FloAire NSA User Manual

Standard and Modular Centrifugal Untempered Supply Fans

Installation, Operation, and Maintenance Manual

Standard Untempered Supply Fan

Modular Untempered Supply Fan

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RECEIVING AND INSPECTION

WARNING!!

INLINE Filtered Supply Fan

Upon receiving unit, check for any interior and exterior damage, and if found, report it
immediately to the carrier. Also check that all accessory items are accounted for and are
damage free. Turn the blower wheel by hand to verify free rotation and check the damper (if
supplied) for free operation.

Installation of this ventilator should only be performed by a qualified professional who has
read and understands these instructions and is familiar with proper safety precautions.
Improper installation poses serious risk of injury due to electric shock, contact with rotating
equipment, and other potential hazards. Read this manual thoroughly before installing or
servicing this equipment. ALWAYS disconnect power prior to working on fan.

. This document is the property of the owner of this equipment and is
required for future maintenance. Leave this document with the owner when installation or
service is complete.

November 2012 Rev. 12

A0011038

TABLE OF CONTENTS

WARRANTY .................................................................................................................................................. 3

INSTALLATION ............................................................................................................................................. 4

Mechanical ................................................................................................................................................ 4

Site Preparation .................................................................................................................................... 4

Intake Assembly ................................................................................................................................... 4

Curb and Ductwork ............................................................................................................................... 4

Recommended Supply Ductwork Sizes ............................................................................................... 4

Roof Mount Installation ......................................................................................................................... 5

Wall Mount Installation ......................................................................................................................... 5

Indoor (Inline) Installation ..................................................................................................................... 6

Installation with Exhaust Fan ................................................................................................................ 6

Electrical ................................................................................................................................................... 7

Copper Wire Ampacity ......................................................................................................................... 7

PSC (Permanent Split Capacitor) Motor Speed Control ...................................................................... 8

ECM (Electronically Controlled Motor) Speed Control ......................................................................... 8

Motorized Intake Damper ..................................................................................................................... 8

Fan to Building Wiring Connection ....................................................................................................... 9

OPERATION ............................................................................................................................................... 10

Start Up ................................................................................................................................................... 10

Special Tools Required ...................................................................................................................... 10

Start Up Procedure ............................................................................................................................. 10

Pulley Setscrew Torque ..................................................................................................................... 11

Pulley Adjustment ............................................................................................................................... 11

Pulley Alignment ................................................................................................................................. 11

Proper Belt Tension ............................................................................................................................ 11

Pulley Combination Chart ................................................................................................................... 12

Re-Circulating Control Options ............................................................................................................... 13

Manual Positioning Control (Potentiometer) ...................................................................................... 13

Two Position Control .......................................................................................................................... 13

Static Pressure Control (Photohelic) .................................................................................................. 13

A306 Outdoor Sensor ......................................................................................................................... 14

Building Signal Damper Control ......................................................................................................... 14

Troubleshooting ...................................................................................................................................... 15

Troubleshooting Chart ........................................................................................................................ 15

MAINTENANCE .......................................................................................................................................... 16

General Maintenance ............................................................................................................................. 16

2 weeks after startup .............................................................................................................................. 16

Every 3 months ....................................................................................................................................... 16

Filter Quantity Chart ........................................................................................................................... 17

Yearly ...................................................................................................................................................... 17

Start-Up and Maintenance Documentation ............................................................................................ 18

Job Information ................................................................................................................................... 18

Fan Unit Information ........................................................................................................................... 18

Maintenance Record .......................................................................................................................... 18

Factory Service Department ............................................................................................................... 18

2

WARRANTY

This equipment is warranted to be free from defects in materials and workmanship, under normal use and
service, for a period of 12 months from date of shipment. This warranty shall not apply if:

1. The equipment is not installed by a qualified installer per the MANUFACTURER’S installation
instructions shipped with the product,

2. The equipment is not installed in accordance with federal, state and local codes and regulations,

3. The equipment is misused or neglected,

4. The equipment is not operated within its published capacity,

5. The invoice is not paid within the terms of the sales agreement.

The MANUFACTURER shall not be liable for incidental and consequential losses and damages
potentially attributable to malfunctioning equipment. Should any part of the equipment prove to be
defective in material or workmanship within the 12-month warranty period, upon examination by the
MANUFACTURER, such part will be repaired or replaced by MANUFACTURER at no charge. The
BUYER shall pay all labor costs incurred in connection with such repair or replacement. Equipment shall
not be returned without MANUFACTURER’S prior authorization and all returned equipment shall be
shipped by the BUYER, freight prepaid to a destination determined by the MANUFACTURER.

