COOK QMX Series User manual

1QMX IO&M B51092-005
®
QMX
Mixed Flow Inline
INSTALLATION, OPERATION AND MAINTENANCE MANUAL
Receiving and Inspection
Carefully inspect the fan and accessories for any damage
and shortage immediately upon receipt of the fan.
• Turn the wheel by hand to ensure it turns freely and does not
bind
• Inspect inlet vane dampers (if supplied) for free operation of all
moving parts
• Record on the Delivery Receipt any visible sign of damage
Handling
Lift the fan by lifting lugs.
NOTICE! Never lift by the shaft, motor or housing.
QMX
Rotating Parts & Electrical Shock Hazard:
Fans should be installed and serviced by qualied personnel
only.
Disconnect electric power before working on unit (prior to re-
moval of guards or entry into access doors).
Follow proper lockout/tagout procedures to ensure the unit
cannot be energized while being installed or serviced.
A disconnect switch should be placed near the fan in order
that the power can be swiftly cut o󰀨, in case of an emergency
and in order that maintenance personnel are provided com-
plete control of the power source.
Grounding is required. All eld-installed wiring must be com-
pleted by qualied personnel. All eld installed wiring must
comply with National Electric Code (NFPA 70) and all applica-
ble local codes. Ensure the power supply (voltage, frequency
and current carrying capacity of wires) is in accordance with
the motor nameplate.
Fans and blowers create pressure at the discharge and vac-
uum at the inlet. This may cause objects to get pulled into the
unit and objects to be propelled rapidly from the discharge.
The discharge should always be directed in a safe direction
and inlets should not be left unguarded. Any object pulled into
the inlet will become a projectile capable of causing serious
injury or death.
When air is allowed to move through a non-powered fan, the
impeller can rotate, which is referred to as windmilling. Wind-
milling will cause hazardous conditions due to unexpected ro-
tation of components. Impellers should be blocked in posi-
tion or air passages blocked to prevent draft when working
on fans.
Friction and power loss inside rotating components will cause
them to be a potential burn hazard. All components should be
approached with caution and/or allowed to cool before con-
tacting them for maintenance.
Under certain lighting conditions, rotating components may
appear stationary. Components should be veried to be sta-
tionary in a safe manner, before they come into contact with
personnel, tools or clothing.
Failure to follow these instructions could result in death or se-
rious injury.
The attachment of roof mounted fans to the roof curb as well
as the attachment of roof curbs to the building structure must
exceed the structural requirements based on the environmen-
tal loading derived from the applicable building code for the
site. The local code o󰀩cial may require variations from the
recognized code based on local data. The licensed engineer
of record will be responsible for prescribing the correct attach-
ment based on construction materials, code requirements and
environmental e󰀨ects specic to the installation.
This publication contains the installation, operation and
maintenance instructions for standard units of the QMX:
Mixed Flow Inline.
Carefully read this publication and any
supplemental documents prior to any
installation or maintenance procedure.
Cook website provides additional information describing
the equipment, fan performance, available accessories and
specication data.
For additional safety information, refer to AMCA Publication
410- 9 6, Safety Practices for Users and Installers of Industrial
and Commercial Fans.
All of the publications listed above can be obtained from:
• lorencook.com
• [email protected]
• 417-869-6474 ext. 166
For information and instructions on special equipment,
contact Loren Cook Company at 417-869-6474.
• QMX
• QMXHPD
• QMXHP
• QMXE
• QMXS
• QMXHPE
• QMXHPS
• QMXU
• QMXHPU
• QMXLE
• QMXHPLE
• QMXD
• QMXXP
• QMXVP
• QMXHPVP

2QMX IO&M B51092-005
NOTICE! Although a certain amount of vibration is
inherent in operating fans, extreme vibration is a
serious problem that may cause structural and me-
chanical failure.
Isolation Installation
To help prevent vibration and noise from being transferred
to the building, isolators are recommended.
Floor Mounted Spring Isolators
1. Mount fan on isolation base or rails (if supplied).
2. Elevate fan (or isolation base) to operating height and
insert blocks to hold in position.
3. Position isolators under the fan and vertically align by
inserting leveling bolt through mounting holes in the fan or
the base. The isolator must be installed on a level surface.
4. Adjust the isolators by turning the leveling nut
counterclockwise several turns at a time alternately on
each isolator until the fan weight is transferred onto the
isolators and the fan raises uniformly o󰀨 the blocks. Then
remove the blocks.
