Grundfos LM Series User manual

1
Series LM/LP
Single Stage In-Line
Centrifugal Pumps
Installation and Operating Instructions
Please leave these instructions with the pump for future reference.
Table of Contents:
Page #’s
Checking the Condition of the
Pump...................................... 2
Pre-Installation........................ 2
Installation Procedures........2-3
Electrical..............................4-5
Starting the Pump................5-6
Operating Parameters.........6-9
Troubleshooting.................9-13
Notes...............................14-15
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Checking the Condition of the Pump
Examine the components carefully to make sure no damage has occurred during shipment.
The Grundfos LM/LP pump should remain in its shipping carton until it is ready to be installed. This
carton is specially designed to protect it from damage. During unpacking and prior to installation,
care should be taken to ensure the pump is not dropped or mishandled. Immediately report in writ-
ing any damage to the transportation company and ask to have it inspected. Do not destroy packing
materials until shipment is inspected and the claim settled.
Pre-Installation Checklist
Before beginning installation procedure, check that the proper operating conditions for the
pump are present.
Is This The Correct Application For The Pump?
The Grundfos LM/LP series pumps are designed to handle a wide range of applications
including:
•Chilled and hot water circulation
•Condenser and cooling water circulation
•Water pressure boosting
•Pumping of water-glycol mixtures up to 50% solutions
• Solarthermaluids
•Other thin, clean, nonexplosive and non-greasy liquids
Maximum Operating Conditions
Temperature Ranges:
Minimum temperature: +5°F (-15°C)
Maximum temperature: 250°F (121°C)
Maximum Working Pressure: 175 PSI (12 Bars)
Installation Procedures
Select Pump Location
Thepumpshouldbelocatedinadry, well ventilated area which is not subject to freezing or extreme
variation in temperature. Care must be taken to ensure the pump is mounted at least six (6) inches
(152 mm) clear of any obstruction or hot surfaces. The motor requires an adequate air supply to
prevent overheating and should not be totally enclosed. For open systems requiring suction lift,
the pump should be located as close to the water source as possible to reduce pumping losses.
Pump Support
LM/LPpumpsaresuitableforoor,wallordirectpipelinemounting.Concreteorsimilarsolidfoun-
dationmaterialshouldbeusedforoormounting.Adequatesteelbracketsshouldbeusedforwall
mounting. The pipe on each side of the pump must be adequately supported for pipeline mounting.
The LM/LP pumps (except 3.0 LP6 and 4.0 LP5) have two tapped holes in the bottom of the pump
housing to allow the pump to be secured to a mounting bracket. Make sure the pump is secure to
themountingbracketandthemountingbracketisrmlyattachedtotheoororwall.
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Pipework
Arrowsontheangesofthepumpvoluteindicate
the ow direction of water through the pump.
GrundfosLM/LPmodelpumpscanbemountedin
eithertheverticalorhorizontalposition.The pump
can be installed with the motor in all positions be-
tween vertical and horizontal but the motor/pump
shaft must never fall below the horizontal plane.
See Figure 1. In open systems, install suction
piping to minimize friction losses and avoid air
pockets. See Figure 2. Size discharge piping to
reduceuidvelocitiesandminimizefrictionlosses.
It is suggested that isolation valves be installed on
eachsideofthepumptoavoiddraining the system
if the pump needs to be cleaned or repaired. It is
also suggested that a check valve be installed in
thedischargepipe.Apluggedteeorcappedpipe
should be mounted in the suction line to ll the
pump and pipe before start-up especially if the
system is not pressurized.
The pump and/or piping should be adequately supported on both sides to reduce thermal and me-
chanicalstressesonthepump.Ifpumps are installed close tonoisesensitiveareas,itisadvisableto
use pump and piping vibration isolators to prevent vibration from being transmitted to the structure.
Abypassorpressurereliefvalveshouldbeinstalledinthedischargepipeifthereisanypossibility
the pump may operate against a closed valve in the discharge line. Circulation through the pump
isrequiredtoensureadequatecoolingandlubricationofthepump.SeeTableAforminimumow
rates. The bypass should be routed back to a heat dissipating source or to a drain depending on
the liquid being pumped and local codes. Control of the bypass can be made by using a pressure
relief valve or thermostatic control valve.