3

INSTALLATION

It is imperative that this unit is installed and operated with the designed airflow and electrical supply in
accordance with this manual. If there are any questions about any items, please call the service
department at 1-866-784-6900 for warranty and technical support issues.

Mechanical

WARNING: DO NOT RAISE VENTILATOR BY THE INTAKE HOOD, BLOWER OR
MOTOR SHAFT, OR BEARINGS – USE LIFTING LUGS PROVIDED OR A SLING

Site Preparation

1. Provide clearance around installation site to safely rig and lift equipment into its final position.
Supports must adequately support equipment. Refer to manufacturer’s estimated weights.

2. Consider general service and installation space when locating unit.

3. Locate unit close to the space it will serve to reduce long, twisted duct runs.

4. Do not allow air intake to face prevailing winds. Support unit above ground or at roof level high
enough to prevent precipitation from being drawn into its inlet. The inlet must also be located at
least 10 feet away from any exhaust vents. The fan inlet shall be located in accordance with the
applicable building code provisions for ventilation air.

Intake Assembly

Filters and intake hoods for standard supply fans are shipped inside the supply fan housing for protection
during shipping. Modular intakes are shipped on a separate skid. Upon unit arrival, follow the following
procedure to assemble the intake to the fan:

1. Remove the fan top (standard supply fans
only).

2. Remove the intake hood and filters from the
fan housing.

3. Re-install the fan top (standard supply fans
only).

4. Apply silicone or weather-proof gasket on the
back side of the flanges of the intake hood.

5. Screw the flanges of the intake hood to the
unit at the hatched areas shown with the
supplied sheet metal screws. Place caulk on
the outside of the screws to prevent water
leaks. Slide the filters down the filter track as
shown.

Curb and Ductwork

This fan was specified for a specific CFM and static
pressure. The ductwork attached to this unit will
significantly affect the airflow performance.
Flexible ductwork and square elbows should not be
used. Also, transitions and turns in ductwork near
the fan outlet will cause system effect and will
drastically increase the static pressure and reduce
airflow. The chart to the right shows the minimum
fan outlet duct sizes and straight lengths
recommended for optimal fan performance.

FAN TOP

INTAKE HOOD

FILTER(S)

SUPPLY FAN

Recommended Supply Ductwork Sizes

Blower Size Duct Size Straight Duct Length

10 14 x 14 48 in.
12 16 x 16 54 in.
15 20 x 20 72 in.
18 24 x 24 86 in.
20 26 x 26 108 in.
25 32 x 32 168 in.

4

Follow SMACNA guides and recommendations for the remaining duct run. Fans designed for
rooftop installation should be installed on a prefabricated or factory built roof curb. Follow curb
manufacturer’s instructions for proper curb installation. The unit should be installed on a curb and/or rail
elevated not less than 14” above any surface. Be sure duct connection and fan outlet are properly
aligned and sealed. Secure fan to curb through vertical portion of the ventilator base assembly flange
using a minimum of eight (8) lug screws, anchor bolts, or other suitable fasteners (not furnished). Shims
may be required depending upon curb installation and roofing material. Check all fasteners for tightness.
The diagrams below show different mechanical installation configurations.

Roof Mount Installation

Wall Mount Installation

5

Indoor (Inline) Installation

Installation with Exhaust Fan

6

Electrical

WARNING!!

Before connecting power to the fan, read and understand this
entire section of this document. As-built wiring diagrams are
furnished with each fan by the factory, and are attached either
to the door of the unit or the blower.

Electrical wiring and connections should be done in
accordance with local ordnances and the National Electric
Code, ANSI/NFPA70. Be sure the voltage and phase of the
power supply and the wire amperage capacity is in accordance

with the motor nameplate. For additional safety information
refer to AMCA publication 410-96, Recommended Safety

Practices for Users and Installers of Industrial and Commercial
Fans.