5. Turn lock nut onto leveling bolt and secure rmly in place
against the top of the mounting ange or frame.
6. Secure isolators to mounting surface.
Spring Isolator Rubber-in-Shear Isolator
Figure 1 - Floor Mount Isolators
Floor Mounted Rubber-In-Shear (RIS) Isolators
1. Mount fan on isolation base or rails (if supplied).
2. Elevate fan to provide room to insert isolators between the
fan and foundation and block in position.
3. Position isolators under fan and secure bolts.
4. Remove blocks and allow fan to rest on oor. Isolators
must be installed on a level surface (leveling should not
be required).
5. Secure isolators to mounting surface.
Ceiling Mounted Spring and Rubber-in-Shear (RIS)
Isolators
1. Elevate fan to operating height and brace.
2. Attach threaded rod to overhead support structure directly
above each mounting hole. Rod should extend to within a
few feet of fan.
3. Attach isolator to end of threaded rod using a nut on each
side of isolator bracket.
4. Insert another section of threaded rod through the fan
mounting hole and isolator.
5. Attach two nuts to threaded rod in isolator.
6. Place adjusting nut and locking nut on threaded rod near
fan mounting bracket.
7. Alternately rotate adjusting nut at each mounting location
until the fan weight is uniformly transferred to the isolators.
Remove bracing.
Ceiling Mounted Spring Isolator Rubber-in-Shear Ceiling Isolator
Figure 2 - Ceiling Mount Isolators
Storage
If the fan is stored for any length of time prior to installation,
completely ll the bearings with grease or moisture-inhibiting oil
(refer to Lubrication, page 6). Store the fan in its original crate
and protect it from dust, debris and weather.
• Cover the inlet, outlet and belt tunnel opening to prevent the
accumulation of dirt and moisture in the housing
• Periodically rotate the wheel and operate inlet vane damp-
ers (if supplied) to keep a coating of grease on all internal
bearing parts
• Periodically inspect the unit to prevent damaging conditions
Installation
QMX, QMX-HP and QMX-XP can be mounted horizontally
or vertically to a oor or a ceiling in various motor positions
and discharges.(See Mounting Detail) QMXU, QMXHPU,
QMXE, QMXHPE, QMXS and QMXHPS are all designed to
be roof mounted on typical roof curbs. The QMX-LE or QMX-
VP units, however, should not be mounted on sheet metal roof
curbs, but supported by integral members of the roof structure,
designed and constructed by others per local requirements
and environments.
Most motors are shipped mounted on the fans with belts
and drives installed. However, extremely heavy motors are
shipped separately, and some motors are shipped separately
due to height limitations. These motors and drives will require
eld installation.
Mounting Detail
Recommended
Mounting Base
Recommended
Mounting Base
Recommended
Mounting Rails
Recommended
Mounting Rails
Recommended
Mounting Rails
Recommended
Mounting Rails
G
G
A
A
C
C
B
D
E
F
H

3QMX IO&M B51092-005
Wheel-to-Inlet Clearance
The correct wheel-to-inlet clearance is critical to proper fan
performance. This clearance should be veried before initial
start-up since rough handling during shipment could cause a
shift in fan components. Refer to wheel/inlet drawing below for
correct overlap.
Adjust the overlap by loosening the wheel hub and moving
the wheel along the shaft to obtain the correct value. Trim
balance as necessary following procedure (0.0785 in/sec
max).
A uniform radial gap (space between the edge of the cone
and the edge of the inlet) is obtained by loosening the inlet
cone bolts and repositioning the inlet cone.
Wheel/Inlet Overlap
SEE DETAIL A
DETAIL A
OVERLAP
RADIAL
GAP
Belt and Pulley Installation
Belt tension is determined by the sound the belts make when
the fan is rst started. The belts will produce a loud squeal
which dissipates after the fan is operating at full capacity. If
belt tension is too tight or too loose, lost e󰀩ciency and damage
can occur.
Do not change the pulley pitch diameter to change
tension. This will result in a di󰀨erent fan speed.
1. Loosen motor plate adjustment bolts and move motor
plate in order that the belts can easily slip into the grooves
on the pulleys. Never pry, roll or force the belts over the
rim of the pulley.
