highest quality nonshrink grouts contract slightly during
drying.
PlPING:
IMPORTANT:
All piping connections must be made with the pipe in a free supported state, and without the need to apply vertical or
side pressure to obtain alignment of the piping with pump flange.
All piping should be independently supported near the pump so that pipe strain will not be transmitted to the pump
casing. The weight of the piping and of the contained liquid must be considered in support design. The suction and
discharge piping should be one or two sizes larger than the pump flange sizes, especially where the piping is of
considerable length. Any flexible joints installed in the piping must be equipped with tension rods to absorb piping axial
thrust.
The suction pipe must be airtight and sloped upward to the pump flange to avoid air pockets which will impair
satisfactory pump operation. The discharge pipe should be as direct as possible with a minimum of valves to reduce pipe
friction losses.
A check valve and closing valve should be installed in the discharge line and a closing valve in the suction line. The check
valve, between the pump and closing valve, protects the pump from water hammer and prevents reverse rotation in the
event of power failure. The closing valves are used in priming, starting and when the pump is shut down. The pump must
never be throttled by the use of a valve in the suction line.
INITIAL COUPLING ALIGNMENT:
Check safety codes, and always install protective guard or shield as required by the various federal, state and local laws
and the regulations concerning OSHA.
The pump and driver were accurately aligned at the factory. However, it is impossible to maintain this alignment during
shipping and handling. Therefore it will be necessary for you to realign the pump and driver. Flexible couplings are not
universal joints. They should not be used to compensate for misalignment of the pump and motor shafts. Their function
is to transmit power from the driver to the pump while compensating for thermal expansion and shaft end movement.
The coupling faces should be far enough apart so that they do not make contact when the motor shaft is forced to the
limit of the bearing clearance toward the pump shaft.
In order to properly align the coupling, you will need a taper gauge or set of feeler gauges, and a straight edge.
There are two types of misalignment encountered with flexible couplings: angular misalignment, in which the shafts are
not parallel, and parallel misalignment where the shafts are parallel but not on the same axis.
To check angular alignment, insert a feeler gauge or taper gauge at any four places 90° apart around the coupling halves.
Insert shims under the driver feet until the same reading is obtained at all four check points. The pump and driver will
then be in angular alignment.

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To check parallel alignment, a straight edge should be held against the edges of the coupling halves at any four places
90° apart around the coupling. The straight edge should be parallel to the pump and driver shafts at all times. Insert shims
until the straight edge lies flat against both coupling halves at all four checkpoints. The pump and driver will then be in
proper parallel alignment. Refer to Fig. 2.
For fine alignment, 3500 RPM operation, for all other coupler types.
A dial indicator should be used when greater alignment accuracy is required. Use the following alignment tolerances
unless specified otherwise by the coupling manufacturer. On sleeve type couplings make sure there is at least 1/8" end
clearance between the sleeve and the two coupling halves.
To check angular misalignments, mount the dial indicator base to the coupling half, and position the dial indicator button
on the front or rear face of the opposite coupling half. Set the dial to zero, rotate both coupling halves together, making
sure the indicator button always indicates off the same spot. Misalignment values within 0.004 inches TIR per inch of
coupler radius is permissible.
To check parallel misalignment, mount the dial indicator base to one coupling half, or shaft and position the dial indicator
button on the outside diameter of the opposite coupling half. Set the dial to zero. Rotate both coupling halves together,
making sure the indicator button always indicates off the same spot. Misalignment within 0.004 inches TIR is permissible.
PERIODIC CHECK:
Realign the base after piping from time to time while the unit and foundation are new. Coupling misalignment can occur
because of shifts in grouting, foundation or because of large objects going through the pump causing shock loading
conditions.
Coupling alignment should be checked periodically for changes. Coupling misalignment can lead to or cause bearing
failure, coupling failure, shaft breakage, high power consumption, etc.
AUXILIARY PIPING CONNECTIONS:
Install any additional piping connections your pump may require such as water seal piping, stuffing box drain, baseplate
drain, and pressure gauges.
NOTE:
For satisfactory pump operation and life, these auxiliary pipe lines must be kept clean.
STRAIGHT EDGE
PARALLEL MISALIGNMENT ANGULAR MISALIGNMENT
WEDGE OR
THICKNESS GAUGE
PERFECT ALIGNMENT
Figure 2. Flexible Coupling Alignment.

