Loren Cook SQN Installation Manual

Personal Safety

Disconnect switches are recommended. Place the
disconnect switch near the fan in order that the
power can be swiftly cut off in case of an
emergency, and in order that maintenance
personnel are provided complete control of the
power source.

INSTALLATION, OPERATION, AND MAINTENANCE MANUAL

WARNING

This unit has rotating parts. Safety precautions
should be exercised at all times during installation,
operation, and maintenance.
ALWAYS disconnect power prior to working on fan.

This publication contains the installation, operation
and maintenance instructions for standard units of the
SQN-Centrifugal Square Inline Fans. Carefully read this
publication prior to any installation or maintenance pro­cedure.

Loren Cook catalog, SQN, provides additional information
describing the equipment, fan performance, available acces­sories, and specification data.

For additional safety information, refer to AMCA publication
410-96, Safety Practices for Users and Installers of Industrial
and Commercial Fans.

All of the publications listed above can be obtained from
Loren Cook Company by phoning 417.869.6474, extension
166; by FAX at 417.832.9431; or by e-mail at info@loren­cook.com.

For information on special equipment, contact Loren Cook
Company Customer Service Department at 417.869.6474.

Receiving and Inspection

Immediately, upon receipt of an SQN fan, carefully inspect
the fan and accessories for damage and shortage.

• Turn the wheel by hand to ensure it turns freely and does
not bind.

• Inspect dampers for free operation of all moving parts.

• Record on the Delivery Receipt any visible sign of dam­age.

Handling

Lift the fan by the outside housing (box). Never lift by the

shaft or motor .

SQN

Centrifugal Square Inline Fans

SQN-B

Installation

Motor Installation

To prevent damage to the fan during shipping, motors 5
HP and larger, and extremely heavy motors (cast iron or
severe duty) are shipped loose and must be field mounted.

Storage

If the fan is stored for any length of time prior to installation,
completely fill the bearings with grease or moisture-inhibiting
oil. Refer to Lubricants on page 6. Also, store the fan in its
original crate and protect it from dust, debris and the weather.

To maintain good working condition of a SQN when it is
stored outdoors, or on a construction site, follow the additiona l
steps below:

• Cover the inlet and outlet, and belt tunnel opening to pre-

vent the accumulation of dirt and moisture in the housing.

• Periodically rotate the wheel and operate dampers (if sup-

plied) to keep a coating of grease on all internal be aring p a rt s.

• Periodically inspect the unit to prevent damaging condi-

tions.

Motor Plate

Motor Plate
Adjustment Nut

Motor Plate Adjustment

T-1
T-4

Ground B

L

2

L

1

Ground A

Line

Fan

Motor

Damper

Motor*

Second
Damper

Motor

T

ransformer**

Transformer**

L3
L2
L1

Wiring Diagrams

Ground A

Ground B

T-1

T-4

Low Speed

High Speed

L

1

L

2

Line

Ground B

J-10

T-5

Ground A

Link A
Link B

Low Voltage

Line

L

2

L

1

Ground A

Link A & B

L

1

L

2

Line

Ground B

T-5

J-10

Low Speed
Low Speed
Low Speed

High Speed
High Speed
High Speed

T

3

T

2

T

1

T

11

T

12

T

13

Motor

L

1

L

2

L

3

Line

Single Speed, Single Phase Motor

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

When ground 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

Wiring Diagrams

3 Phase, 9 Lead Motor
Y-Connection

Low Voltage

208/230 Volts

4

5

6

1
728

3
9

L2L

L

3

1

To reverse, interchange any 2 line leads.

High Voltage

460 Volts

456

789

3

12

L2L

L

1

2 Speed, 1 Winding, 3 Phase Motor

High Speed

1

Together

2

Motor

3

L

4

1

L

5

2

6

L

3

To reverse, interchange any 2 line leads. Motors require magnetic control.

2 Speed, 2 Winding, 3 Phase

3 Phase, 9 Lead Motor
Delta-Connection

Low Voltage

208/230 Volts

8

7

4

6

2

1

3

Line

L

1

L

2

Motor

L

3

Low Speed

High Voltage

460 Volts

9
5

3

789
456

3

12

L

L

L

1

3

2

L

1

1

L

2

2

3

Line

L

3

4

Open

5
6

When ground required, attach to ground A or B with No. 6 thread forming
screw. To reverse, interchange T-5 and J-10 leads.

Typical Damper Motor Schematic

Wiring Installation

All wiring should be in accordance with local ordinances
and the National Electrical Code, NFPA 70. Ensure the
power supply (voltage, frequency, and current carrying
capacity of wires) is in accordance with the motor name­plate. Refer to the Wiring Diagrams.

Lock off all power sources before unit is wired to
power source.

Direct drive - Wire the electrical box on the blower hous­ing.

Belt drive - The motor can be wired directly since the
motor is external to the fan.

To reverse: High Speed-interchange leads T
Low Speed-interchange leads T
line leads.

and T2. Both Speeds-interchange any 2

1

and T12.

11

For 3 phase, damper motor voltage should be the same between L1 and

. For single phase application, disregard L3. *Damper motors may be

L

2

available in 115, 230 and 460 volt models. The damper motor nameplate
voltage should be verified prior to connection. **A transformer may be pro­vided in some installations to correct the damper motor voltage to the
specified voltage.

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 se curing motor base to power
assembly. Do not remove motor mounting bolts.

Follow the wiring diagram in the disconnect 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).