1. Always disconnect power before working on or near a
fan. Lock and tag the disconnect switch or breaker to
prevent accidental power up.

2. An electrical drop containing the line voltage power
wiring is shipped with every fan. The electrical drop
should be brought through one of the conduit openings
located in the base of the unit, run through the curb,
and connected to a junction box inside
the building.

3. A dedicated branch circuit should supply
the motor circuit with short circuit
protection according to the National
Electric Code. This dedicated branch
should be run to the junction box
mentioned above and connected as
shown in a following illustration labeled
“Fan to Building Wiring Connection”.

4. Make certain that the power source is
compatible with the requirements of your
equipment. The fan nameplate identifies the proper phase and voltage of the motor.

5. Before connecting fan to building power source, verify power line wiring is de-energized.

6. Secure the power cable to prevent contact with sharp objects.

7. Do not kink power cable and never allow the cable to come in contact with oil, grease, hot
surfaces or chemicals.

8. Before powering up fan check fan wheel for free rotation and make sure that the interior of the fan
is free of loose debris or shipping materials.

9. If any of the original wire supplied with the fan must be replaced, it must be replaced with type
THHN wire or equivalent.

Disconnect power before
installing or servicing fan. High
voltage electrical input is
needed for this equipment. This
work should be performed by a
qualified electrician.

Copper Wire Ampacity

Wire Size AWG Maximum Amps

14 15
12 20
10 30

8 50
6 65
4 85

7

PSC (Permanent Split Capacitor) Motor Speed Control

Some single phase direct drive fans contain speed controls that regulate the
amount of voltage going to the motor. Specific PSC motors must be used in
conjunction with speed controls. The speed control has a knob with an off position,
and high to low range. At high speed, the speed control allows all of the line
voltage to pass right to the motor.

A minimum speed adjustment is provided to allow independent control of the
minimum speed setting. Minimum speed adjustment ensures motor runs with
sufficient torque to prevent stalling. To adjust this:

1) Motor must be in actual operating conditions to achieve proper speed
adjustment. Motor will not slow down unless proper load is applied.

2) Turn main control knob to lowest speed position.

3) Locate and adjust minimum speed setting and adjust with small screw driver. This can be found
under the speed control faceplate. (rotate clockwise to decrease minimum speed; counter­clockwise to increase minimum speed).

4) Motor will now operate from this preset minimum speed to full speed.

The lowest minimum voltage that may be applied to these motors is 65VAC. Running lower
voltages to the motor can cause premature failure and overheating problems.

ECM (Electronically Controlled Motor) Speed Control

ECM motors and control allows accurate manual adjustment of fan speed.
The benefit of ECM motors is exceptional efficiency, performance, and
motor life.

The control used with ECM motors features a 4 digit LED numerical
display. The blue knob on the control allows the user to set the flow index
with a screwdriver. Twenty seconds later, the display shows the motor
RPM. Then, the display periodically alternates between the flow index and
motor RPM. The flow index has a range of 0 to 100% and is typically linear with motor RPM.

The ECM control requires a 24 VAC input and can locally turn the motor on and off. The motor can be
adjusted between 300 RPM and maximum speed with this control.

NOTE: To adjust the speed of 3 phase direct drive motors, a variable frequency
drive is required.

Motorized Intake Damper

On units shipped with the optional motorized intake damper, a power transformer is supplied with the unit
if the main incoming voltage is greater than 120V. The damper motor is automatically energized when
the main disconnect switch is in the ON position. No external wiring to the damper motor is required.

8

Fan to Building Wiring Connection

9

10

Maximum RPM and HP Chart

Pulley Adjustment Illustration

OPERATION

Prior to starting up or operating the ventilator, check all fasteners for tightness. In particular, check the set
screw in the wheel hub, bearings and the fan sheaves (pulleys). With power to the fan OFF or prior to
connecting ventilator to power, turn the fan wheel by hand to be sure it is not striking the inlet or any
obstacles. Re-center if necessary.