Figure 2 - Suction Piping
Installation Procedures
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Electrical
All electrical work should be performed by a qualied technician in accordance with the
latest edition of the National Electrical Code, local codes and regulations.
WARNING
THESAFEOPERATIONOFTHISPUMPREQUIRESTHATITBEGROUNDEDINACCOR-
DANCEWITHTHENATIONALELECTRICALCODEANDLOCALGOVERNINGCODESOR
REGULATIONS.CONNECTTHEGROUNDWIRETOTHEGROUNDINGSCREWINTHE
TERMINALBOXANDTHENTOTHEACCEPTABLEGROUNDINGPOINT.
DO NOT START THE PUMP (EVEN TO CHECK THE DIRECTION OF ROTATION) UNTIL IT
HAS BEEN FILLED WITH WATER. Severe damage may be caused to the pump if it is run dry.
Figure 3- Motor Terminal Box Positions (Top View)
Motor
Grundfos LM/LP Pumps are supplied
withheavy-duty1750RPM(LMMod-
els)or3450RPM(LPModels),O.D.P,
NEMACframemotorsselectedtoour
rigid specications. T.E.F.C. motors
are also available. Motors for other
voltages and frequencies are available
on a special order basis.
Position of
Terminal Box
The motor terminal box can be turned
to any of four positions in 90° steps. To
rotatetheterminalbox,remove the four
bolts securing the motor to the pump
(do not remove the shaft coupling),
turn the motor to the desired location;
replace and securely tighten the four
bolts. See Figure 3.
Verify Electrical
Requirements
Vericationofthe electrical supply should be made to be certain the voltage, phase and frequency
match that of the pump motor. The proper operating voltage and other electrical information can
be found on the motor nameplate. These motors are designed to run on ±10% of the nameplate-
rated voltage. For multi-voltage motors, the motor should be internally connected to operate on
the voltage closest to the 10% rating, i.e., a 208 voltage motor wired per the 208 volt connection
diagram. Wiring connection diagrams can be found on plates attached to the motor.
If voltage variations are larger than ±10%, do not operate the pump.
Field Wiring
Wire sizes should be based on the current carrying properties of a conductor as required by the
latest edition of the National Electrical Code or local regulations.
Direct on line (D.O.L.) starting is approved due to the extremely fast run-up time of the motor and
the low moment of the inertia of pump and motor. If D.O.L. starting is not acceptable and reduced
starting current is required, an auto transformer or resistance starter should be used.
It is suggested that a fused disconnect be used for each pump where service and stand by pumps
are installed.
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Motor Protection
A. Single-Phase Motors:
With the exception of 7½ and 10 HP motors which require external protection, single phase LM/
LP pumps are equipped with multi-voltage, open-drip proof (O.D.P.) squirrel-cage induction motors
with built-in thermal protection.
B. Three-Phase Motors:
LM/LP Pumps with three-phase motors must use the proper size and type of motor-starter to en-
sure the motor is protected against damage from low voltage, phase failure, current imbalance and
overloads.Aproperlysizedstarterwithmanualresetandambient-compensatedextraquicktrip
in all three legs should be used. The overload should be sized and adjusted to trip at the full-load
current rating of the motor. If the motor is lightly loaded, the overload should be resized or adjusted
toalowervalue.Undernocircumstancesshouldtheoverloadsbesettoahighervaluethanthe
full load current shown on the motor nameplate. This will void the warranty.
Starting the Pump the First Time
After the pump has been installed, wired and the system lled, the following procedures must
be performed. Do not start the pump before priming or venting. Never operate the pump dry.
Priming
Electrical
Figure 4
pipe if one has been provided as suggested in the Installation Procedures section, Page 2. If no
othermeanstollthesuctionlinehasbeenprovided,removeoneofthegaugetappingplugsin
thepumpangesandpourwaterintotheholeusingafunnelorhosewithadapter.Allairinpump
and suction line must be purged prior to start-up.
Check the Direction of Rotation
1. Switch power off;
2. Checktomakesurethepumphasbeenlledandvented;
3. Removethecouplingguardandrotatethepumpshafttobecertainitturnsfreely.Replace
the coupling guard;
To prime the pump in a closed system
or an open system where the water
source is above the pump, close the
pump isolation valves and open the
airventscrew. See Figure 4. Gradually
open the suction side isolation valve
until a steady stream of airless water
runsoutofthe air venthole.Tightenthe
airventscrewandcompletely open the
isolation valves.
