General Size Ranges:

spotpullSoftware and s/w Development

Nov 2, 2013 (3 years and 11 months ago)

111 views

SECTION
15830

FANS


PART I. GENERAL

1.01

SUMMARY

A.

SECTION INCLUDES

1.

Provide materials, devices, labor and supervision necessary to install fans and
related equipment as required by the Drawings and this Section.

a.

Including special app
lications such as but not limited to AMCA Class I
minimum Ventilating sets (a.k.a. “vent sets”) utilized for special purposes such
as for laboratory and other potentially corrosive exhaust applications as well as
for explosion proof applications.

B.

RELATED D
OCUMENTS

1.

Section 15060


Hangers and Supports

2.

Section 15070


Mechanical Sound, Vibration, and Seismic Control

3.

Section 15715


Heating and Cooling Coils

4.

Section 15720


Air Handling Units

5.

Section 15820


Duct Accessories

6.

Section 15905
-

HVAC Instrumentatio
n

7.

Section 15920


Pneumatic Controls

8.

Section 15950


Testing and Balancing

9.

Section 16220
-

Motors

10.

Section 16260
-

Static Power Converters (Variable Frequency Converters only)

11.

Drawing 15800
-
1, Curb
-
Supported Fume Hood Exhaust Fan/Stack Installation

1.02

DESCRIP
TION

A.

General Size Ranges:
The intent of this article is to optimize Centrifugal Fans
associated with Air Handling Units into three groups of sizes by application and general
component market availability. Note that Division I
General Guidelines

describe a
nd
outline generally by “project” CFM, that airside economizers are needed starting around
3,000 CFM; variable air volume units
\

systems start around 5,000 CFM and heat recovery
starts around 10,000 CFM. This article therefore generally assigns units int
o three groups
as follows:

1.

A “small” unit shall be defined as the lower of either the CFM, ranging up to 3000
CFM, or 6 square feet of coil face area, whichever meets the application criteria first.

2.

A “midsize” unit shall be defined as the lower of either
the CFM ranging from 3000
CFM up to 20,000 CFM, or 6 to 40 square feet of coil face area, whichever meets the
application criteria first.

3.

A “large” unit shall be defined as anything beyond 20,000 CFM or beyond 40 square
feet.

1.03

DEFINITIONS

A.

AHU:

Air Handlin
g Unit (for purposes of coordination)

B.

Factory Fabricated:

Any such component described, as being factory fabricated, shall
be fabricated by the same Manufacturer having been in the same fabrication business at
least 5 years.

C.

Face Velocity:

Air handling
systems shall not exceed the cross sectional net free area
velocity in fpm as defined in each respective section.

D.

Net Free Area:

The area perpendicular to the airflow that is exclusive of obstructions.

A.


FSAD
-
DS:

Full Sized Access Door



1.

DS = Drive Side;

CH = Connection Hand; B = Both sides

E.

Connection Hand:

Connection hand orientation shall be configured as “The air is hitting
the back of your head in the same direction as the air flow through the unit.”

F.

Component:

Any such item such installed on or ins
ide of an AHU or other air moving
system such as a Fan.

G.

FC:

Centrifugal fan wheel and blade assembly typically using Forward Curved type single
wall blades curved blades that are pitched forward so as to push the air relative to the spin
orientation.

H.

BI:

B
ackward Incline is a type of non
-
overloading centrifugal fan wheels and blade
assembly typically using flat blades that are backwards pitched relative to the spin
orientation.

I.

AF or BAF:

Backward Inclined “BI” wheel using airfoil shaped blades. Performan
ce and
longevity characteristics are typically better than BI or FC (Forward curved Centrifugal
wheels.)

J.

Vibration


Free:

Furnish and erect fans free of vibration and pulsations as they pertain
to the class designation of the respective system.

K.

Metal Lin
ers:

For fans used in conjunction with plenum style housings, all internal walls,
ceiling and floor surfaces of the Housing shall have metal covering all insulation. No
exposed insulation shall be allowed. Foil faced insulation shall not be used in lieu
of metal
inner liner. All air
-
moving systems are to have solid metal liners (use of perforated metal
liners requires pre
-
approval from Engineering Services, UIUC Operations and Maintenance
Division).

L.

Access Sections:

Access sections shall be provided wit
h factory
-
fabricated full
-
sized
hinged and latched doors for access upstream and in between installed components.

M.

Access Doors:

Access Doors shall be full
-
sized, insulated, hinged and latched, double
-
walled, factory fabricated incorporating bulb type seal
s. Single door sections shall have
the door located on the same side as the motor and drive location unless specified
otherwise. Each door shall swing so the unit air pressure will hold them closed.

1.04

REFERENCES

A.

The Work under this section is subject to re
quirements of the Contract Documents
including the General Conditions, Supplementary Conditions, and sections under
Division
1
-

General Requirements.

B.

All air handling equipment shall comply with all local, state and federal code
requirements.

C.

In addition,

all air handling equipment shall comply
with Codes, Regulations and
Standards

as listed in Volume 1 of the
UIUC Facilities Standards
.

D.

Additional Codes and Standards as applicable but not limited to:

1.

AABC

Associated Air Balance Council

National Standa
rds,

Ch
-
20, 1989

2.

ACCA

Air Conditioning Contractors of America

ACCA Manual RS

3.

ACGIH

American Conference of Governmental
Industrial Hygienists

Industrial Ventilation, 23
rd

ed. 1998

4.

AMCA

Air Movement and Control Association
International, Inc.

AM
CA Standards 99
-
86,
803
-
96 204; 210; 300; 410

AMCA 99
-
2404;
-
2405;
-
2406;
-
2407;
-
2410

5.

ANSI

American National Standards Institute

ANSI/AMCA 330

ANSI/UL 1136,

6.

ASHRAE

American Society of Heating,
Refrigerating and Air
-
Conditioning
Engineers

ANSI/ASH
RAE
-

68
-
1997;
87.1
-
1992; 120
-
1999

7.

ASME

The American Society of Mechanical
Engineers, International

ANSI/ASME PTC 11
-
1984
(R 95)

8.

ASTM

American Society for Testing and
Materials

ASTM series 400
-

900

9.

ARI

American Refrigeration Institute

ARI 410,
670
-
96,

ANSI/ARI 430

10.

AWS

American Welding Society

ANSI/AWS D9.1
-
90

11.

NADCA

National Air Duct Cleaners Association,
for HVAC & Duct Systems

NADCA Manual

12.

NFPA

National Fire Protection Association

ANSI/NFPA 90A

See note a) below

13.

OSHA

Office

of Safety and Health
Administration

OSHA Standard
-
1910.219

14.

SMACNA

(SMARTA)

Sheet Metal and Air Conditioning
Contractors’ National Association Sheet
Metal And Roofing Contractors Trade
Association of Illinois

SMACNA Series 1980
-
Current editions.

15
.

UL

Underwriters Laboratories Inc.

UL 181


a.

NFPA 90A Latest Revision: All products shall conform to NFPA section 90A,
possessing flame spread rating of not over 25 and smoke developed rating no
higher than 50.

1.05

REFERENCE

A.

The Work under this Section is sub
ject to requirements of the Contact Documents
including the General Conditions, Supplementary Conditions and Sections under Division
1 General Requirements.