Start Up

Special Tools Required

• AC Voltage Meter

• Tachometer

• Amperage Meter

• Standard Hand Tools

Start Up Procedure

1. Check all electrical connections for tightness and continuity.

2. Check pulley alignment and belt tension as described below.

3. Inspect the condition of the intake damper and damper linkage, if provided.

4. Inspect the air-stream for obstructions and install intake filters if missing.

5. Compare the supplied voltage with the fan’s nameplate voltage. If this does not match, correct
the problem.

6. Start the fan up, by turning the external disconnect to the ON position, and shut it OFF
immediately to check rotation of the wheel with the directional arrow on the blower scroll.
Reversed rotation will result in poor air performance, motor overloading and possible burnout.
For units equipped with a single-phase motor check the motor wiring diagram to change rotation.
For 3-phase motors, any two power leads can be interchanged to reverse motor direction.

7. When the fan is started up, observe the operation and check for any unusual noises.

8. Switch the external disconnect back to the ON position and with the air system in full operation
and all ducts attached, measure the system airflow. Motor sheave (pulley) is variable pitch, and
allows for an increase or decrease of the fan RPM to adjust the airflow, as shown in the
illustration below. For your convenience, a RPM chart is included in the following pages.

9. Once the proper airflow is achieved, measure and record the fan speed with a reliable
tachometer. Caution - Excessive speed will result in motor overloading or bearing failure.
Do not set fan RPMs higher than specified in the maximum RPM chart. See the
troubleshooting guide for more information.

10. Measure and record the voltage and amperage to the motor and compare with the motor
nameplate to determine if the motor is operating under safe load condition.

11. Once the rpm of the ventilator has been properly set, disconnect power and recheck belt tension
and pulley alignment as described below.

Blower Size Maximum RPM Maximum HP

10” 1800 2
12” 1500 3
15” 1400 5
18” 1200 5
20” 1000 10
25” 900 20

11

Pulley Adjustment

The adjustable motor pulley is factory set for the RPM specified.
Speed can be increased by closing or decreased by opening the
adjustable motor sheave. Two groove variable pitch pulleys must
be adjusted an equal number of turns open or closed. Any
increase in speed represents a substantial increase in
horsepower required by the unit. Motor amperage should always
be checked to avoid serious damage to the motor when the
speed is varied. Always torque setscrews according to the
setscrew torque chart.

Pulley Alignment

Pulley Setscrew Torque

Thread Size Torque (IN/Lb)

No. 10 (bushing) 32

1/4” (bushing) 72

5/16” 130

Proper Belt Tension

12

Pulley Combination Chart

** 2HP Motors on 20 IN Blowers use 2 VP42 Pulleys

Motor RPM 1725

1/3 to 1-1/2 HP MOTOR PULLEY Dd1 Dd2 Pd1 Pd2

AX BELTS 1VL34 1.9 2.9 2 3

BLOWER PULLEY DATUM DIAMETER PITCH DIAMETER 5 4 1/2 4 3 1/2 3 2 1/2 2 1 1/2 1 1/2 0

AK114 11 11.2 308 323 339 354 370 385 400 416 431 447 462

1/3 to 2 HP MOTOR PULLEY Dd1 Dd2 Pd1 Pd2
AX BELTS 1VL40 2.4 3.4 2.6 3.6

BLOWER PULLEY DATUM DIAMETER PITCH DIAMETER 5 4 1/2 4 3 1/2 3 2 1/2 2 1 1/2 1 1/2 0

AK114 11 11.2 400 416 431 447 462 477 493 508 524 539 554

AK94 9 9.2 488 506 525 544 563 581 600 619 638 656 675

AK79 7.5 7.7 582 605 627 650 672 694 717 739 762 784 806

AK66 6.2 6.4 701 728 755 782 809 836 863 889 916 943 970

AK54 5 5.2 863 896 929 962 995 1028 1062 1095 1128 1161 1194

AK46 4.2 4.4 1019 1059 1098 1137 1176 1215 1255 1294 1333 1372 1411

AK39 3.5 3.7 1212 1259 1305 1352 1399 1445 1492 1539 1585 1632 1678
AK32 3 3.2 1402 1455 1509 1563 1617 167 1 1725 1779 1833 1887 1941