Inopensystems where the water level
is below the pump inlet, the suction
pipe and pump must be filled and
vented of air before starting the pump.
Closethedischargeisolationvalveand
open the air vent screw and suction
valve (if one is installed). Fill suction
linethroughthepluggedteeorcapped
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4. Verifythattheelectricalconnectionsareinaccordancewiththewiringdiagramonthemotor;
5. Switch the power on and observe the direction of rotation. WHEN VIEWED FROM THE MO-
TOR END, THE PUMP SHOULD ROTATE COUNTERCLOCKWISE;
6. Toreversethedirectionofrotation,rstswitchOFFthesupplypower;
7. On three-phase motors, interchange any two power leads at the load side of the starter. On
single-phase motors, see connection diagram on nameplate. Change wiring as required;
8. Switch on the power again and check for proper motor rotation.
Starting and Adjusting
Before starting the pump, please check that the:
1. Pump is primed;
2. Direction of rotation is counterclockwise when viewed from the motor end;
3. Allpipingconnectionsaretightandadequatelysupported;
4. Suction line isolation valve is completely opened, in a valve has been installed.
For initial starting:
1. The isolation valve in the discharge pipe should be closed and gradually opened after the
pump is turned on. Opening this valve to fast may result in some water hammering in the
discharge pipe. During operation, be sure this valve is completely open;
2. Checkandrecordthevoltageandamperageofthemotor.Adjustthemotoroverloadsifre-
quired;
3. Check and record operating pressures if pressure gauges have been installed;
4. Check all controls for proper operation. If pump is controlled by a pressure switch, check and
adjust the cut-in and cut-out pressure. If low-water level controls are used, be sure the low-
level switch is properly adjusted so the pump cannot run if the pump should break suction.
Operating Parameters
Grundfos LM/LP in-line centrifugal pumps installed in accordance with these instructions and sized
forcorrectperformancewilloperateefcientlyandprovideyearsofservice.Thepumpsareproduc-
tion lubricated and do not require any external lubrication or inspection. The motors will require
periodic lubrication as noted in the following Maintenance Section.
Undernocircumstancesshouldthepumpbeoperatedforanyprolongedperiodsoftimewithout
owthroughthepump.Thiscanresultinmotorandpumpdamageduetooverheating.Aproperly
sizedreliefvalveshouldbeinstalledtoallowsufcientwatertocirculatethroughthepumptoprovide
adequate cooling and lubrication of the pump bearing and seals.
Pump Cycling
Pump cycling should be checked to ensure the pump is not starting more than 20 times per hour
on ½ to 5 HP models; 15 times per hour on 7½ to 15 HP models; and 10 times per hour on 20 to
40HPmodels.Rapidcyclingisamajorcauseofprematuremotorfailureduetoincreasedheat
buildup in the motor. If necessary, adjust controls to reduce the frequency of starts and stops.
Starting the Pump the First Time
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Frequency of
Type of Service Greasing Approved Types of Grease
Seasonal(motorisidle Yearly ShellDoliumR Orcompatibleequivalenttypeofgrease
formorethan6months)  ChevronSRI#2
Intermittently Semiannually TexacoSRI#2. Mobilith SHC100 is
Continuous Quarterly Texaco“PremiumPB” required for 30 & 40 HP motors
For severe duty or extreme conditions, special motor frames or conguration, or any questions regarding
greasing procedures, contact the motor manufacturer.
Maintenance
Motor Lubrication
Electric motors are pre-lubricated at the factory and do not require additional lubrication at start-up.
Motorswithoutexternalgreasettingsdonotrequireadditionallubricationduringtherst15,000
hoursofoperation.Motorswithgreasettingsshouldonlybelubricatedwithapprovedtypesof
grease.Donotovergreasethebearings.Overgreasingwillscauseincreasedbearingheatandcan
result in bearing/motor failure. DO not mix petroleum grease and silicon grease in motor bearings.
Operating Parameters
Procedure
IfmotorisequippedwithAlemitetting,cleantipofttingandapplygreasegun.Use1to2full
strokesonmotorsinNEMA215frameorsmaller.Use2to3strokesonNEMA254throughNEMA
365frame.FormotorswithdrainplugsontheoppositesideofAlemitegreasettingatthepul-
ley end: remove grease drain plug and operate motor for 20 minutes before replacing drain plug.