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Instruction and Repair Manual
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ROTATION:
Before connecting the motor to the pump, bump start the driver and verify rotation is in the proper direction. The correct
pump rotation is indicated by a directional arrow on the pump casing.
OPERATION:
GENERAL:
This section contains general rules for operation. Because variations may exist in a particular installation between the
pumps, the drivers and the accessory equipment, specific operating instructions are not within the scope of
this manual.
WARNING:
Before starting or operating the pump, read this entire manual and especially comply with the following instructions:
A. Before starting the pump, install guards around all exposed rotating parts.
B. Before starting the pump, rotate the unit or assembly by hand to assure all moving parts are free.
C. Observe all caution or danger tags attached to the equipment.
D. Never run the pump dry as the close running fits within the pump are lubricated by the liquid. Running dry may result
in pump seizure.
E. Before starting the pump, fill the casing and suction line with liquid. The pump may be primed by using a
priming system.
F. If excessive vibration or noise occurs during operation, shut the pump down and consult a Fairbanks Nijhuis™
representative.
G. Before starting a packed box pump, adjust the packing so there is sufficient leakage to lubricate the packing and
assure a cool stuffing box. (See maintenance instructions.)
OPERATING AT REDUCED CAPACITY:
In a typical application covering a wide range of flow rates, a variable speed driver is often used to adjust pump capacity,
and this is taken into consideration by Fairbanks Nijhuis when selecting the pump and impeller trim. Although these
pumps are applicable over a wide range of operating conditions, care should be exercised when doing so, especially
when the actual conditions differ from the sold-for conditions. You should always contact your nearest Fairbanks Nijhuis
distributor or factory before operating the pumps at any condition other than that for which they
were sold.
Generally, these pumps can be operated continuously at a capacity equal to 25% of the pump capacity at the best
efficiency point, and at higher capacities. At capacities less than 25% of best efficiency point capacity, we recommend
that the pumps be operated for intermittent periods of time only.

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PRIMING:
The priming procedure is different for positive and negative suction head systems and the following procedures should
be followed:
A. Positive suction head.
1. Open the vent on the highest point on the pump casing.
2. Open all suction valves.
3. Allow the liquid to flow from the vent hole until all air bubbles are vented, and then close the vent.
4. The pump is now primed.
B. Negative suction head.
1. Install the priming system on the vent on the highest point of the pump casing.
2. Close the discharge valve.
3. Open the suction valve.
4. Start the priming system.
5. Run the priming system until a continuous stream flows through the suction line, then close the valve to
the vent.
6. The pump is now primed.
STARTING THE PUMP:
A. After the pump is primed, and with the discharge valve closed and the suction valve open, start the driver according
to the driver manufacturer’s instructions.
B. Open the discharge valve slowly to prevent water hammer.
C. Immediately after the pump has been started, check bearing temperature, stuffing box lubrication and operation,
and pump noise level. Continue to monitor these values for the first several hours of operation.
NORMAL OPERATION:
Monitor the following during running cycles:
A. Unit vibration or noise.
B. Driver lubrication.
C. Pump lubrication.
D. Packing box leakage.