3 to 5 HP MOTOR PULLEY Dd1 Dd2 Pd1 Pd2

BX BELTS 2VP42 2.9 3.9 3 4

BLOWER PULLEY DATUM DIAMETER PITCH DIAMETER 6 5 1/2 5 4 1/2 4 3 1/2 3 2 1/2 2 1 1/2 1 1/2 0

2BK160H 15.4 15.7 330 339 348 35 7 366 375 385 394 403 412 421 430 439

2BK140H 13.4 13.7 378 388 399 40 9 420 430 441 451 462 472 483 493 504

2BK120H 11.4 11.7 442 455 467 47 9 491 504 516 528 541 553 565 577 590

2BK110H 10.4 10.7 484 497 511 52 4 537 551 564 578 591 605 618 631 645

2BK100H 9.4 9.7 534 548 563 578 593 608 622 637 652 6 67 682 697 711

2BK90H 8.4 8.7 595 611 628 644 661 677 694 710 727 7 44 760 777 793

2BK80H 7.4 7.7 672 691 709 728 747 765 784 803 821 8 40 859 877 896

2BK70H 6.4 6.7 772 794 815 837 858 880 901 923 944 9 65 987 10 08 1030

10 - 20 IN. BLOWER**

2BK60H 5.4 5.7 908 933 958 984 1009 1034 1059 1084 1110 1135 1160 1185 1211

2BK55H 4.9 5.2 995 1023 1050 1078 1106 1133 1161 1189 1216 1244 1272 1299 1327

2BK50H 4.4 4.7 1101 1132 1162 1193 1223 1254 1285 1315 1346 1376 1407 1438 1468

7-1/2 to 10 HP M OTOR PULLEY Dd1 Dd2 Pd1 Pd2

BX BELTS 2VP60 4.3 5.5 4.7 5.9

BLOWER PULLEY DATUM DIAMETER PITCH DIAMETER 6 5 1/2 5 4 1/2 4 3 1/2 3 2 1/2 2 1 1/2 1 1 /2 0

2BK160H 15.4 15.7 516 527 538 54 9 560 571 582 593 604 615 626 637 648

2BK140H 13.4 13.7 592 604 617 63 0 642 655 667 680 693 705 718 730 743

2BK120H 11.4 11.7 693 708 722 73 7 752 767 781 796 811 826 840 855 870

2BK110H 10.4 10.7 758 774 790 80 6 822 838 854 871 887 903 919 935 951

2BK100H 9.4 9.7 836 854 871 889 907 925 943 960 978 9 96 1014 1031 104 9

2BK90H 8.4 8.7 932 952 972 991 1011 1031 1051 1071 1091 1110 1130 1150 1170

2BK80H 7.4 7.7 1053 1075 1098 1120 1143 1165 1187 1210 1232 1255 1277 1299 1322

3 to 5 HP MOTOR PULLEY Dd1 Dd2 Pd1 Pd2
BX BELTS 2VP42 2.9 3.9 3 4

BLOWER PULLEY DATUM DIAMETER PITCH DIAMETER 6 5 1/2 5 4 1/2 4 3 1/2 3 2 1/2 2 1 1/2 1 1 /2 0

2B5V278 27.8 28.1 184 189 194 200 205 210 215 220 225 230 235 240 246

2B5V250 25 25.3 205 210 216 222 227 233 239 244 250 256 261 267 273

2B5V234 23.4 23.7 218 224 230 237 243 249 255 261 267 273 279 285 291

2B5V200 20 20.3 255 262 269 276 283 290 297 304 312 319 326 333 340

2B5V184 18.4 18.7 277 284 292 300 307 315 323 331 338 346 354 361 369

2B5V160 16 16.3 317 326 335 344 353 362 370 379 388 397 406 414 423

2B5V154 15.4 15.7 330 339 348 357 366 375 385 394 403 412 421 430 439

2B5V136 12.6 12.9 401 412 423 435 446 457 468 479 490 501 513 524 535

2B5V124 12.4 12.7 407 419 430 441 453 464 475 487 498 509 521 532 543

2B5V110 11 11.3 458 471 483 496 509 522 534 547 560 572 585 598 611

7-1/2 to 10 HP M OTOR PULLEY Dd1 Dd2 Pd1 Pd2
BX BELTS 2VP60 4.3 5.5 4.7 5.9

BLOWER PULLEY DATUM DIAMETER PITCH DIAMETER 6 5 1/2 5 4 1/2 4 3 1/2 3 2 1/2 2 1 1/2 1 1 /2 0

2B5V278 27.8 28.1 289 295 301 307 313 319 325 331 338 344 350 356 362

2B5V250 25 25.3 320 327 334 341 348 355 361 368 375 382 389 395 402

2B5V234 23.4 23.7 342 349 357 364 371 378 386 393 400 408 415 422 429

2B5V200 20 20.3 399 408 416 425 433 442 450 459 467 476 484 493 501

2B5V184 18.4 18.7 434 443 452 461 470 480 489 498 507 517 526 535 544