Motor Replacement
If the motor is damaged due to bearing failure or electrical failure, the following instructions detail
howtoremovethemotorforreplacement.ItmustbeemphasizedthatmotorsusedonLM/LPpumps
arespecicallyselectedtoourrigidspecications.REPLACEMENT MOTORS MUST BE OF THE
SAME NEMAC FRAME SIZE, AND MUST BE EQUIPPED WITH THE SAME FRAME BEARINGS
AND RATED TO HAVE THE SAME SERVICE FACTOR. Failure to follow these recommendations
may result in premature motor failure.
Disassembly
1. Removethecouplingguards;
2. Usingthepropersizemetricallenwrench,loosenthefourcapscrewsinthecouplingand
spread coupling apart;
3. With the correct size wrench, loosen and remove the four bolts which hold the motor to the
pump end;
4. Lift the motor straight up until the shaft is free from the coupling.
Assembly
TABLE B: SHAFT ADJUSTING FORKS
Shaft Diameter Part No.
 0.630”(16mm) 480176
 0.866”(22mm) 480177
 1.300”(33mm) 480178
1. Thoroughlycleanthesurfacesofthemotorandpumpendmountinganges.Themotorand
shaft must be clean of all oil/grease and other contaminants where the coupling attaches. Set
the motor on the pump end, guiding the motor shaft into the coupling.
2. Place the terminal box in the desired position by rotating the motor.
3. Insert the motor mounting bolts, then diagonally and evenly tighten.
4. Removethecouplingadjustingforkboltedtothepumpmotorstool.Therequiredadjusting
fork is determined by shaft diameter for both the
LMandLPpumptypes.SeeTableBforthecorrect
adjusting fork.
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5. Using a large screwdriver, raise the pump
shaft by placing the tip of the screwdriver
under the coupling and carefully elevating
the coupling to its highest point. Note: The
shaft can only be raised approximately 0.20
inches (5mm). See Figure 5.
6. InserttheGrundfos adjustingforkunderneath
the coupling and lower the coupling until it
touches the adjusting fork. See Figure 6.
7. IT IS EXTREMELY IMPORTANT TO
TIGHTEN THE COUPLING SCREWS
CORRECTLY. The four allen head fasten-
ers should be tightened as follows. Tighten,
but not completely, the bottom fasteners on
one side of the coupling. Then tighten, but
notcompletely, the top and bottom fasteners
on the other side of the of the coupling so
that the gaps between the coupling halves
are equal. Repeat this procedure, tighten-
ing each side of the coupling successively
until the fasteners are torqued to the values
listed in Table C. Check to ensure the gaps
between the coupling halves are equal.
Loosen and adjust if necessary. See Figure
7.
Operating Parameters
TABLE C:
COUPLING BOLT TORQUE VALUES
Screw Size HP Ranges Torques
 M6x20 Upto5 10ft.-lbs.
M8 x 20 5 to 10 23 ft.-lbs.
M10 x 25 15 to 30 46 ft.-lbs.
8. Remove adjusting fork and be certain the
pump shaft can be rotated by hand. If the
shaft cannot be rotated or it binds, disas-
semble and check for misalignment.
9. Replaceadjustingforkandsecuretopump
housing.
10. Replacethetwocouplingguards.
Freeze Protection
If the pump is installed in an area where freezing
could occur, the pump and system should be
drained during freezing temperatures to avoid
damage. To drain the pump, close the isolation
valves, loosen the air vent screw and remove the
drain plug at the base of the pump. See Figure
8. Do not replace the drain plug or tighten the air
vent screw until the pump is to be used again.
Figure 5
Figure 6
Figure 7
Figure 8
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Regular Check-Ups
Atregularintervals,dependingontheconditionsandtimeofoperation,thefollowingchecks
should be made:
1. Pump meets required performance and is operating smoothly and quietly;
2. There are no leaks, particularly at the shaft seal;
3. The motor is not overheating;
4. Removeandcleanallstrainersorltersinthesystem;
5. Verifythetrippingofthemotoroverloadprotection;
6. Check the operation of all controls. Check until control cycling twice and adjust if necessary;
7. If the pump is not operated for unusually long periods, the unit should be maintained in ac-
cordance with these instructions. In addition, if the pump is not drained, the pump should be
manually rotated or run for short periods of time at monthly intervals.