2. Adjust the motor plate until proper tension is reached. For
proper tension, a deection of approximately 1/4” per foot
of center distance should be obtained by rmly pressing
the belt. Refer to Figure 3.
3. Lock the motor plate adjustment nuts in place.
4. Ensure pulleys are properly aligned. Refer to Figure 4.
Duct and Damper Installation
E󰀩cient fan performance relies on the proper installation of inlet
and discharge ducts as well as dampers. Be sure your fan conforms
to the following guidelines and allows three duct diameter of straight
duct before placing an elbow or damper. Clearance is also required
on the inlet and outlet for maintenance such as pulley or bearing
replacement.
Non-Ducted Inlet Clearance
If your fan has an open inlet (no duct work), the fan must
be placed one e󰀨ective wheel diameter away from walls and
bulkheads.
MIN
1 DIA
Non-ducted Inlet Clearance
Free Discharge
Avoid a free discharge into the plenum. This will result in lost
e󰀩ciency because it doesn’t allow for a static regain.
Correct
Incorrect
Free Discharge
Inlet Duct Turns
For ducted inlets, allow at least three e󰀨ective wheel
diameters between duct turns or elbows and the fan inlet.
Correct
Incorrect
MIN
3 DIA
Inlet Duct Turns
Discharge Duct Turns
Where possible, allow three duct diameters between duct
turns or elbows and the fan outlet.
Correct
Incorrect
MIN
3 DIA
Discharge Duct Turns
Size Overlap
(inches)
90 5/32
120 3/16
135 3/16
150 7/32
165 7/32
180 7/32
202 1/4
225 9/32
245 5/16
270 5/16
300 3/8
330 13/32
365 7/16
402 1/2
445 17/32
490 19/32
540 21/32
600 3/4
1 foot
1/4 inch
Figure 3

4QMX IO&M B51092-005
Wiring
Line reactors may be required to reduce over-voltage spikes
in the motors. The motor manufacturer should be consulted
for recommended line impedance and usage of line reactors
or lters if the lead length between the VFD and the motor
exceeds 10 ft (3m).
Fan
It is the responsibility of the installing body to perform coast-
down tests and identify any resonant frequencies after the
equipment is fully installed. These resonant frequencies are
to be removed from the operating range of the fan by using
the “skip frequency” function in the VFD programming. Failure
to remove resonant frequencies from the operating range will
decrease the operating life of the fan and void the warranty.
Wiring Diagrams
Single Speed, Single Phase Motor
T-
1
T-
4
Ground B
L2
L1
Ground A
Line
When ground is required, attach to ground A or B with No. 6
thread forming screw. To reverse, interchange T-1 and T-4.
2 Speed, 2 Winding, Single Phase Motor
Ground A
Ground B
T-
1
T-
4
Low Speed
High Speed
L1
L2
Line
When ground is required, attach to ground A or B with No.
6 thread forming screw. To reverse, interchange T-1 and T-4
leads.
Single Speed, Single Phase, Dual Voltage
Ground B
J-10
T-5
Ground A
Link A
Link B
Low Voltage
Line
L2
L1
Ground A
Link A
and B
L1
L2
Line
Ground B
T-5
J-10
When ground is required, attach to ground A or B with No. 6
thread forming screw. To reverse, interchange T-5 and J-10
leads.
Pulley Alignment
Pulley alignment is adjusted by loosening the motor pulley
setscrew and by moving the motor pulley on the motor shaft.
Tolerance
Center
Distance
Max.
Gap
Up through 12” 1/16”
12” through 48” 1/8”
Over 48” 1/4”
OFFSET ANGULAR OFFSET/ANGULAR
A
W
X
Y
Z
B
CENTER
DISTANCE
(CD)
GAP GAP
Figure 4 indicates where to measure the allowable gap
for the drive alignment tolerance. All
contact points (indicated by WXYZ) are
to have a gap less than the tolerance
shown in the table. When the pulleys
are not the same width, the allowable
gap must be adjusted by half of the
di󰀨erence in width. Figure 5 illustrates
using a carpenter’s square to adjust
the position of the motor pulley until
the belt is parallel to the longer leg of
the square.
Wiring Installation
NOTICE! Lock o all power sources before unit is
wired to power source.
Leave enough slack in the wiring to allow for motor movement
when adjusting belt tension. Some fractional motors have to
be removed in order to make the connection with the terminal
box at the end of the motor. To remove motor, remove bolts
securing motor base to power assembly. Do not remove motor
mounting bolts.