2B5V160 16 16.3 497 508 519 529 540 550 561 571 582 593 603 614 624

2B5V154 15.4 15.7 516 527 538 549 560 571 582 593 604 615 626 637 648

25 IN. BLOWER

2B5V136 12.6 12.9 628 642 655 669 682 695 709 722 735 749 762 776 789

2B5V124 12.4 12.7 638 652 666 679 693 706 720 733 747 761 774 788 801

2B5V110 11 11.3 717 733 748 763 779 794 809 824 840 855 870 885 901

15 to 20 HP MOTOR PULLEY Dd1 Dd2 Pd1 Pd2
BX BELTS 2VP75 5.8 7 6.2 7.4

BLOWER PULLEY DATUM DIAMETER PITCH DIAMETER 6 5 1/2 5 4 1/2 4 3 1/2 3 2 1/2 2 1 1/2 1 1 /2 0

2B5V278 27.8 28.1 381 387 393 399 405 411 417 424 430 436 442 448 454

2B5V250 25 25.3 423 430 436 443 450 457 464 470 477 484 491 498 505

2B5V234 23.4 23.7 451 459 466 473 480 488 495 502 509 517 524 531 539

2B5V200 20 20.3 527 535 544 552 561 569 578 586 595 603 612 620 629

2B5V184 18.4 18.7 572 581 590 600 609 618 627 636 646 655 664 673 683

2B5V160 16 16.3 656 667 677 688 698 709 720 730 741 751 762 773 783

2B5V154 15.4 15.7 681 692 703 714 725 736 747 758 769 780 791 802 813
2B5V136 12.6 12.9 829 842 856 869 883 896 909 923 936 949 963 976 990

Open Closed

Open Closed

Open Closed

Open Closed

Open Closed

Open Closed

Open Closed

TURNS ON MOTOR PULLEY

TURNS ON MOTOR PULLEY

TURNS ON MOTOR PULLEY

TURNS ON MOTOR PULLEY

TURNS ON MOTOR PULLEY

TURNS ON MOTOR PULLEY

TURNS ON MOTOR PULLEY

13

Re-Circulating Control Options

Manual Positioning Control (Potentiometer)

The dampers can be controlled at a remote location by a manual potentiometer to any position from 20%
to 100% fresh air. This will allow manually setting the dampers to match the building ventilation
requirements. It will take an extra 3 control wires at the remote location. On a power failure, or if the unit is
turned off, the return air damper will close by spring return.

Two Position Control

The dampers can be controlled by a two position switch (a field supplied switching device) to open the
fresh air to 100%. On opening of the circuit, power failure, or if the unit is shutoff, the return air damper
will close by spring return.

Static Pressure Control (Photohelic)

The dampers can be controlled by a building static pressure control. This controller will sense the
difference between pressure inside the building, and pressure outside the building (sensed at the A306
outdoor sensor), and position the dampers to maintain the pressure setting on the controller. The
controller has two set points and an indicator. The two set points are a minimum desired static pressure
point, and a maximum static pressure point.

The actual building static pressure will be shown by a visual indicator between these two settings. The
controller will modulate the dampers to maintain a static pressure between these set points.

When building static pressure is below the minimum setting, the damper motor will proportionally open
the fresh air damper and close the return air damper until static increases above the minimum setting. At
this point, the damper motor will stop and hold this proportion.