1.06

SUBMITTALS

A.

Schedule:

1.

Each fan system schedule shall include, but not be limited to, the following:

a.

Manufacturer's name and model number

b.

Identification as referenced in the documents

c.

Certified Capacities / ratings / test results

d.

Fan curves

e.

Materials of construction and respective gage

f.

Coating process and materials

g.

Independent certified sound power level
s

h.

Fan type, size, class, drive arrangement, discharge/rotation, bearings, drives

i.

Wheel type, diameter, rpm, tip speed

j.

Required fan horsepower including drive losses

k.

Motor data (refer to Division 16)

l.

Vibration isolators furnished with fans

m.

Dimensions and we
ights

n.

Color selection charts where applicable

o.

Manufacturer's installation instructions

p.

Pressure Class.

q.

Support methods including spacing, upper attachments, and lower
attachments.

r.

Sealants and gasketing.

s.

Sealing class.

t.

AHU leakage testing methods, apparatu
s, and apparatus certification signifying
meter is in conformance with ASME requirements for fluid meters.

u.

Include accurately dimensioned drawings with plan, elevation and end views of
the unit being submitted for approval.

v.

Provide any “cut” views so as to

additionally illustrate hidden components not
normally visible from the required views above.

w.

Fan curves shall include a series of curves indicating relationship of flow rate
(cfm) to static or total pressure for various fan speeds, brake horsepower
curve
s, and selection range (surge curves, maximum rpm, etc).

x.

Indicate performance data, based on both design air quantity and 110% of
design air quantity.

y.

For variable air volume application, indicate all operating points on fan curves
including data to indica
te effect of capacity control devices such as Variable
Frequency Drives on flow, pressure and horsepower.

B.

Product Data:

1.

Submit Manufacturer’s technical product data and installation instructions for each:
blower and components including bearings, motor,
drives, flexible connection, all
corrosion protectant, sealant and gasketing material products and accessories.

C.

Product Material Safety Data Sheets:

1.

Include all MSDS, but not limited to those in paragraph B.

D.

Shop Drawings:


1.

Submit shop drawings of all fa
ns for entire facility for approval prior to production.
Drawings shall be to scale showing structural clearances. Drawings shall include
plan, elevation and end views showing all components, with dimensions and
connections. Do not release units for pro
duction prior to response
-

approval of shop
drawings by the Engineer and review by Operations and Maintenance Inspection and
Commissioning team.

1.07

DELIVERY, STORAGE AND HANDLING

A.

Provide All Necessary Means:

for delivery, storage and handling of all related

materials
and components for the fan(s) for related AHU system(s) such that they be kept clean
and void of all miscellaneous construction materials including but not limited to dust, dirt,
fluids, and scrap materials.

PART 2. PRODUCTS

2.01

EQUIPMENT (APPL
IES TO ALL FAN TYPES DESCRIBED IN PART 2)

A.

Tested and Certified:

Fans shall be tested and certified in accordance with applicable
AMCA test codes. All Fans shall be certified AMCA Class II or higher if necessary, per
their application. Units shall arrive

at the Project bearing Certification Seal.

B.

Furnished Complete:

Fans shall be furnished complete with motors, wheels, drive
assemblies, bearings, coating(s) and accessories as hereinafter specified. Motors for V
-
belt drives shall be furnished with adjust
able rails or bases.

C.

Unit Size Ranges: (Fan Type and Class)

1.

“Small” units i.e.) CFM ranging up to 3000 CFM or 6 sq. ft. of associated coil face
area, whichever meets the application criteria first, may utilize “AF” air Foil, “BI”
Backward Inclined or “FC”

Forward Curved, housed DWDI centrifugal fans that are
AMCA Class II.

2.

“Midsize” units i.e.) CFM ranging from 3000 CFM up to 20,000 CFM, or 6 to 40 sq. ft.
of associated coil face area, whichever meets the application criteria first, will be
required to ut
ilize “AF” air Foil or “BI” Backward Inclined, housed DWDI centrifugal
fans that are AMCA Class II.

3.

“Large” units i.e.) as anything beyond 20,000 CFM or beyond 40 sq. ft. of associated
coil face area, whichever meets the application criteria first, will b
e required to utilize
“AF” air Foil or “BI” Backward Inclined, housed DWDI centrifugal fans that are AMCA
Class II.

D.

V
-
Belt Drives:
Furnish fans specified with V
-
belt drives with either variable
-
pitch or fixed
-
pitch sheaves for drives 3 HP and smaller and

fixed
-
pitch sheaves for drives 5 HP and
larger. Select variable pitch sheaves to drive fan at such speed as to produce specified
capacity at approximate midpoint of sheave adjustment.

E.

Fixed
-
Pitched Sheaves:

When fixed
-
pitch sheaves are furnished, system
air balancing
shall be accomplished by trial of different fixed
-
pitch sheaves. This Contractor shall
provide necessary trial and final sheaves and drive belts as required by TAB Contractor.

F.

One Operating Point:

Select fan to operate at single stable opera
ting point as predicted
by fan curve. Any fan having 2 potential operating points on fan curves is not acceptable.

G.

60 To 75 Percent WOCFM:

All fans, constant volume or VAV, shall be selected at
design conditions with the design CFM falling in the range of

at least 60 percent, but no
greater than 75 percent, of Wide Open CFM “WOCFM” for the design rpm. This range
helps avoid the unstable region left of the peak efficiency system curve, which is typically
around 55 percent of WOFCM. This range also avoids
the “top end” of the fan output at
the given static pressure and cfm criteria where noise, longevity concerns and lack of
growth become evident.

B.

Maximum
RPM:
All Fan selections shall conform to all criteria listed in this
Section

15830


Fans
. Additional
ly, the design point RPM for each selection shall be at least 40
percent less than the maximum RPM for the respective fan. AMCA Class selection may
require the next higher class should the above combination of criteria force a new
selection.

C.

Efficiency Cu
rve:

For VAV units or other units compatible with Variable Frequency
Drives, the design operating point shall be at or to the right of the peak efficiency point or
peak efficiency system curve while also complying with Part 2 of the Section. Total
Effici
ency (TE) of the fan selection shall equal or exceed 55 percent at the design point.

D.

Airflow Modulation Devices:

Inlet vanes, variable sliding cutoffs or dampers are not
acceptable for airflow modulation.

E.

All Bearings:

Shall be “Heavy Duty” rated, grea
se lubricated, ball or roller self
-
aligning,
pillow block type housing with grease seal. Bearings shall be selected for a minimum
(AFBMA L
-
10) life of not less than 200,000
-
hrs operation at maximum cataloged operating
speed based on AFBMA 9 and 11. Furni
sh bearings with pressure relief type external
grease fittings. Bearings shall be factory lubricated. Both unit bearings shall have the
same bore, type and manufacturer. At least one of the bearings shall be fixed. The
bearing supports shall be removab
le for access to and removal of the fan wheel.

F.

Centrifugal Fan Shaft Bearings:

In addition to respective fan type bearing criteria,
provide “Lube
-
Lite” or equal auto
-
greasers on all applications in which bearings are
inaccessible due to being platform mo
unted or physically located in a remote location,
which would otherwise require special OSHA regulated access.

G.