NOTICE! Follow the wiring diagram in the discon-
nect switch and the wiring diagram provided with
the motor. Correctly label the circuit on the main
power box and always identify a closed switch to
promote safety (i.e., red tape over a closed switch).
Use of Variable Frequency Drives
Motors
Motors that are to be operated using a Variable Frequency
Drive (VFD) must be VFD compatible. At a minimum, this
must be a Premium E󰀩ciency motor with Class F insulation.
Motors that are not supplied by Loren Cook Company should
have the recommendation of the motor manufacturer for use
with a VFD.
Grounding
The fan frame, motor and VFD must be connected to a
common earth ground to prevent transient voltages from
damaging rotating elements.
Figure 4

5QMX IO&M B51092-005
3 Phase, 9 Lead Motor
456
1
7
2
8
3
9
L1L2L3
456
789
12 3
L1L2L3
Low Voltage
208/230 Volts
High Voltage
460 Volts
3 Phase, 9 Lead Motor
Y-Connection
7
1
6789
456
12 3
Low Voltage
208/230 V
olts
High V
oltage
460 Volts
8
2
4
9
3
5
L1L3
L
2
L1L3
L2
3 Phase, 9 Lead Motor
Delta-Connection
To reverse, interchange any two line leads.
2 Speed, 1 Winding, 3 Phase Motor
Motor
1
2
3
4
5
6
Together
High Speed
Line
L1
L2
L
3
1
2
3
4
5
6
Open
Low Speed
Line
L1
L2
L3
Motor
To reverse, interchange any two line leads. Motors require
magnetic control.
2 Speed, 2 Winding, 3 Phase
L1
T
1
T
2
T
3
Low Speed
Low Speed
Low Speed
High Speed
High Speed
High Speed
Motor
T
13
T
12
T
11
L2Line
L3
To reverse:
High Speed - interchange leads T11 and T12.
Low Speed - interchange leads T1and T2.
Both Speeds - interchange any two line leads.
Typical Wiring Path for Roof Mounted Units
For sizes 135–600, route conduit under motor cover
between the motor support rails and out to enclosure as
shown in Figure 1 below.
Weather Cover
Liquidtite
Size 135-600, Run
Liquidtite Between
We
ather Cover and Unit
Figure 1
For sizes 90–120, route conduit through holes in the sides of
the motor support saddle as shown in Figure 2 below.
Enclosure May Be Located
in Either Corner
(Liquidtite Not Shown)
90-120, Run
Liquidtite
Through
Holes in Saddle
Figure 2
Wheel Rotation
Test the fan to ensure the rotation of the wheel is the same
as indicated by the arrow marked Rotation.
115 and 230 Single Phase Motors
Fan wheel rotation is set correctly at the factory. Changing
the rotation of this type of motor should only be attempted by
a qualied electrician.
208, 230 and 460 3 Phase Motors
These motors are electrically reversible by switching two
of the supply leads. For this reason, the rotation of the fan
cannot be restricted to one direction at the factory. See Wiring
Diagrams for specic information on reversing wheel direction.
NOTICE! Do not allow the fan to run in the wrong
direction. This will overheat the motor and cause
serious damage. For 3-phase motors, if the fan is
running in the wrong direction, check the control
switch. It is possible to interchange two leads at this
location so that the fan is operating in the correct
direction.
QMX
QMX-XP Correct Airflow
Direction
QMX-HP
NOTICE! Do not allow the fan airow to go in the
wrong direction.

6QMX IO&M B51092-005
Maintenance
Establish a schedule for inspecting all parts of the fan. The
frequency of inspection depends on the operating conditions
and location of the fan.
Inspect fans exhausting corrosive or contaminated air within
the rst month of operation. Fans exhausting contaminated air
(airborne abrasives) should be inspected every three months.
Regular inspections are recommended for fans exhausting
non-contaminated air.