If the building static continues to climb and goes above maximum setting, the damper motor will reverse
proportion, closing the fresh air damper and opening the return air damper until static drops below
maximum setting.

During the “OFF” or “Night” cycle of the unit, an internal switching circuit will close the return air damper.
See additional wiring and installation information on the static pressure controller and A306 outdoor

sensor.

Static Pressure Controller Installation Instructions

Avoid locating the front of the static pressure controller in sun light or other areas with high ambient light
or corrosive levels. Bright light shining on the photocells can cause false actuation of the load relays.

The static pressure controller should be zeroed out before attaching the low and high pressure hoses.
The zero adjustment is located between the minimum and maximum dials.

14

Using the supplied rubber tubing the high side of the static pressure controller should be plumbed to the
inside of the building. The low side of the static pressure controller should be plumbed to the A306
outdoor sensor. See the A306 installation instructions.

A306 Outdoor Sensor

Use the installation instructions shipped with the A306 outdoor sensor.

Building Signal Damper Control

When this option is ordered, the supply and return dampers will modulate based on a 0-10 VDC signal
from the Building automation system.

15

Troubleshooting

The following table lists causes and corrective actions for possible problems with the fan units. Review
this list prior to consulting manufacturer.

Troubleshooting Chart

Problem

Fan Inoperative Blown fuse or open circuit breaker Replace fuse or reset circuit

Motor Overload Fan rotating in the wrong direction Be sure fan is rotating in the

Insufficient Airflow Fan rotating in the wrong direction Be sure fan is rotating in the

Excessive Airflow Blower speed to high Reduce fan RPM

Excessive Vibration and Noise Misaligned pulleys Align pulleys

Potential Cause

Disconnect switch in “Off” position Turn to “On” position
Motor wired incorrectly Check motor wiring to wiring

Broken fan belt Replace belt
Motor starter overloaded Reset starter and check amps

Fan speed is too high Reduce fan RPM
Motor wired incorrectly Check motor wiring to wiring

Overload in starter set too low Set overload to motor FLA value
Motor HP too low Determine if HP is sufficient for

Duct static pressure lower than
design

Poor outlet conditions There should be a straight clear
Intake damper not fully open Inspect damper linkage and
Duct static pressure higher than

design
Blower speed too low Increase fan RPM. Do not

Supply grills or registers closed Open and adjust
Dirty or clogged filters Clean and/or replace
Belt slippage Adjust belt tension

Filters not installed Install filters
Duct static pressure lower than
design

Damaged or unbalanced wheel Replace wheel
Fan is operating in the unstable
region of the fan curve
Bearings need lubrication or
replacement
Fan speed is too high Reduce fan RPM
Belts too loose, worn or oily Inspect and replace if needed

Corrective Action

breaker and check amps

diagram located on fan motor

direction shown on rotation label

diagram located on fan motor

job
Reduce fan RPM

direction shown on rotation label
duct at the outlet
replace damper motor if needed

Improve ductwork to eliminate or
reduce duct losses

overload motor

Reduce fan RPM

Refer to performance curve for
fan
Lubricate or replace

16

MAINTENANCE

To guarantee trouble free operation of this fan, the manufacturer suggests following these guidelines.
Most problems associated with fan failures are directly related to poor service and maintenance.

Please record any maintenance or service performed on this fan in the documentation section located at
the end of this manual.

WARNING: DO NOT ATTEMPT MAINTENANCE ON THE FAN UNTIL THE
ELECTRICAL SUPPLY HAS BEEN COMPLETELY DISCONNECTED

General Maintenance

1. Fan inlet and approaches to ventilator should be kept clean and free from any obstruction.

2. Motors are normally permanently lubricated. Check bearings periodically. If they have grease
fittings lubricate each season. Use caution when lubricating bearings, wipe the fittings clean, the
unit should be rotated by hand while lubricating. Caution: Use care when touching the exterior

of an operating motor. Motors normally run hot and may be hot enough to be painful or
cause injury.