Shaft:

Shaft shall be manufactured AISI 1040 or 1045 hot rolled steel shaft, turned,
precision ground and polished steel shafts shall be sized (
and ring gauged for accuracy)
so the first critical speed is at least 25 percent over the maximum operating speed for
each pressure class. Close tolerances shall be maintained where the shaft makes
contact with the bearing.

H.

Belt Driven Fans And Motors:

Unless otherwise indicated, Original Equipment
Manufacturer (OEM) Serial number


matched V
-
belt drive set(s) shall be selected and
provided. Belts shall be applied in matched sets. V
-
belts shall be Gates, Vulco Ropes or
Falk, matched multiple A, B or C
belts having a rating of not less than 150 percent of the
motor nameplate horsepower. (Multi
-
groove pulleys using 2, 3 or 4 grooves shall be
provided with matching companion pulleys such that the belts are properly aligned).
Motors shall have slide rails

for belt tension adjustment and variable
-
pitch (up through 3
hp) or fixed
-
pitch cast iron sheaves. Only fixed sheaves rated at 150 percent service
factor shall be used on systems using motors larger than 3 hp. Supplier shall agree to
fully exchange 1 dr
ive set during final commissioning (balancing) at no additional expense
to the University. The drive set shall use a minimum of 2 belts up to a maximum of 4
belts.

I.

OSHA Approved Drive Assembly Housings:

Use only OSHA approved drive assembly
housings or
guards as per standard 1910.219 or current standard during award of
Contract. Each motor and drive shall have an OHSA approved guard arranged to permit
easy removal for replacement of belts. Guards shall be rigidly installed to prevent noise
from vibrati
on and shall have 3
-
inch diameter hole with finished collar opposite fan shaft for
use in taking fan rpm readings without removing the guard.

J.

Coatings:

Applications requiring coatings or potentially require coatings shall be
coordinated and approved with

the Project Engineer and Engineering Services within the
Operations and Maintenance Division of the University of Illinois, Champaign, Illinois.

1.

Generally, any exhaust application that may be in contact with acids, alkalis,
oxidizing agents, salts, solv
ents, abrasive elements, certain gaseous compounds,
chloride based compounds, combustible carbon based molecules, animal oils, other
off gases, and saturated steam. While some coatings are good to excellent against
some if not all relevant University base
d applications; sunlight may deteriorate or
oxidize some coatings resulting in possibly shortened life than planned.

2.

A partial listing of coatings shown below shall be considered first when determining
which product may be best against the particular exhau
st components.

3.

High
-
Pro Polyester, Epoxy, Greenkote
TM
, Greenkote
TM

Plus, Baked Phenolic, Epoxy
Phenolic, Vinylidene Fluoride

4.

Generally, zinc rich paint is not recommended as a protective coating against most
acids, alkalis, oxidizing agents, salts, solven
ts, certain gaseous compounds,
chloride based compounds, combustible carbon based molecules, animal oils, and
other off gases.

5.

Required surface preparation will vary depending on the appropriate coating for the
application. Levels of preparation range fro
m SSPC
-
SP1 through SSPC
-
SP10. Fan
manufacturer shall be responsible for proper preparation and coating based on the
Project application requirements as described in this Section and/or shown on the
Schedule.

K.

Balancing Fan and Drive Assemblies:


1.

Use the mo
re stringent vibration tolerance specified in this
Section 15830


Fans,
Section 15720


Air Handling Units
, and
Section 15070


Mechanical Sound,
Vibration, and Seismic Control
.

2.

Unless otherwise stated in this
Section 15830
-

Fans
, each fan
\

wheel shall
be
statically and dynamically balanced to grade G6.3 per ANSI S2.19. Complete fan
assembly shall be factory balanced statically and dynamically in accordance with
AMCA Standard 204.

3.

Each fan assembly shall be test run at the factory at the specified fan R
PM and
vibration signatures shall be taken on each bearing in three planes; horizontal,
vertical, and axial. The maximum allowable fan vibration shall be the lower of either
that stated under this Article 2.01
-

Equipment or 0.110 in./sec peak velocity, fi
lter
-
out reading as measured at the fan RPM. This report shall be provided concurrently
with the unit shipment and at no charge to the Owner.

4.

Fans incorporating variable frequency drives shall be balanced for inverter duty
operation. The fan shall be bal
anced over the entire range of fan operation i.e. 30
percent to 100 percent of design operation.

5.

Filter
-
in measurement (all fan assemblies) shall be taken in the horizontal and
vertical planes on the drive and opposite
-
drive sides of the fan shaft.

a.

Fans
not using variable frequency drives
-

Measurements shall not exceed
0.0785 inches/sec peak to peak in any plane.

b.

Fans using variable frequency drives
-

Measurements shall not exceed 2.0 mils
in any plane at or below 750 rpm and shall not exceed .0785 inc
hes/sec in any
plane beyond 750 rpm for inverter duty fans.

6.

Filter
-
out measurements (all fan assemblies) shall be taken in the horizontal, vertical
and axial planes on the drive and opposite
-
drive sides of the fan shaft.

a.

Fans not using variable frequency

drives
-

Measurements shall not exceed
0.110 inches/sec in any plane.

b.

Fans using variable frequency drives
-

Measurements shall not exceed 2.8 mils
in any plane at or below 750 rpm and shall not exceed .110 inches/sec in any
plane beyond 750 rpm for inv
erter duty fans.

7.

The above criteria shall also apply to field replacement fan(s) and their drive
assemblies. These units, in addition to being factory balanced, shall receive a final
balance using the same criteria after being installed in the existing ai
r moving
system.

8.

Factory and Final balance reports shall be provided and at no cost to the Owner.

L.

OSHA Compliant Belt Guards:

Provide OSHA compliant belt and shaft guards to
enclose entire drive. Construct face of guards of expanded metal having minimum

60%
free area to allow for ventilation; provide speed test openings at shaft locations.

M.

Sound Power Levels:

Shall be based on tests performed in accordance with AMCA
Standards 300 and 301 and shall not exceed the lower of that listed by AMCA or as
other
wise specified on the Drawings.

N.

110% Air Quantity Scheduled:

Each fan and motor combination shall be capable of
delivering 110% of air quantity scheduled at scheduled static pressure. Motor furnished
with fan shall not operate into motor service factor i
n any of these cases.

O.

Drive Efficiency:

Consider drive efficiency in motor selection according to manufacturer's
published recommendation, or according to AMCA Publication 203, Appendix L.

P.

Lateral Restraint Type Isolation:

Provide lateral restraint type
isolation separate or
integral to the general fan assembly
-

internal isolation for systems with angular or
horizontal discharge arrangements. Selection shall prevent lateral thrust and movement
that could damage any associated air delivery component i.e.

fan, fan assembly, flex
connection, framing, motor assembly etc.

Q.

Ductwork Changes:

Where inlet and outlet ductwork at any fan is changed from that
shown on drawings, submit scaled layout of change and system effect factor calculations
indicating increase
d static pressure requirements as described in AMCA Publication 201.
This Contractor shall be responsible for costs associated with any motor; drive and / or
wiring changes required as a result of duct configuration changes at fan.

2.02

CENTRIFUGAL FANS

A.

General
:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.

B.