If the pump fails to operate or there is a loss of performance, refer to the Troubleshooting
Section. Troubleshooting
WHEN WORKING WITH ELECTRICAL CIRCUITS, USE CAUTION TO AVOID
ELECTRICAL SHOCK. IT IS RECOMMENDED THAT RUBBER GLOVES AND BOOTS
BE WORN, AND METAL TERMINAL BOXES AND MOTORS ARE GROUNDED
BEFORE ANY WORK IS DONE.FOR YOUR PROTECTION, ALWAYS DISCONNECT
THE PUMP FROM ITS POWER SOURCE BEFORE HANDLING.
Preliminary Tests
Supply
Voltage
Operating Parameters
How to Measure
By means of a volt meter, which
has been set to the proper scale,
measure the voltage at the pump
terminal box or starter.
On three-phase units, measure
between the legs (phases).
What it Means
Whenthemotorisunderload,thevoltage
should be within ±10% of the nameplate
voltage. Larger voltage variation may
cause winding damage.
Large variations in the voltage indicate
a poor electrical supply and the pump
should not be operated until these varia-
tions have been corrected.
If the voltage constantly remains high or
low, the motor should be changed to cor-
rect the power supply.
Current
Measure How to Measure
By use of an ammeter, set on the
proper scale, measure the current
oneachpowerleadattheterminal
box or starter. See motor name-
plate for amp draw information.
Currentshouldbemeasuredwhen
the pump operating at constant
discharge when the motor is fully
loaded.
What it Means
Iftheampdrawexceedsthelisted service
factoramps(SFA)orifthecurrentunbal-
anceisgreaterthan5% between each leg
of three-phase units, check the following:
1. Burned contacts on motor starter;
2. Loose terminals in starter or terminal box or
possible wire defect. Check winding and in
sulation resistances;
3. Too high or low supply voltage;
4. Motor windings are shorted;
5. Pump is damaged causing a motor overload.
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Insulation
Resistance
Troubleshooting
Diagnosing Specic Problems
Problem Possible Cause Remedy
The pump does
not run Check for voltage at motor terminal box. If no voltage at motor, check feeder panel for
tripped circuits and reset circuit.
Turn off power and remove fuses. Check for
continuity with ohmmeter.  Replace blown
fuses or reset circuit breaker. If new fuses
blow or circuit breaker trips, the electrical in-
stallation,motorandwiresmustbechecked.
Check for voltage on line and load side of
starter. Replace burned heaters or reset.
Inspect starter for other damage. If heater
trips again, check the supply voltage and
starter holding coil.
Energizecontrolcircuitandcheckforvoltage
attheholdingcoil.If no voltage,checkcontrol
circuitfuses.Ifvoltage,check holding coil for
shorts.Replacebadcoil.
Check all safety and pressure switches
for operation. Inspect contacts in control
devices. Replace worn or defective parts
or controls.
Turn off power and disconnect wiring.
Measure the lead to lead resistances with
ohmmeter(RX-1).Measureleadtoground
valueswithohmmeter(RX-100K).Record
measured values. If an open or grounded
winding is found, remove motor and repair
or replace.
1. No power at motor.
2. Fuses are blown or
circuit breakers are
tripped.
3. Motorstarteroverloads
are burned or have
tripped out.
4. Starter does not ener-
gize.
5. Defective controls.
6. Motor is defective.
How to Measure
Turnoffpoweranddisconnectthesup-
ply power leads in the pump terminal
box.Usinganohmormegaohmmeter,
setthescaleselectortoRx100Kand
zero adjust the meter.
Measure and record the resistance
between each of the terminals and
ground.
What it Means
Motors of all HP, voltage, phase
and cycle duties have the same
value of insulation resistance.
Resistance values for new mo-
tors must exceed 1,000,000 ohm.
If they do not, motor should be
repaired or replaced.
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11
Troubleshooting
7. Defective capacitor.
(Single-phase motors)
8. Pump is bound.
Problem Possible Cause Remedy
The pump does
not run
The pump runs
but at reduced
capacity or does
not deliver water
1. Wrong rotation
2. Pump is not primed or
is airbound.