3. All fasteners should be checked for tightness each time maintenance checks are preformed prior
to restarting unit.

4. Blowers require very little attention when moving clean air. Occasionally oil and dust may
accumulate causing imbalance. If the fan is installed in a corrosive or dirty atmosphere,
periodically inspect and clean the wheel, inlet and other moving parts to ensure smooth and safe
operation.

2 weeks after startup

1. Belt tension should be checked after the first 2 weeks of fan operation. Belts tend to stretch and
settle into pulleys after an initial start-up sequence. Do not tension belts by changing the
setting of the motor pulley, this will change the fan speed and may damage the motor. To re­tension belts, turn the power to the fan motor OFF. Loosen the fasteners that hold the blower
scroll plate to the blower. Rotate the motor to the left or right to adjust the belt tension. Belt
tension should be adjusted to allow 1/64” of deflection per inch of belt span. Exercise extreme
care when adjusting V-belts as not to misalign pulleys. Any misalignment will cause a sharp
reduction in belt life and produce squeaky noises. Over-tightening will cause excessive belt and
bearing wear as well as noise. Too little tension will cause slippage at startup and uneven wear.

Whenever belts are removed or installed, never force belts over pulleys without loosening
motor first to relieve belt tension. When replacing belts, use the same type as supplied by the

manufacturer. On units shipped with double groove pulleys, matched belts should always be
used.

2. All fasteners should be checked for tightness each time maintenance checks are preformed prior
to restarting unit.

Every 3 months

1. Belt tension should be checked quarterly. See instructions in the previous maintenance section.
Over-tightening will cause excessive bearing wear and noise. Too little tension will cause
slippage at startup and uneven wear.

2. Filters need to be cleaned and/or replaced quarterly, and more often in severe conditions.
Washable filters can be washed in warm soapy water. When re-installing filters, be sure to install
with the airflow in the correct direction as indicated on the filter.

17

Filter Quantity Chart

Intake

16” x 20”

20” x 25”

4

2

4

4

9

1

1

2

2

3

Size 1 Standard Sloped 2
Size 2 Standard Sloped 2
Size 1 Modular Sloped 3
Size 2 Modular Sloped 3
Size 3 Modular Sloped 6
Size 4 Modular Sloped 10
Size 5 Modular Sloped 8
Size 1 V-Bank 3
Size 2 V-Bank 8
Size 3 V-Bank 8
Size 4 V-Bank 15
Size 5 V-Bank 12
Size 1 INLINE 1
Size 2 INLINE 1
Size 3 INLINE 2

Optional Mixing Box Filters

Diagonal Filters

Unit Size Filter Quantity Filter Size

1

2

3

4

5

10 x 16

20 x 25

15 X 20

18 X 25

14.5 x 19

Vertical Filters

Unit Size Filter Quantity Filter Size

1

2

3

4

5

10 x 16

16 x 25

15 x 15

16 x 20

14.5 x 19

Yearly

1. Inspect bearings for wear and deterioration. Replace if necessary.

2. Inspect belt wear and replace torn or worn belts.

3. Inspect bolts and set screws for tightness. Tighten as necessary.

4. Inspect motor for cleanliness. Clean exterior surfaces only. Remove dust and grease from the
motor housing to ensure proper motor cooling. Remove dirt and grease from the wheel and
housing to prevent imbalance and damage.

18

Start-Up and Maintenance Documentation

START-UP AND MEASUREMENTS SHOULD BE PERFORMED AFTER THE SYSTEM HAS BEEN
AIR BALANCED (Warranty will be void without completion of this form)

Job Information

Job Name Service Company
Address Address
City City
State State
Zip Zip
Phone Number Phone Number
Fax Number Fax Number
Contact Contact
Purchase Date Start-Up Date

Fan Unit Information

Refer to the start-up procedure in this manual to complete this section.
Name Plate and Unit Information
Model Number

Serial Number
Volts
Hertz
Phase
FLA
HP
Blower Pulley
Motor Pulley

Belt Number

**

If measured amps exceed the FLA rating on the nameplate, fan RPM must be reduced to decrease the

measured amps below the nameplate FLA rating.

Field Measured Information
Voltage

Amperage**
RPM

Blower Rotation Correct
Incorrect

Maintenance Record

Date Service Performed

Factory Service Department

Phone: [phone]

Fax: [phone]

19

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