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Check the following before normal start-up:
A. Driver lubrication.
B. General condition of all equipment.
Start-up after a week or more downtime:
A. Repeat those procedures covered by initial start-up.
STOPPING THE PUMP:
Pump stations are usually designed to have the pumps started and stopped automatically using a controller. Since this is
a function of station design, the operators should be thoroughly familiar with the system’s operating parameters and in
the use of the controller. The general procedure to shut down the pump is as follows:
NORMAL SHUTDOWN:
A. Disconnect the electrical power.
1. Lock out the power to the driver.
DANGER:
Check power source with appropriate electrical test equipment to ensure driver cannot accidently start.
B. If the pump is to be removed for repair, close the suction and discharge valves.
EMERGENCY SHUTDOWN:
In the event of an emergency, shut off the power at the nearest switch. The operator or persons working around the
equipment should be familiar with locations of emergency shut-off points.
Many installations are equipped with emergency shut-off switches near the pump location. These locations should be
plainly marked and be readily accessible at all times.
The control panel (if used) may be equipped with an emergency stop button or switch.
BEARING OPERATING TEMPERATURE:
These pumps are designed to operate over a wide ambient temperature. The temperature, when measured on the
outside surface of the bearing housing, should not exceed 190°F. Temperatures in excess of 190°F may indicate
a lack of lubricant, or bearing problems. If the temperature exceeds this limit, the pump should be stopped and the cause
investigated and corrected.

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TROUBLESHOOTING:
PUMP:
Your Fairbanks Nijhuis™ pump has been engineered and carefully selected for your application. It should provide years of
trouble-free service. However, any piece of machinery is subject to wear and occasional malfunction.
To help you quickly isolate and rectify any malfunction, the following troubleshooting guide has been prepared.
Frequent use of the chart to determine the cause of minor operating problems may prevent a major problem or possible
breakdown of your pump.
TROUBLE PROBABLE CAUSE REMEDY
1. Pump fails to prime or loses its
prime. a. Air leaks in suction lines. a. Clean and tighten all suction prime connections; relocate
suction inlet in liquid source.
b. Suction strainer is clogged. b. Remove dirt, leaves, or other
material from the strainer.
c. Suction lift is too high. c. Re-evaluate pump requirements
and correct suction conditions.
d. Defective priming valve. d. Replace valve.
e. Defective packing or seal. e. Replace packing or seal.
2. No discharge from pump. a. Pump is not properly primed. a. Reprime the pump; refer to priming
troubles and remedies.
b. Total head is too high. b. Re-evaluate head calculations;
measure elevation differences
between pump and liquid source
and pump discharge point. Consult
your local Fairbanks Nijhuis sales
office.
c. Driver is not operating at rated
speed. c. Check voltage of electric motor; check steam pressure of steam
turbine; check engine RPM’s.
Refer to appropriate maintenance
manuals for possible troubles and
corrective action.
d. Impeller or discharge line is
clogged. d. Back flush pump to clear obstruction; disassemble pump
and/or piping and remove
obstruction.
e. Wrong direction of rotation. e. Check wiring against diagram
motor nameplate and in controller;
reverse any two power leads on a
three phase motor, replace a single
phase motor.
f. Pump is vapor bound. f. Provide additional pressure on
liquid being pumped by elevating
liquid source or pressurizing the
supply tank.

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TROUBLE PROBABLE CAUSE REMEDY
3. Pump does not deliver rated
capacity. a. Pump is not properly primed. a. See 2a above.
b. Suction lift is too high. b. See 1c above.
c. Excessive air in liquid. c. See 1a above.
d. Air leakage through stuffing box. d. See 1e above.
e.Driver is not operating at rated speed. e. See 2c above.
f. Impeller is clogged. f. See 2d above.
g. Wearing rings are worn. g. Replace wearing rings.
h. Impeller is damaged. h. Replace impeller.
i. Pump is vapor bound. i. See 2f above.
4. Insufficient pressure. a. Excessive air in liquid. a. See 3c above.
b.Driver is not operating at rated speed. b. See 2c above.
c. Wrong direction of rotation. c. See 2e above.
d. Total head is too high. d. See 2b above.
e. Wearing rings are worn. e. See 3g above.
f. Impeller is damaged. f. See 3h above.
g. Casing gasket defective allowing
internal leakage. g. Replace casing gasket.
h. Liquid is vaporizing. h. See 2f above.
5. Pump starts then stops pumping. a. Air leaks in suction line. a. See 1a above.
b. Air pockets in suction line. b. Reprime the pump; eliminate air
pockets.
c. Water seal line is plugged. c. Remove obstruction from water
line.
d. Excessive air in liquid. d. See 1a above.
e. Suction lift too high. e. See 1c above.
f. Defective packing or seal. f. See 1e above.
g. Pump is vapor bound. g. See 2f above.
6. Excessive power consumption. a. Speed is too high. a. Internal electric motor wiring is
incorrect; replace motor; refer
to applicable driver maintenance
manuals for possible troubles and
corrective action.
b. Wrong direction of rotation. b. See 2e above.
c. Total head is too high. c. See 2b above.
d. Total head is too low. d. Re-evaluate head conditions;
correct as required. Consult
your local Fairbanks Nijhuis™
sales office.
e. Impeller is clogged. e. See 2d above.
f. Impeller is binding. f. Relieve strain on casing; adjust
impeller clearance.
g. Motor shaft is bent or worn. g. Replace motor shaft.
h. Drive and pump are misaligned. h. Realign driver with pump.
i. Power frame shaft is bent or worn. i. Replace shaft.
j. Wearing rings are worn. j. See 3g above.
k. Packing is incorrectly installed. k. Install packing correctly.