Fan Housings:

Use heavy gage steel, continuously welded throughou
t at minimum on all
“BI” and “AF” units, braced and supported by structural channels or angle irons to prevent
vibration or pulsation, flanged outlet, fully streamlined inlet. Housings with lock seams or
partially welded seams are not acceptable on all BI

and AF units.

C.

Wheels:

In conjunction with Article 2.01, backward inclined or non
-
overloading airfoil
blades fully welded to spun wheel cones as indicated on schedules. Backward incline
wheels shall be single thickness plate type continuously welded to t
he rim and back
plate. Partial welding on back plate will not be acceptable. BAF airfoil wheels shall be
die
-
formed airfoil blade type, continuously welded to the rim and back plate. Partial
welding will not be accepted on airfoil blades. Smaller sized

units may use extruded
aluminum blades. All BI and BAF fan wheels shall be statically and dynamically
balanced as defined earlier in this Section.

D.

Painting:

All metal parts shall be painted with prime coat after metal cleaning and
surface preparation.
In addition, apply second coat of paint to all exterior surfaces.

E.

Mounting Rails:

Furnish common mounting rails for fan and motor as appropriate for fan
arrangement indicated.

F.

Inlet Screens:

Minimum 16 gage galvanized, 1
-
inch wire mesh for fans without
inlet
ductwork as required.

G.

Access Doors:

Bolted and gasketed type in fan Housing for inspection of interiors and
wheel.

H.

Drain Connection:

1 inch NPT external threads located at the lowest point of Housing
as required.

2.03

PLENUM / PLUG FANS

A.

General:
All re
lated criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.

B.

Configuration:
Fans shall be airfoil centrifugal type designed for industri
al duty and
suitable for continuous operation. Fans shall be single width, single inlet arrangement
plenum fans with capacities and operating characteristics as indicated on schedules. All
criteria listed in Article 2.01 shall apply. Minimum clearance s
pacing for efficient air entry
and exit shall be in accordance with AMCA and any additional Section criteria in order to
minimizing airflow deratings, noise generation and general efficiency losses.

C.

Hubs:

Hubs shall be welded fabricated hubs with straight

bores and keyways. Hubs
shall be screwed to the shaft with a minimum of 2 set screws for positive attachment.
Hubs using taper lock bushings are not acceptable.

D.

Wheels:

Backward incline airfoil type blade, double skinned and welded to center and
wheel s
ide
-
plates. Fan impeller diameters shall conform to AMCA Standard 99
-
2401
-
82.
Fan blades shall be designed to provide smooth airflow over all surfaces of blade. Smaller
sizes shall have solid airfoil
-
shaped hollow air foil blades. Fan shafts shall be so
lid AISI
C
-
1040 or 1045 hot rolled steel. Straight shafts shall be turned, ground and polished to a
minimum 16 micro
-
inch finish. Shaft shall be sized to run at a minimum of 20% greater
than the maximum AMCA class speed.

E.

Bearings:

Use ‘Lube
-
Lite’ auto l
ubrication systems or equal when extended lube lines
are necessary.

F.

Screen Enclosure:

Entire plug fan and drive assembly shall be encased with protective
screen enclosure. Enclosure shall be constructed of aluminum or galvanized steel mesh
or expanded me
tal and sized to have no measurable system effect on fan performance.
Screen shall be reinforced as required to maintain stable structure during fan operation.
Access shall be provided.

G.

Access Door:

Access door shall be of suitable size to allow service

personnel into
enclosure for periodic service.

H.

Disassembly:

When required, enclosure shall be designed and constructed to allow for
complete disassembly. Refer to
Section 15720
-

Air Handling Units

for additional
information regarding component size re
strictions so as to fit through doorways.

I.

Inlet Screens:

Shall use heavy gage, corrosion resistant, zinc plated steel wire for fans
without inlet ductwork.

J.

Inlet Cones:

Inlet cones shall be precision spun. Inlet cones shall be aerodynamically
matched
to wheel side plate to insure full loading of blades. Inlet cones shall be heavy
gage steel.

K.

Painting:

All metal parts shall be painted with prime coat after metal cleaning and
preparation of surface. In addition, apply second coat of paint to all exteri
or surfaces.

2.04

TUBULAR CENTRIFUGAL FANS

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this article should a conflict
arise.

B.

Housings:

Heavy gage

and continuously welded steel fabrication, adequate reinforcing to
prevent housing distortion, fully streamlined inlet cones, multiple straightening vanes
following fan wheel to redirect air flow to minimize noise and reduce turbulence and
flanged inlet a
nd outlet. Fan Housings shall be designed to promote straight
-
line airflow
from entrance to discharge.

C.

Wheels:

Non
-
overloading airfoil or backward inclined blades welded to wheel cones as
indicated on schedules. Typical wheel sizes up to 15 inches may u
se single plate
design. Larger sizes shall have airfoil blades. Blades shall be continuously welded to
back plate and wheel cone. Partial welding is not acceptable.

D.

Bearings:

Drives and bearings shall be contained within belt tube, isolating drives
c
ompletely away from airstream. Extend grease lines to outside of housing using ‘Lube
-
Lite’ auto lubrication systems or equal.

E.

Painting:

Fan parts shall be painted with prime coat after metal cleaning and surface
preparation. In addition, apply second co
at of paint to exterior surfaces.

F.

Motor Mounting:

Fan motor shall be mounted on adjustable platform.

2.05

MIXED FLOW FANS: AXIAL/CENTRIFUGAL HYBRID

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the follo
wing components. Use the specific criteria in this article should a conflict
arise.

B.

Housing:

Heavy gage/steel with welded construction. Housing shall have inlet and outlet
collars for slip fit duct connections. The housing and bearing support shall be
constructed
of structural steel members to prevent vibration and rigidly support the shaft and bearings.
Welded steel vanes shall straighten the flow of air from the fan discharge and support
bearings and drives.

C.

Wheels:

Mixed flow type with welded wheel

cone, spherical back plate and single
thickness cambered blades. Wheels shall be statistically and dynamically balanced to
balance grade G6.3 per ANSI S2.19. The wheel cone and fan inlet cone shall be carefully
matched and shall have precise running tol
erances for maximum performance and
operating efficiency.

D.

Bearings:

Drives and bearings shall be contained within belt tube, isolating drives
completely away from airstream. Use ‘Lube
-
Lite’ auto lubrication systems or equal with
extended lube lines where

necessary.

E.

Painting:

Fan parts shall be painted with prime coat after metal cleaning and surface
preparation. In addition, apply second coat of paint to exterior surfaces.

F.

Motor Mounting:

Fan motor shall be mounted on an adjustable platform appropriate
for
the fan arrangement.

2.06

AXIAL FANS

A.

General:

All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this article should a conflict
arise for Tubular and/or Vane
type Axial Fans.

B.

Tube Axial Fans

1.

Variable Pitch
-

Tube Axial

type fans are prohibited.

2.

Housing:

using hot rolled steel with continuously welded steel drum and rolled steel
flanges shall be required.

3.

Wheel:

Die formed with welded construction or cast alumi
num airfoil design. Shall
be statically and dynamically balanced to ANSI S2.19, G6.3. Final vibration
readings shall not exceed the lower of either
Article 2.01
-

Equipment

or 0.1inches
per second at the shaft speed.

4.

Bearings:

Use ‘Lube
-
Lite’ auto lubric
ation systems or equal with extended lube
lines.