3. Strainers,checkorfoot
valves are
clogged.
4. Suction lift too large.
5. Suction and/or dis-
charge piping leaks.
6. Pump worn.
Check wiring for proper connections. Cor-
rect wiring.
Turn pump off, close isolation valve(s), re-
moveprimingplug.Checkuidlevel.Rell
the pump, replace plug and start the pump.
Longsuctionlinesmustbelledbeforestart-
ing the pump.
Remove strainer, screen or valve and in-
spect.Cleanandreplace.Reprimepump.
Install compound pressure gauge at the
suction side of the pump. Start pump and
comparereadingtoperformancedata.Re-
duce suction lift by lowering pump, increase
suction line size or removing high friction
loss devices.
Pumprunsbackwardswhenturnedoff.Air
insuctionpipe.Suctionpipe,valvesandt-
tingsmustbeairtight.Repairanyleaksand
retightenallloosettings.
Installpressuregauge,startpump,gradually
close the discharge valve and read pressure
at shutoff. Convert measured pressure
(in PSI) to head (in feet): (Measured PSI
x 2.31 ft./PSI = _____ ft.).   Refer to the
specific pump curve for shutoff head for
that pump model. If head is close to curve,
pumpisprobablyOK.Ifnot,removepump
and inspect.
Turn off power and discharge capacitor.
Checkwithohmmeter(RX-100K).When
themeterisconnectedtothecapacitor, the
needle should jump towards 0 ohms and
slowlydriftbacktoinnity().Replace
if defective.
Turn off power and manually rotate pump
shaft. If shaft does not rotate easily, check
coupling setting and adjust as necessary.
If shaft rotation is still tight, remove pump
and inspect. Disassemble and repair.
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12
Troubleshooting
Problem Possible Cause Remedy
The pump runs
but at reduced
capacity or does
not deliver water
Pump cycles too
much
7. Pump impeller or
guide vane is
clogged.
8. Incorrect drain plug
installed.
1. Pressureswitchisnot
properlyadjustedoris
defective.
2. Level control is not
properly set or is de-
fective.
3. Insufcientaircharg-
ing or leaking tank or
piping.
4. Tank is too small.
5. Pump is oversized.
Disassemble and inspect pump passage-
ways.Removeanyforeignmaterialsfound.
If the proper drain plug is replaced with a
standardplug,waterwillrecirculate internally.
Replacewithproperplug.
Checkpressuresettingonswitchandopera-
tion. Check voltage across closed contacts.
Readjustswitchorreplaceifdefective.
Checksettingandoperation.Readjustset-
ting (refer to level control manufacturer’s
data).Replaceifdefective.
Pump air into tank or diaphragm chamber.
Check diaphragm for leak. Check tank and
piping for leaks with soap and water solu-
tion.Checkairtowatervolume.Repairas
necessary.
Checktanksizeandairvolumeintank. Tank
volume should be approximately 10 gallons
for each gpm of pump capacity. The normal
air volume is 2/3 of the total tank volume at
thepumpcut-inpressure.Replacetankwith
one of correct size.
Install pressure gauges on or near pump
suction and discharge ports. Start and run
pumpundernormalconditions,recordgauge
readings. ConvertPSItofeet(MeasuredPSI
x2.31ft./PSI=_______ft.)Refertothespe-
cicpumpcurveforthatmodel,ensurethat
totalheadissufcienttolimitpumpdelivery
withinitsdesignowrange.Throttlepump
dischargeowifnecessary.
L-LM-TL-001_LM,LP I&O_0611.indd 12 6/8/2011 8:50:38 AM

13
Troubleshooting
Problem Possible Cause Remedy
Fuses blow or
circuit breakers
or overload
relays trip
Check voltage at starter panel and motor. If
voltagevariesmorethan±10%,contactpower
company. Check wire sizing.
Cyclepumpandmeasureamperage. Increase
heater size or adjust trip setting to a maximum
of motor nameplate (full load) current.
Check current draw on each lead to the mo-
tor. Must be within ±5%. If not, check motor
andwiring.Rotatingallleadsmayeliminate
this problem.
Turnoffpoweranddisconnectwiring. Measure
the lead-to-lead resistance with an ohmmeter
(RX-1).Measurelead-to-groundvalueswith
anohmmeter(RX-100K)oramegaohmmeter.