It is recommended the following inspections be con-
ducted twice per year:
• Inspect bolts and setscrews for tightness. Tighten as
necessary
• Inspect belt wear and alignment. Replace worn belts with
new belts and adjust alignment as needed. Refer to Belt and
Pulley Installation, page 3
• Bearings should be inspected as recommended in the Con-
ditions Chart
• Inspect variable inlet vanes (if supplied) for freedom of op-
eration and excessive wear. The vane position should agree
with the position of the control arm. As the variable inlet
vanes close, the entering air should spin in the same direc-
tion as the wheel
• Inspect springs and rubber isolators for deterioration and
replace as needed
• Inspect for cleanliness. Clean exterior surfaces only. Re-
moving dust and grease on motor housing assures proper
motor cooling. Removing dirt from the wheel and housing
prevents imbalance and damage
Lubrication
Fan Bearings
QMX bearings are lubricated through a grease tting on the
exterior of the fan housing and should be lubricated by the
schedule, Conditions Chart.
For best results, lubricate the bearing while the fan is in
operation. Pump grease in slowly until a slight bead forms
around the bearing seals. Excessive grease can burst seals
thus reducing bearing life.
Lubrication Conditions Chart
Fan
Class Fan Status Shaft Size Maximum Interval (operation hrs)
QMX
Normal Conditions
(clean, dry & smooth)
>1-1/2” 7500
<1-1/2” 2000
Extreme Conditions
(dirty/wet/rough)
>1-1/2” 1500
<1-1/2” 400
QMXHP
Normal Conditions
(clean, dry & smooth)
>2” 5000
<2” 1000
Extreme Conditions
(dirty/wet/rough)
>2” 1000
<2” 200
QMXXP
Normal Conditions
(clean, dry & smooth)
>4” 2000
<4” 1000
Extreme Conditions
(dirty/wet/rough)
>4” 400
<4” 200
In the event the bearing cannot be seen, use no more than
three injections with a hand-operated grease gun.
Before lubricating, the grease nipple and immediate vicinity
should be thoroughly cleaned without the use of high pressure
equipment. The grease should be supplied slowly as the
bearing rotates until fresh grease slips past the seal. Excessive
pressure should be avoided to prevent seal damage.
Final Installation Steps
1. Inspect fasteners and setscrews, particularly fan
mounting and bearing fasteners then tighten according to
Recommended Torque for Setscrews/Bolts.
2. Inspect for correct voltage with a voltmeter.
3. Ensure all accessories are installed.
Operation
Pre-Start Checks
1. Lock out all the primary and secondary power sources.
2. Ensure fasteners and setscrews, particularly those used
for mounting the fan, are tightened.
3. Inspect belt tension and pulley alignment.
4. Inspect motor wiring.
5. Ensure belt touches only the pulley.
6. Ensure fan and ductwork are clean and free of debris.
7. Inspect wheel-to-inlet clearance. The correct wheel-to-
inlet clearance is critical to proper fan performance.
8. Close and secure all access doors.
9. Restore power to fan.
Start-Up
Turn on the fan. In variable speed units, set fan to its lowest
speed and inspect for the following:
• Direction of rotation
• Excessive vibration
• Unusual noise
• Bearing noise
• Improper belt alignment or tension (listen for squealing)
• Improper motor amperage or voltage
NOTICE! If a problem is discovered, immediately
shut o the fan. Lock out all electrical power
and check for the cause of the trouble. Refer to
Troubleshooting.
Inspection
Inspection of the fan should be conducted at the rst 30
minute, 8 hour and 24 hour intervals of satisfactory opera-
tion. During the inspections, stop the fan and inspect as per
the Conditions Chart.
30 Minute Interval
Inspect bolts, setscrews and motor mounting bolts. Adjust
and tighten as necessary.
8 Hour Interval
Inspect belt alignment and tension. Adjust and tighten as
necessary.
24 Hour Interval
Inspect belt tension. Adjust and tighten as necessary.
Recommended Torque for Setscrews/Bolts (IN-LB)
Setscrews Hold Down Bolts
Size
Key Hex
Across
Flats
Recommended
Torque Size Recommended
Torque
Min. Max.
#8 5/64” 15 21 3/8”-16 324
#10 3/32” 27 33 1/2”-13 780
1/4 1/8” 70 80 5/ 8”-11 1440
5/16 5/32” 140 160 3/4”-10 2400
3/8 3/16” 250 290 7/8”-9 1920
7/16 7/32” 355 405 1”-8 2700
1/2 1/4” 560 640 1-1/8”-7 4200
5/8 5/16” 1120 1280 1-1/4”-7 6000
3/4 3/8” 1680 1920 - -
7/8 1/2” 4200 4800 - -
19/16” 5600 6400 - -

7QMX IO&M B51092-005
Exceptions to the greasing interval chart:
• Periodic Applications (any break of one week or more):
It is recommended that full lubrication be performed prior to
each break in operation
• Higher Temperature: It is recommended to halve the inter-
vals for every 30°F increase in operating temperature above
120°F not to exceed 230°F for standard bearings; high tem-
perature bearings (optional) can operate up to 400°F
• Vertical Shaft: It is recommended that the intervals should
be halved
Loren Cook Company uses petroleum lubricant in a lithium
base. Other types of grease should not be used unless the
bearings and lines have been ushed clean. If another type of
grease is used, it should be a lithium-based grease conforming
to NLGI grade 2 consistency.