5.

Inspection Panel:

Easy access panel required for service of internal components of
unit.

6.

OSHA Belt Guard:

Required on belt drive units.

7.

Motor:

Motors and drives shall be scheduled on Drawings. Design req
uirements will
determine if unit is direct drive or belt drive.

C.

Vane Axial Fans:

1.

Variable Pitch Type:

Usage of variable pitch vane axial fans is prohibited.

2.

Housing:

using hot rolled steel with continuously welded steel drum and rolled st
eel
flanges shall be required.

3.

Straightening Vanes:

Heavy gage steel construction fixed inlet guide vanes welded
in the casing on the inlet bell.

1.

Wheel:

Die formed with welded construction or cast aluminum airfoil design. Shall
be statically and dynamical
ly balanced to ANSI S2.19, G6.3. Final vibration
readings shall not exceed the lower of either
Article 2.01
-

Equipment

or 0.1 inches
per second at the shaft speed.

2.

Bearings:

Use ‘Lube
-
Lite’ auto lubrication systems or equal with extended lube
lines.

4.

In
spection Panel:

Easy access panel required for service of internal components of
unit.

5.

OSHA Belt Guard:

Required on belt drive units.

6.

Motor:

Motors and drives shall be scheduled on Drawings. Design requirements will
determine if unit is direct drive or
belt drive.

2.07

VENTILATION SETS (TOILET AND GENERAL EXHAUST FANS)

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this article should a conflict
ar
ise.

B.

Housing:

Continuous welded heavy gage steel housing. Class 1 or 2 construction as
required by design.

C.

Wheel:

Backward incline wheel shall be single thickness plate type continuously welded
to the rim and back plate. Partial welding on back plate w
ill not be acceptable.

D.

OSHA Belt Guard:

OSHA Belt guard or weather hood cover required for protection from
rotational parts of unit.

E.

Motors:

Motors and drives shall be scheduled on the Drawings.

2.08

HOOD EXHAUST FANS

A.

General:
All related criteria listed in A
rticle 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this article should a conflict
arise.

B.

Housing:

Continuous welded heavy gage steel housing with 1
-
inch drain connection.
Class 2
-
constructi
on minimum.

C.

Wheel:

Backward incline wheels shall be single thickness plate type continuously
welded to the rim and back plate. Partial welding on back plate will not be acceptable.
Single width and single inlet design shall be used. Special exhaust sys
tems could
require non
-
sparking wheels. Contact Operations and Maintenance, Engineering
Services.

D.

Shaft:

Shaft seals are required. Additionally, 316L material for shafts is acceptable and
may be required under certain applications. Verify requirement w
ith the Project Engineer.

E.

OSHA Belt Guard:

OSHA belt guards or weather hood cover required for protection from
rotational parts of unit.

F.

Motors:

Motors and drives shall be as scheduled on the Drawings.

G.

Coatings:

Chemical resistant coatings are required on

fan wheel and contact air surface
areas as per design of usage of equipment. Typical regular wet lab applications shall use
Epoxy or baked phenolic coatings unless alternative product(s) and/or process(es) are
certified equal or better as tested and compa
red by an independent nationally recognized
testing agency. Consult Operations and Maintenance, Engineering Services for other
special applications.

H.

General Note:

Multiple chemical fume hood installations could require specialized types
of fume hood exhau
st fans. Consult Operations and Maintenance Engineering Services for
final approval.

2.09

VENTILATING SET, GENERAL PURPOSE

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the
specific criteria in this Article should a conflict
arise.

B.

Class 1 Rated
: The vent set shall be certified AMCA Class 1 at minimum. A “utility vent
set” is not acceptable.

C.

Fan Housing:
The entire fan housing shall be of continuous welded steel constructi
on.
Crimped or spot welded construction is not acceptable. The fan housing shall be oriented
so as to facilitate the installation requirements addressed below in Paragraph 3.05.

D.

Fan Wheel:

The fan wheel shall be of the
airfoil or backward inclined type

and shall be of
continuous welded steel construction.

E.

Bearings:

Each bearing shall be of the relubricable pillow block type with an AFMBMA

L
-
10 rating of 200,000 hours, minimum.

F.

Motor:

The electric motor shall comply with the requirements of
Section 1622
0
-

Motors.

G.

Vibration Isolators:

The vent set shall incorporate 1
-
inch or 2
-
inch deflection “restrained
spring” or “rubber and spring” type vibration isolators as appropriate, each of which is
individually sized for the portion of the total unit weight pl
us any additional loading that it is

required to support during operation (with consideration given to the specific motor being
utilized).

H.

Indoor/Outdoor Applications:

In outdoor applications each vent set shall incorporate an
easily removable weather cov
er and may be “Arrangement 10” (i.e. motor located inside
base) to accommodate such a cover. In indoor applications each vent set shall
incorporate easily removable OSHA shaft and belt guards with provision for taking RPM
measurements without the necessi
ty of guard removal.
Each indoor application shall be
other than Arrangement 10, to maximize ease of access. A weather cover is not
acceptable on an outdoor application attempting to use indoor equipment.

I.

Performance:

1.

Sizing/Selection:

The fan shall be
sized/selected on the basis of
maximizing
operating efficiency

(while maintaining an appropriate “safe distance” from unstable
operation)
even though this typically results in the selection of a larger, more
expensive unit

that is minimally required to ach
ieve the required performance.

2.10

VENTILATING SET, SPECIAL PURPOSE

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
ar
ise.

B.

Compliance / Modifications:

Each special purpose vent set shall comply with the
requirements of
Article 2.09
-

Ventilating Set, General Purpose

except as modified for the
specific applications addressed below.

C.

Laboratory / Corrosive Exhaust

1.

Fan Housi
ng:

The fan housing shall incorporate a threaded drain connection (that is
located at the bottom of the housing after it has been rotated into its final position)
and an access/clean
-
out door.

2.

Fan Wheel:

The fan wheel shall be of the backward inclined ty
pe only. An airfoil
type wheel is not acceptable.

3.

Protective Coating:

All surfaces of the fan housing, wheel and shaft that are
exposed to the corrosive airstream shall be protected with an appropriate coating. In
an acidic fume exhaust application a
ba
ked

phenolic or epoxy coating shall be
utilized.

4.

Corrosion Resistant Materials:

In extremely corrosive applications (nonstandard),
the fan housing, wheel and shaft (as required) shall be constructed of an appropriate
inherently corrosion resistant materia
l that requires no protective coating (e.g.
polypropylene, fiberglass, stainless steel, etc.).

D.

Explosion Proof

1.

Special Materials/Design:
Special nonferrous materials of construction and vent
set design features shall be incorporated to achieve the necessa
ry explosion proof
rating as required for the application.

2.11

PROPELLER EXHAUST FANS

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article sh
ould a conflict
arise.

B.

Propeller:

Heavy duty, welded, reinforced steel blades or heavy duty cast aluminum
blades. Keyed hubs required. NOTE: Small propeller fans can have different
specifications for blades and hubs. Contact O&M Variance Committee.

C.

Mot
or:

Motors and drives shall be scheduled on the Drawings. On belt drive units;
motors shall be mounted on an adjustable motor base. Motor shall be equipped with an
adjustable pitch sheave.

D.