2

Not on direct drive

(C)

Not on direct drive

(B)

Not on direct drive

(A)

Not on direct drive

(D)

Not on direct drive

(E)

Figure 5

Foot Mounting Illustrations

Sizes 70 - 135

Sizes 150 - 225 Sizes 245 - 402

View of A or E Foot Assembly

Figure 4

Belt and Pulley Installation

1 foot

1/4 inch

Figure 1

Figure 2

Tolerance

Center Distance

Maximum

Gap

Up thru 12” 1/16”

12” up through 48 1/8”

Over 48” 1/4”

If your fan is a direct drive, proceed to Blower Installa-

tion.

Belt tension is determined by the sound the belts make
when the fan is first started. Belts will produce a loud
squeal which dissipates after the fan is operating at full
capacity. If the belt tension is too tight or too loose, lost effi­ciency and possible damage can occur.

Do not change the pulley pitch diameter to change ten­sion. This will result in a different fan speed.

a. Loosen motor plate adjustment nuts on L-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.

b. Adjust the motor plate until proper tension is reached.

For proper tension, a deflection of approximately 1/4”
per foot of center distance should be obtained by

firmly pressing the belt. Refer to Figure1.
c. Lock the motor plate adjustment nuts in place.
d. Ensure pulleys are properly aligned. Refer to Figure

2.

OFFSET ANGULAR OFFSET/ANGULAR

A

W

square to adjust the position of the motor pul­ley until the belt is parallel to the longer leg of
the square.

Blower Installation

The blower is shipped with the motor in the
12 o’clock position and the feet are shipped
loose.

a. Upon receipt of the fan, remove the

Figure 3

eight (8) feet shipped with the fan and ensure the feet
are the correct type. Refer to Figure 4.

b. Determine how the fan is to be mounted. Refer to

Figure 5.

c. Remove the 5/16” bolt(s) from the corner of the hous-

ing in which the foot is to be attached.

d. Place the foot over the open bolt hole(s) and bolt the

foot to the unit. Refer to Figure 4.

Pulley Alignment

setscrew and by moving the motor pulley on the motor sh aft.
for the drive alignment tolerance. All contact points (indi-

cated 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 dif­ference in width. Figure 3 illustrates using a carpenter’s

B

CENTER

DISTANCE

(CD)

GAP

GAP

X
Y

Z

Pulley alignment is adjusted by loosening the motor pulley

Figure 2 indicates where to measure the allowable gap

3

SQN Optional Side Discharge Installation

Side Discharge

Duct Connection

Collar

Rear Discharge

Block-off Panel

NOTE

Original Loren Cook Company labels must remain
with the unit. This may require swapping access
doors from one side to the other.

Recommended Torque for Setscrews/Bolts (IN/LB.)

Setscrews

Hold Down Bolts

Size

Key Hex

Across

Flats

Recommended

Torque

Min. Max. Size

Wrench

Torque

No.10 3/32” 28 33 3/8”-16 240

1/4” 1/8” 66 80 1/2”-13 600

5/16” 5/32” 126 156 5/8”-11 1200

3/8” 3/16” 228 275 3/4”-10 2100

7/16” 7/32” 29 348 7/8”-9 2040

1/2” 1/4” 42 504

5/8” 5/16” 92 1104

3/4” 3/8” 120 1440

Upon receiving a SQN for a side discharge installation,
please note that the rear discharge block-off panel is
installed on the unit and that the cor rect number of side dis­charge duct connection collars are provided (4 steel
flanges for a single side discharge and 8 for dual).

To install the side discharge duct connection collar,
remove the appropriate access door. Install the side dis­charge duct connection collar using the bolts that were
removed with the access door . Then connect the duct work.
See page 5 for examples.

Final Installation Steps

a. Ensure that all accessories are installed.
b. Ensure that the blower is secured to ductwork.
c. Inspect wheel-to-inlet clearance. Ensure wheel does

not rub against the inlet.

d. Test the fan to ensure the rotation of the wheel is the

same as indicated by the rotation label.

e. Inspect for correct amperage with an ammeter and

correct voltage with a voltmeter.

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.

Operation

Pre-Start Checks

a. Lock out all the primary and secondary power

sources.

b. Inspect and tighten fasteners and s etscrews, particu-

larly fan mounting and bearing fasteners. Refer to

Torque chart.
c. Inspect belt tension and pulley alignment.
d. Inspect motor wiring.
e. Ensure fan and ductwork are clean and free of

debris.
f. Close and secure all access doors.
g. Restore power to the fan.

Start Up

Turn the fan on. In variable speed units, set the 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.

If a problem is discovered, immediately shut the fan
off. Lock out all electrical power and check for the
cause of the trouble. See Troubleshooting on page 7.

Inspection

Inspection of the fan should be conducted at the first 30

minute, 8 hour and 24 hour intervals of satisfactory opera-

tion. During the inspections, stop the fan and inspect as per
the chart below.

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.

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 first month of operation. Fans exhausting con­taminated air (airborne abrasives) should be inspected
every three months.

Yearly inspections are recommended for fans exhausting
non-contaminated air.

It is recommended the following inspections be con­ducted twice per year.

• Inspect bolts and setscrews for tightness. Tighten as
necessary. Refer to Torque chart.

• Inspect belt wear and alignment. Replace worn belts
with new belts and adjust alignment as needed. Refer
to Belt and Pulley Installation.

• Bearings should be inspected as recommended in the
Conditions Chart.

4