Recordvalues.Ifanopenorgroundedwind-
ing is found, remove the motor, repair and/or
replace.
Checkproperwiringand looseterminals. Tight-
enlooseterminals.Replacedamagedwire.
Turnoffpower and manuallyrotatepumpshaft.
If shaft does not rotate easily, check coupling
setting and adjust as necessary. If shaft rota-
tion is still tight, remove pump and inspect.
Disassemble and repair.
Turnoffpower and discharge capacitor. Check
withohmmeter(RX-100K).Whenthemeteris
connected to the capacitor, the needle should
jump towards 0 ohms and slowly drift back to
innity().Replaceifdefective.
Use a thermometer to check the ambient
temperature near the overloads and motor.
Recordthesevalues.Ifambienttemperature
at motor is lower than at overloads, especially
wheretemperatureatoverloadsis above104°F
(40°C), ambient-compensated heaters should
replace standard heaters.
1. Low voltage.
2. Motor overloads are
set too low.
3. Three-phasecurrentis
imbalanced.
4. Motor is shorted or
grounded.
5. Wiring or connections
are faulty.
6. Pump is bound.
7. Defective capacitor
(single-phase
motors).
8. Motor overloads at
higher ambient tem-
perature than motor.
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14
Notes
L-LM-TL-001_LM,LP I&O_0611.indd 14 6/8/2011 8:50:38 AM

15
Notes
L-LM-TL-001_LM,LP I&O_0611.indd 15 6/8/2011 8:50:38 AM

16
LIMITED WARRANTY
Productsmanufacturedby(GRUNDFOS)GRUNDFOSPUMPSCORPORATION
are warranted to the original user only to be free of defects in material and work-
manship for a period of 18 months from date of installation, but not more than 24
monthsfromdateofmanufacture.GRUNDFOS’liabilityunderthiswarrantyshall
belimitedtorepairingorreplacingatGRUNDFOS’option,withoutcharge,F.O.B.
GRUNDFOS’factoryorauthorizedservicestation,anyproductofGRUNDFOS’
manufacture.GRUNDFOS will notbe liablefor anycosts of removal, installa-
tion, transportation, or any other charges which may arise in connection with a
warrantyclaim.ProductswhicharesoldbutnotmanufacturedbyGRUNDFOS
are subject to the warranty provided by the manufacturer of said products and
notbyGRUNDFOS’warranty.GRUNDFOSwillnotbeliablefordamageorwear
to products caused by abnormal operating conditions, accident, abuse, misuse,
unauthorized alteration or repair, or if the product was not installed in accordance
withGRUNDFOS’printedinstallationandoperatinginstructions.
To obtain service under this warranty, the defective product must be returned to
thedistributorordealerofGRUNDFOS’productsfromwhichitwaspurchased
together with proof of purchase and installation date, failure date, and supporting
installationdata.Unlessotherwiseprovided,thedistributorordealerwillcontact
GRUNDFOS or an authorized service station for instructions.Any defective
producttobereturnedtoGRUNDFOSoraservicestationmustbesentfreight
prepaid;documentationsupportingthewarrantyclaimand/oraReturnMaterial
Authorizationmustbeincludedifsoinstructed.
GRUNDFOS WILL NOT BE LIABLE FORANYINCIDENTALOR CONSEQUEN-
TIAL DAMAGES, LOSSES, OR EXPENSES ARISING FROM INSTALLATION,
USE,ORANY OTHER CAUSES. THEREARE NOEXPRESSORIMPLIEDWAR-
RANTIES, INCLUDINGMERCHANTABILITY OR FITNESS FORAPARTICULAR
PURPOSE, WHICH EXTEND BEYOND THOSE WARRANTIES DESCRIBED
OR REFERRED TO ABOVE.
Some jurisdictions do not allow the exclusion or limitation of incidental or con-
sequential damages and some jurisdictions do not allow limitations on how long
implied warranties may last. Therefore, the above limitations or exclusions may
notapplytoyou.Thiswarrantygivesyouspeciclegalrightsandyoumayalso
have other rights which vary from jurisdiction to jurisdiction.
L-LM-TL-001 Rev.6/11
Repl.12/99
PRINTEDINU.S.A.
L-LM-TL-001_LM,LP I&O_0611.indd 16 6/8/2011 8:50:38 AM