Frame:

One piece, square steel with die formed venturi orifice,

mounting flanges and
supports, with baked enamel finish. Welded construction.

E.

Safety Screens:

Expanded galvanized metal over inlet, motor, and drive [and outlet]
shall comply with OSHA regulations.

2.12

ROOF AND WALL MOUNTED EXHAUST FANS

A.

General:
All relate
d criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.

B.

Types:

Up blast and down blast. Spun aluminum exhaust fans with centrifugal ba
ckward
inclined blade. Wheel cones matched to the venturi for maximum efficiency. Wheels shall

be statically and dynamically balanced.

C.

Motors:

Motors and drives shall be scheduled on the Drawings.

D.

Disconnect Switch:

Factory wired non
-
fusible in housing
for thermal overload protected
motor. Direct drive units also require a wall mounted multiple speed switch or solid
-
state
speed controller.

E.

Motorized Damper:

Motorized opposed blade damper interlocked with fan
. See Section
15820


Duct Accessories
for d
amper requirements.

F.

V
-
Belt Drive:

Cast iron or steel sheaves, dynamically balanced, bored to fit shafts and
keyed, variable and adjustable pitch motor sheave selected so required rpm is obtained
with sheaves set at mid
-
position.


G.

Screens:

Aluminum rigid
wire bird screens are required.

H.

Roof Curb:

12 inches minimum curb height with continuously welded seams, built in
cant strip or field installed cricket, 1 inch insulation, and installed wood nailer strip.

I.

Wall Mount:

Factory fabricated wall
-
mounting plat
e shall be provided.

J.

Kitchen Hood Exhaust:

Kitchen hood exhaust system fans are required to have non
stick wheel coating, hinge kit, clean out ports, bird screen, drain connection, grease trap,
heat shield baffle, and vented curb extension as code require
s. Dampers are not required
for this type of installation.

2.13

INLINE CABINET FANS (FOR REMOTE TOILET OR GENERAL EXHAUST APPLICATIONS)

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following compone
nts. Use the specific criteria in this Article should a conflict
arise.

B.

Centrifugal Fan:

V
-
Belt or Direct driven fan wheel shall be backward incline, aluminum,
with matched wheel cone. Wheels and fan assembly shall be statically and dynamically
balanced

as per Article 2.01

C.

Housing:

Rigid formed structural members and formed galvanized steel panels.

D.

Disconnect Switch:

Factory wired non
-
fusible in housing for thermal overload protected
motor wall mounted multiple speed switch or solid
-
state speed control
ler.

E.

Belt Drive:

Cast iron or steel sheaves, dynamically balanced, bored to fit shafts and
keyed, variable and adjustable pitch motor sheave selected such that required rpm is
obtained with sheaves set at mid
-
position, fan shaft with self aligning pre
-
lub
ricated ball
bearings.

2.14

UNIT BASE AND FRAME (AS APPLICABLE)

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.


B.

Structural Steel Members:

Each unit may have either continuous length base structural
steel members or each section shall incorporate structural steel members. All related
welding shall be per AWS D1.1 standards. If galvanized structures are used, wel
ded
seams shall be properly cleaned and painted with zinc rich coating.

C.

Sections Shipped Separately:

If sections are to be shipped either knocked down and
\

or separately so as to fit through 34
-
1/2 inch by 84 inch door openings then the base and
frame ad
joining seams shall integrally fit and be able to be securely fastened without
allowing sagging or bowing. Bids will be required to clearly specify if field welding is
required.

D.

Lifting:

Each unit shall incorporate lifting lugs and forklift channeled slo
ts in base rails
that are suitable for rigging without requiring additional support frames or rails. Unit base
rails shall have at minimum enough rigidity so as to be able to be lifted using either
method without permanent deformation to the housing, base

or internal components.
Lifting diagrams shall be provided with each shipped unit and separately shipped section.

2.15


UNIT HOUSING (AS APPLICABLE):

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the fo
llowing components. Use the specific criteria in this Article should a conflict
arise.

B.

Gage:

Use sufficient gage of galvanized steel ASTM 525 UL G90 finish on each
panelized section so as not to deflect more than 1 / 200th of the span under design
workin
g pressure. In any case, exterior shall not use any lighter gage weight less than 16
gage galvanized steel ASTM 525 UL G90 finish.

C.

Welded:

Housing shall be continuous seam welded. Units with welds on exterior
surfaces or welds that have burned through f
rom interior welds shall also receive a final
shop coat of zinc
-
rich protective paint in manufacturer's standard color (if painted), or
provide galvanized frame construction with bolted frame connections.

D.

External Motor:

If unit is provided with an exte
rnal motor, unit shall include a belt guard
over drive components.

E.

Fit Through Door Opening:

For replacement
\

remodel applications as necessary,
each section (fan) shall be constructed so as to fit through a 34
-
1/2 inch wide by 84 inch
high door opening

or be of a knockdown construction packed and shipped as such for re
-
assembly at the destination. Instructions and tagging of each component for easy field
match
-
up, sufficient and appropriate gasketing and fasteners shall be included.

2.16

BLOWER SECTION

A.

Gene
ral:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.

B.

Sufficient Space:

Allow sufficient space between fan inlet co
nes and the nearest
internal unit housing wall allowing for obstructions and air density corrections so as to
have less than 0.1 in. w. g. “system effect factor” as Illustrated in
AMCA Publication 201
Fans and Systems

as an adder to the system static. As
a minimum, use the equivalent
of either:

1.

(3) Inlet cone diameters as a guideline,

2.

Or the equivalent full width of fan wheel as a guideline.

C.

Fan Performance:

Shall be based on tests made in accordance with current AMCA 210
standards and comply with the req
uirements of AMCA certified rating program for air and
sound. All forward curved and airfoil wheel(s) shall comply with AMCA standards
including but not limited to those listed in
Article 1.04

above.

D.

Fan Class:

The minimum fan class shall be “II” for t
he optimum diameter needed unless
otherwise specified in the Drawing Schedule.

E.

DWDI FC, BAF or BI Type:

Refer to Article 2.01 Equipment for ranges of sizes
accepting specific type(s) of wheel designs i.e.) forward curve (FC) and / or backward
inclined (BI
) and / or backward inclined
-

airfoil (AF). The respective housing shall be
designed and constructed using a heavy
-

gage continuous
-

welded (BI or AF units) and
continuous lock seam (FC) blower Housing so as to not “oil can” i.e.) not deflect under
any

operating range in its approved class for this application. Use “draw through”
-

Centrifugal DWDI type assemblies unless otherwise specifically pre
-
approved in writing for
acceptance of an alternate (type of fan and / or configuration) from Engineering S
ervices,
University of Illinois Operation and Maintenance Division.

F.

Fan Discharge:

shall be as per the Schedule / Drawing(s) and abiding with AMCA
recognized arrangements for the blower section.

G.

A Flexible Boot Connection
: shall be used between the fan

discharge outlet and the
unit housing. It shall withstand 10 inches w. g. of static pressure without ripping or
leaking in excess of the previously stated unit leakage guidelines.

H.