A NLGI grade 2 grease is a light viscosity, low-torque, rust-
inhibiting lubricant that is water resistant. Its temperature
range is from -30°F to +200°F and capable of intermittent
highs of +250°F.
Motor Bearings
Motors are provided with prelubricated bearings. Any
lubrication instructions shown on the motor nameplate
supersede instructions below.
Motor bearings without provisions for relubrication will
operate up to 10 years under normal conditions with no
maintenance. In severe applications, high temperatures or
excessive contaminates, it is advisable to have the maintenance
department disassemble and lubricate the bearings after three
years of operation to prevent interruption of service.
For motors with provisions for relubrication, follow intervals
of the table below.
Relubrication Intervals
Service
Conditions
NEMA Frame Size
Up to and
Including 184T 213T-365T 404T and Larger
1800
RPM
and
Less
Over
1800
RPM
1800
RPM
and
Less
Over
1800
RPM
1800 RPM
and Less
Over
1800
RPM
Standard 3 yrs. 6 months 2 yrs. 6 months 1 yr. 3 months
Severe 1 yr. 3 months 1 yr. 3 months 6 months 1 month
Motors are provided with a polyurea mineral oil NGLI #2
grease. All additions to the motor bearings are to be with
a compatible grease such as Exxon Mobil Polyrex EM and
Chevron SRI.
The above intervals should be reduced to half for vertical
shaft installations.
Motor Services
Should the motor prove defective within a one-year period,
contact your local Loren Cook representative or your nearest
authorized electric motor service representative.
Changing Shaft Speed
All belt driven fans with motors up to and including 5HP are
equipped with variable pitch pulleys. To change the fan speed,
perform the following:
1. Loosen setscrew on driver (motor) pulley and remove key,
if equipped.
2. Turn the pulley rim to open or close the groove facing. If
the pulley has multiple grooves, all must be adjusted to
the same width.
3. After adjustment, inspect for proper belt tension.
Maximum RPM
Size QMX QMXHP QMXXP
Level 1 Level 2 Level 1 Level 2 Level 2 Level 3
90 -4000 -4000 - -
120 -3707 -4000 - -
135 -3295 -3876 - -
150 -2907 -3510 2920 3940
165 1975 2633 2368 3191 2654 3582
180 1811 2420 2171 2884 2433 3231
202 1610 2152 1935 2600 2168 2919
225 1449 1937 1737 2340 1947 2626
245 1330 1774 1595 2097 1767 2361
270 116 6 1623 1386 1819 1603 2134
300 1000 1465 1248 1679 1426 1921
330 856 1332 1134 1527 1296 1791
365 801 1204 1026 1381 1172 1604
402 709 1080 931 1252 1064 1458
445 612 988 841 1132 961 1312
490 602 897 759 1028 871 1202
540 523 813 693 912 792 1069
600 459 732 624 840 703 959
Speed Reduction
Open the pulley in order that the belt rides deeper in the
groove (smaller pitch diameter).
Speed Increase
Close the pulley in order that the belt rides higher in the
groove (larger pitch diameter). Ensure that the RPM limits of
the fan and the horsepower limits of the motor are maintained.
Pulley and Belt Replacement
1. Loosen and remove belts by adjusting motor mounting
plate.
2. Remove pulleys from their respective shafts.
3. Clean the motor and fan shafts.
4. Clean bores of pulleys and coat bores with heavy oil.
5. Remove grease, rust or burrs from pulleys and shafts.
6. Remove burrs from shaft by sanding.
7. Place fan pulley on fan shaft and motor pulley on motor
shaft. Damage to pulleys can occur when excessive force
is used in placing the pulleys on their respective shafts.
8. Tighten in place.
9. Install belts on pulleys and align as described in Belt and
Pulley Installation, page 3.