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TROUBLE PROBABLE CAUSE REMEDY
7. Pump is noisy or has excessive
vibration. a. Magnetic hum. a. Consult motor manufacturer.
b. Motor bearings are worn. b. Replace bearings.
c. Foreign material in impeller. c. Remove foreign material.
d. Impeller is binding. d. See 6f above.
e. Motor shaft is bent or worn. e. See 6g above.
f. Drive and pump are misaligned. f. See 6h above.
g. Power frame shaft is bent. g. See 6i above.
h. Foundation is not rigid. h. Strengthen foundation; change
method of mounting pump unit.
i. Worn bearing in power frame. i. Replace bearing.
j. Impeller is damaged. j. See 3h above.
k. Lack of lubrication in power frame. k. Lubricate power frame bearing;
replace bearings if damaged.
l. Pump is not properly leveled. l. Check levelness of pump.
m.Piping is not supported. m. Provide support for suction and
discharge piping.
n. Pump is cavitating. n. Re-evaluate pump application;
consult local Fairbanks Nijhuis™
sales office.

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TROUBLE PROBABLE CAUSE REMEDY
1. Motor does not start. a. Break in power supply circuit. a. Close break in circuit.
1. Blown or defective primary fuses
or open circuit breakers. 1. Check voltage across all phases above the disconnect switch.
Replace fuses or reset circuit
breakers as necessary.
2. Blown or defective secondary
fuses or opened circuit
breakers.
2. Check voltage across all phases
below disconnect switch (with
disconnect switch closed).
Replace fuses or reset circuit
breakers as necessary.
b. Open control circuit. b. Complete control circuit.
1. Overload trips are open. 1. Push reset button.
2. Defective holding coil in
magnetic switch. 2. Push start button and allow sufficient time for operation
of time delay, if used, then
check voltage across magnetic
holding coil. If voltage is
measured, coil is defective. If
no voltage is measured, control
circuit is open.
3. Loose or poor connections in
control circuit. 3. Make visual inspection of all connections and retighten as
necessary.
c. Magnetic switch closes. c. Check switch operation.
1. Poor switch contact. 1. Open manual disconnect switch,
close magnetic switch by hand
and examine contactors and
springs.
2. Open circuit in control panel. 2. Check voltage at TI-TI-T3.
3. Open circuits in leads to motor. 3. Check voltage at leads to outlet
box.
4. Leads improperly connected. 4. Check lead numbers and
connections.
MOTOR:
The trouble or symptoms, their probable causes and the suggested remedies contained in this troubleshooting guide
will assist you in quickly determining and correcting most problems should they occur. It is not the intention of Fairbanks
Nijhuis™ to replace the recommendations of the motor manufacturer in regard to operation and maintenance. Rather,
this guide is offered as a supplement to such data. Any specific questions or problems should be directed to the
manufacturer of the motor. Be sure to supply the relevant data from the motor nameplate when inquiring about motor
service or maintenance.
DANGER:
Electrical troubleshooting should be performed by qualified electricians skilled in the use of electrical instruments.
Electrical power should be disconnected and locked to prevent the motor from accidentally starting during mechanical
systems check.