Internal Spring Type Isolators:

with 2
-
inch deflection range shall be us
ed to isolate the
centrifugal type fan and motor drive base assembly. The assemblies shall be sized such
that the springs will not flex beyond their respective midpoints under static loaded weight.
(If unit requires external isolation, the Contractor shal
l be responsible for isolating the
entire unit including the ductwork and piping at the manufacturer's specified load points).
All isolators shall be free standing, un
-
housed, and use laterally stable spring steel.
Springs shall be assembled into an uppe
r load plate and leveling assembly and into a
lower load plate with a molded neoprene bottom plate assembly. See also Vibration
Isolation in this Section.

I.

Drive Assembly and Door Location:

Drive assembly and drive side access door
location shall be desig
nated as “air hits the back of your head”.

J.

Blower Section:
shall have heavy gage metal hinges and latches on access doors.
Refer to unit housing section for additional requirements. Incorporate 1 door each for left
and right hand sides of section. Wit
hin the acceptable size range, forward curved units
shall provide their standard and standard option access door(s)

K.

Air Leakage:

Unit or section air leakage shall not exceed 1 percent of the design airflow
or the SMACNA leakage class 6, each as follows:

a.

1 percent of the design airflow in CFM

b.

F = C x P ^ 0.65. Where F = CFM leakage per sq. Ft. of Housing Area and



C = 6, P = Design Static in w. g.,

c.

L = F x A. Where L = total leakage CFM, F from above and A = housing area sq. ft.
and shall include

all sections of AHU.

2.

Fit Through Door Opening:

For replacement or remodel applications, and after
factory test


balancing; each fan housing (and the fan assembly if necessary) shall
be disassembled and packed for shipping so as to be able to fit compon
ents through
34
-
1/2 inch wide by 84 inch high opening (otherwise, use specific dimensions when
shown on Drawings). Provide instructions and tagging of each component for easy
field match
-
up, sufficient and appropriate gasketing and fasteners shall be incl
uded.

2.17

DRAIN PAN

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.

B.

Fan Replacements:

Provide a drain pan any
time a fan replacement application
illustrates historical potential for water to be in the fan section regardless of other
corrective measures. Coordinate this requirement with the Section Floor requirement.
Refer to
Section 15720


Air Handling Units

fo
r criteria.

2.18

SECTION FLOOR

A.

General:
All related criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.

B.

Framing:

Provide a floor and su
pport framing, per fan manufacturer’s recommendations if
not already as designed and shown on the Drawings.

C.

Refer to
Section 15720


Air Handling Units

for additional criteria.

2.19

ELECTRIC MOTOR

A.

Additional Criteria:

Unless otherwise stated here in
Section 1
5830

and
\

or in the
Drawings, see also
Division 16

and notably
Sections 16220



Motors
, and
16260



Static
Power Converters (VFD requirements)

for additional criteria.

B.

Open Drip
-
Proof:

is acceptable except where specifically noted otherwise.

C.

VFD Compatib
le:

Motors shall be designed for 1750 rpm and VFD or Inverter approved.

D.

Factory Mounted:

Blower section fan motor shall be factory mounted on an adjustable
base with sheaves and belts factory tested.
If necessary
, factory design, build, test and
balanc
e, then disassemble and crate for shipping so as to fit through a 34
-
1/2 inch wide
by 84 inch high door opening or other dimensions
when and as

described on the
Drawings.

2.20

PRESSURE CLASS

A.

VAV:

For coordination purposes, unless otherwise indicated, the press
ure class for VAV
system ductwork upstream of the air terminal devices shall be equal to or greater than the
static pressure at the fan outlet but not less than 4 inches w.g. for the discharge side
ductwork.

B.

Constant Volume:

For coordination purposes, unl
ess otherwise indicated, pressure
class for Constant Volume system ductwork shall be equal to the external static pressure
(fan outlet or discharge pressure minus associated unit internal component pressure
drop.)

2.21


VIBRATION ISOLATION

A.

General:
All related

criteria listed in Article 2.01 shall apply unless in conflict specifically
with the following components. Use the specific criteria in this Article should a conflict
arise.

B.

Isolators:

A platform style galvanized angle iron frame using rubber/spring ty
pe deflection
isolation springs each having a 1
-
inch vertical deflection range shall support all internally
isolated fan(s) up to 5,000 CFM. All other units, depending on the application, require 2
-
inch vertical deflection or unless a formal written appro
val has been granted by the
Operations and Maintenance Review committee. This subsequent approval would be in
response to a formal written variance request. Isolators shall be securely fastened to the
building
\

fan section structure and the opposite en
ds of the isolators securely fastened to
the fan frame
\

platform.

1.

Sizing of the respective isolators shall be as per the Schedule if not specified by the
fan
\

air
-
handling manufacturer. Any field
-
engineered isolation
\

support system
needs written pre
-
approval from the project engineer and Operations and
Maintenance Engineering Services group.

2.

Horizontal isolators and
\

or lateral restraints may be required and provided in like
manner as for the vertical isolators.

C.

Additional Criteria:

Unless otherwis
e stated here in Section 15830, see also
Section
15720


Air Handling Units

and
\

or the Drawings.

2.22

FLEX CONNECTIONS

A.

Additional Criteria:

Unless otherwise stated here in
Section 15830
, see also
Section
15720


Air Handling

Units, Section 15820
-

Duct Acces
sories

and
\

or the Drawings.

B.

Connections:

Between inlet and discharge openings of fans and ducts shall be made
with a section of at least 1/16
-
inch thick neoprene coated fiberglass fabric. Flexible
connections shall not be less than 4 inches long and sh
all have at least a 1
-
inch slack.
Connections shall have angle frames at each end for rectangular ducts, and metal tension
bands for round ducts. Flexible connections shall be installed to allow easy replacement
and shall be installed on straight duct sec
tions, not on transitional fittings or tapers.

C.

External:

Duct
-
to
-
unit flexible connections are not required on supply and return fans
that are internally isolated in housings or plenums.

D.

Flexible Boot Connections:

Each flexible boot connection shall with
stand 10 inches w.
g. of static pressure without ripping or leaking in excess of the previously stated Unit
leakage guidelines.

2.23

GALVANIZED STEEL SHEET

A.

G90:

First quality, lock former quality (LFQ), cold rolled, open hearth soft steel sheet
capable of doub
le seaming without fracture, ASTM A924 (formerly ASTM A525) or ASTM
A653 (Formerly ASTM A527). Galvanized coating shall be G90. G90 means the total
amount of zinc on both sides is 0.90
-
oz/sq. ft. (0.45 oz/sq. ft. per side).

B.

Painting:

Use G90 Galvaneal o
r Zincgrip where painting is specified.

2.24

UNIT SEALANT AND GASKETING

A.

Sealant:

1.

UL Classified sealant as compounded specifically for sealing joint and seam in
ductwork. Acceptable manufacturers are Hardcast, United McGill, Mon
-
Eco
Industries or H. B. Fuller/F
oster.

2.

Duct tapes are not allowed.

3.

Select sealant as recommended by manufacturer for specific application.

4.

Submit sealant manufacturer’s data sheets including performance data, pressure
ratings, surface burning characteristics data, and manufacturer’s deta
iled installation
instructions.

B.

Gaskets:

1.

Butyl or polymer based tape similar to Ductmate 440, Ventfabrics Ventlok No. 797 or
799 in flanged joints.

2.

Gasket material shall be FDA or USDA approved.

2.25

ACOUSTICAL ENCLOSURE

A.