Bearing Replacement
The fan bearings are pillow block ball bearings.
1. Loosen and remove belts by adjusting motor mounting
plate.
2. Remove the bearing cover by removing the bolts around
the perimeter of the bearing cover. Do not remove fan
sheave yet.
3. Remove inlet cone by removing attaching bolts/nuts
around perimeter of the inlet plate.
4. Remove wheel by loosening setscrews and sliding o󰀨
shaft.
5. Record the location of the fan sheave from end of shaft,
and remove the sheave.
6. Record the distance from the bearing to the end of the
shaft.
7. Loosen setscrews on bearings and remove shaft.
8. Remove bearings from bearing base and replace with
new ones, noting the exact location of each; do not fully
tighten base bolts.
9. Slide shaft through bearings until shaft protrudes the
same amount as measured above. Tapping the inner race
of each bearing with a soft driver may be required. Do not
hammer the end of the shaft or the bearing housing.
10. Return setscrews to the same location as marked above
and tighten one setscrew on each bearing to half its
specied torque.

8QMX IO&M B51092-005
11. Rotate shaft to allow bearings to align themselves.
12. Replace wheel but do not tighten yet.
13. Replace inlet cone. Wheel may need to be moved to allow
proper alignment. Care should be taken to insure that inlet
cone is centered inside wheel before and after tightening
attaching bolts.
14. Slide wheel on shaft to achieve proper wheel/inlet overlap
and tighten wheel set screws. Refer to Wheel-to-Inlet
Clearance, page 3.
15. Tighten hold-down bolts to proper torque.
16. Turn the shaft by hand. Resistance should be the same as
it was before hold-down bolts were fully tightened.
17. Tighten all bearing setscrews to full specied torque.
18. Replace the sheave, align with motor sheave and adjust
the belt tension.
19. Test run fan and retighten all setscrews and bolts and trim
balance as necessary. (0.0785 in/sec max).
20. Replace discharge cover.
Wheel Replacement (Belt Drive)
The wheel has a pre-machined shoulder in the hub for the
use of most two and three jaw mechanical pullers.
1. Align center of the puller with the center of the shaft.
2. Ensure all setscrews in the hub, normally two, are fully
removed.
3. Slowly remove wheel from the shaft.
Troubleshooting
Problem and Potential Cause
Low Capacity or Pressure:
• Incorrect direction of rotation. Make sure the fan rotates
in same direction as the arrows on the motor or belt drive
assembly
• Poor fan inlet conditions. There should be a straight clear
duct at the inlet or outlet
• Improper wheel alignment
• Fan backwards. Refer to airow diagram on page 5
Excessive Vibration and Noise:
• Damaged wheel
• Belts misaligned
• Belts too loose; worn or oily belts
• Loose fasteners
• Speed too high
• Incorrect direction of rotation. Make sure the fan rotates
in same direction as the arrows on the motor or belt drive
assembly
• Bearing setscrews loose
• Bearings need lubrication or replacement
• Debris in impeller
• Fan surge
• See page 4 for issues regarding use of VFD
Overheated Motor:
• Motor improperly wired
• Incorrect direction of rotation. Make sure the fan rotates
in same direction as the arrows on the motor or belt drive
assembly
• Cooling air diverted or blocked
• Improper inlet clearance
• Incorrect fan speed
• Incorrect voltage
Overheated Bearings:
• Improper bearing lubrication
• Excessive belt tension
SEE DETAIL A
PRE-MACHINED SHOULDER
DETAIL A

9QMX IO&M B51092-005
Parts List
QMX/QMXDHP/QMXHP/QMXD/QMXXP
15
1
16
14
17
29
18
19
20
21
1
2
3
4
5
6
7
8
9
10
11
12
13
14
12
22
23
24
Vertical Mount
4
28
31
25
10
26 30
27
Horizontal Mount
Direct Drive Level 1
Horizontal Mount
Part No. Description Part No. Description Part No. Description
1Companion Flange (optional) 16 Bearing Cover 31 Taper Lock Bushing
2External Inlet Vane Damper (optional) 17 Bearings (two required)
3 Inlet Spiral Guard or Safety Screen (optional) 18 Isolator (four required optional)
4 Inlet Cone 19 Isolation Rails - Horizontal Mount (optional)
5Mixed Flow Wheel 20 Base - Horizontal Mount (QMX)
6Shaft 21 Thrust Restraint - Horizontal Mount (optional)
7Access Door (optional) 22 Isolation Structure - Vertical Mount (optional)
8 Motor Cover (optional) 23 Housing - Vertical Mount (QMX)
9Housing-Horizontal Mount (QMX) 24 Shaft Locking Collar - Vertical Mount
10 Motor 25 Housing - Direct Drive
11 Motor Plate (QMX) 26 Base - Direct Drive
12 Belt Guard 27 Motor Cover - Direct Drive
13 Belt Set 28 Mix-Flow Wheel - Direct Drive
14 Sheaves 29 Horizontal Split Housing (optional)
15 Discharge Safety Screen (optional) 30 Mounting Feet - Level 1 Horizontal Mount

10QMX IO&M B51092-005
QMXE/QMXHPE
1
2
3
4
5
6
Part No. Description
1 QMX Curb Cap
2QMXE Birdscreen
3 QMXE Top Cap Post
4QMXE Ba󰀪e Brace
5 QMXE Top Cap Extension (for size 90 only)
6 QMXE Top Cap
See common parts (not shown) listed on page 9.
QMXS/QMXHPS
1
2
3
4
5
6
7
8
9
Part No. Description
1 QMX Curb Cap
2 QMXS Top Cap - Open
3QMXS Upper Ba󰀪e Brace
4 QMXS Top Cap Post
5QMXS Birdscreen
6 QMXS Top Cap
7 QMXS Lower Top Cap Post
8QMXS Lower Ba󰀪e Brace
9 QMXS Adapter Plate
See common parts (not shown) listed on page 9.

11QMX IO&M B51092-005
QMXU/QMXHPU
5
4
2
1
3
6
Part No. Description
1 QMX Curb Cap
2 QMXU Lifting Lug
3QMXU Damper
4QMXU Damper Stop
5QMXU Windband
6QMXU Discharge Guard (optional)
See common parts (not shown) listed on page 9.
QMXLE/QMXHPLE
1
2
3
4
5
6
7
Part No. Description
1 QMXLE Mixing Box
2QMXLE Curb Cap
3QMXLE Middle Section
4 QMXLE Adapter Plate
5 QMXLE Stack Damper
6QMXLE Windband
7 QMXLE Lifting Lug
See common parts (not shown) listed on page 9.

12QMX IO&M B51092-005
Limited Warranty
Loren Cook Company warrants that your Loren Cook fan was manufactured free of defects in materials and workmanship, to the extent stated herein.
For a period of one (1) year after date of shipment, we will replace any parts found to be defective without charge, except for shipping costs which will be
paid by you. This warranty is granted only to the original purchaser placing the fan in service. This warranty is void if the fan or any part thereof has been
altered or modied from its original design or has been abused, misused, damaged or is in worn condition or if the fan has been used other than for the
uses described in the company manual. This warranty does not cover defects resulting from normal wear and tear. To make a warranty claim, notify Loren
Cook Company, General O󰀩ces, 2015 East Dale Street, Springeld, Missouri 65803-4637, explaining in writing, in detail, your complaint and referring to
the specic model and serial numbers of your fan. Upon receipt by Loren Cook Company of your written complaint, you will be notied, within thirty (30)
days of our receipt of your complaint, in writing, as to the manner in which your claim will be handled. If you are entitled to warranty relief, a warranty ad-
justment will be completed within sixty (60) business days of the receipt of your written complaint by Loren Cook Company. This warranty gives only the
original purchaser placing the fan in service specically the right. You may have other legal rights which vary from state to state. For fans provided with
motors, the motor manufacturer warrants motors for a designated period stated in the manufacturer’s warranty. Warranty periods vary from manufacturer
to manufacturer. Should motors furnished by Loren Cook Company prove defective during the designated period, they should be returned to the nearest
authorized motor service station. Loren Cook Company will not be responsible for any removal or installation costs.
Corporate O󰀩ces: 2015 E. Dale St. Springeld, MO 65803
Phone [phone] | Fax [phone] | lorencook.com
July 2020
Arrangement 3
1
2
3
4
5
6
Part No. Description
1 Arr. 3 Bearing Support
2 Arr. 3 Shaft
3Arr. 3 Spiral Guard
4 Arr. 3 Base
5 Arr. 3 Housing
6 Arr. 3 Motor Cover
See common parts (not shown) listed on page 9.