Enclosure:

Inner layer shall be a 2 inc
h thick minimum layer of 3 psf glass or mineral
fiber similar to type R insulation where specified in
Division 15

for wall construction. Outer

layer shall consist of 2 layers of 5/8 inch thick sheet rock with staggered seams, attached

to sheet metal studs

which are attached to structure not ductwork.


PART 3. EXECUTION

3.01

SOURCE QUALITY CONTR
OL

A.

Responsibility:

Installing Contractor shall be responsible for finishes, ensuring they are
per approved specifications. Only minor superficial repairs will be con
ditionally approved
by the A/E. Relevant replacement of rejected component(s) shall be required.
Components shall not be altered to appear as other than their respective original design
and manufacture as approved by the Project Engineer.

B.

Responsibility:

Installing Contractor shall be responsible for verifying finishes for received
materials, ensuring finishes are per approved specifications and have not been altered to
appear as other than their respective original design and manufacture as approved by
the
Project Engineer.

C.

Damage or Defects:

All steel and sheet metal for purposes including but not limited to
framing and surfaces shall be free of kinks, dents, scratches, stains etc. and shall not
exhibit an absence of proper galvanizing before and after

assembly.

D.

Cleaning:

Properly clean all components internally and externally prior to assembly
should they be found in any other condition than like new and clean condition.

3.02

FIELD QUALITY CONTRO
L

A.

Inspection And Resolution:

Periodically during constructio
n and commissioning the
design Engineer and UIUC O&M Inspection Team may at their discretion review and
inspect the Project Work. Those under Contract shall provide immediate resolution
whenever products or Work including craftsmanship are not in complianc
e with the
Contract Documents.

3.03

PROTECTION

A.

Coordination:

Confer with O&M Inspection Team for desired temporary duct alterations,
filtering and final hookups.

B.

Temporary Protection:

All ductwork shall be protected with fabricated end caps for “end
of the
day” runs to prevent dirt or moisture contamination of system during construction.

C.

Precaution:

Use all reasonable precautions to prevent duct materials from becoming
dirty, oily or damaged prior to fabrication and thereafter during construction and any
re
installation(s). This is to minimize extent of repair, replacement, and subsequent
additional cleaning.

D.

Protection:

All air handling equipment shall be protected with fabricated end caps for
“end of the day” runs to prevent dirt or moisture contamination

of the unit(s) until ductwork
is permanently attached.

3.04

CONSTRUCTION

A.

Craftsmanship:

Construct connecting ductwork so that interior surfaces are smooth.
Internal duct hangers and internal bracing are not allowed. Internal tie rods are not
allowed except

for duct 97 inches and larger through positive 6
-
inch w.g. class. Tie rods
shall be galvanized steel with a minimum 3/8
-
inch diameter.

B.

Transitions:

Provide transitions where different size or different shape ductwork
segments are connected. Unless othe
rwise approved in writing from Engineering Services
Operations and Maintenance Div. in response to a formal variance request, make diverging

transitions with a maximum angle of 15 degrees per side (or 30 degrees total diverging)
and 25 degrees per side for

converging transitions (or 50 degrees total converging).

3.05

INSTALLATION

A.

Support Requirements:

Refer to
Section 15060


Hangers and Supports

for additional
support requirements including attachments to structures. All unit section(s) shall be
installed le
vel (in the same dimensional plane) as per the Drawings.

B.

Dissimilar Metals:

Where two dissimilar metals meet, install joint in such a manner that
metals do not contact each other by using a proper seal, sealant or compound.

C.

Drain Connections:

Install uni
t(s) as shown on Drawings, and according to
manufacturers installation instructions. Install drain valve and cap discharge of drain on
units provided with a drain connection.

D.

Outside Air Intakes:

Air handling related equipment that is immediately adjacen
t to
ducted outside air intakes shall have this duct section pitch toward the intake to drain to
the outside of the building. Solder or seal seams to form watertight joints. Blank off all
unused portions of louvers with fabricated insulated panels while

still abiding to net free
area requirements of the louvers. Where complete drainage to the exterior is not
possible, construct a stainless steel drain pan with a piped drain such that all moisture
entrained through the louver system will be precipitated
out of the air stream and drained
in this immediately adjacent duct section. The intent of this paragraph is to prevent any
and all moisture from entering the duct system beyond the louver


drainage section and
prevent any and all moisture from leaking o
ut and onto interior building surfaces.

E.

Electrical Centers:

Do not install air
-
handling related equipment over electrical
panelboards, switchgear, switchboards or motor control centers.

F.

Installation of Other Equipment:

Install all motor operated dampers;

and connect to or
install all equipment furnished by others. Provide all necessary blank
-
off plates or
transitions to facilitate control dampers as specified in
Section 15905


HVAC
Instrumentation and Section 15920


Pneumatic Controls
.

G.

Sealing Requirem
ents:

Seams and joint
-
sealing requirements shall meet SMACNA
Class
-
A.

H.

Mechanical Support:

Support coils, filters, dampers or other devices installed in or with
the air handling related equipment with removable angles or channels and fasteners.
Make all
connections to equipment including equipment furnished by others. Secure
frames with gaskets, nuts, bolts and washers. Refer to
Section 15060 Hangers and
Supports

and
Section 15715


Heating and Cooling Coils

regarding materials required for
supports and

mounting hardware.

I.

Duct Configuration General Purpose Vent Set:

The fan inlet and discharge ductwork
shall be configured and installed so as to
minimize “system effect” losses.

This shall be
accomplished by providing a minimum of one “fan wheel diameter
” of straight round
ductwork immediately upstream of the fan inlet connection and a minimum of three
diameters (of equivalent round duct) of straight ductwork downstream of the fan discharge
connection. Any necessary transition, elbow or offset fitting(s)

shall be installed upstream

or downstream of these lengths of straight duct.

J.

Special Purpose

1.

Compliance/Modifications:

The installation of each special purpose vent set shall
comply with the requirements of paragraph 3.05.I above except as modified for t
he
specific applications addressed below.

2.

High Velocity Discharge

a.

Fan Discharge Ductwork:

In roof mounted high velocity discharge type
exhaust fan applications it is often difficult to achieve the length of straight
ductwork at the fan discharge connectio
n that is required by the referenced
paragraph. In each such case, a minimum of 1
-
1/2 diameters (of equivalent
round duct) of straight ductwork shall be provided immediately downstream of
the fan discharge connection.

b.

Compliance:

In each roof mounted hig
h velocity discharge application the vent
set installation shall comply with the requirements of
Drawing 15800
-
1, Curb
-
Supported Fume Hood Exhaust Fan/Stack Installation.

3.

Laboratory / Corrosive Exhaust

a.

Flexible Duct Connectors:

In a laboratory / corrosive

exhaust application any
flexible connector that is installed at the fan inlet and/or discharge connection
shall be fabricated from a special corrosion resistant material. Use of standard
fabric is not acceptable.

K.

Vibration Field Balancing:
Perform field

mechanical balancing prior to allowing system
to be available for operation to meet the more stringent vibration tolerance specified in this
Section 15830


Fans,

Section 15720


Air Handling Units

and/or
Section 15070


Mechanical Sound, Vibration, and S
eismic Control
.

3.06

PREPARATION

A.

Surface Preparation:

Prepare surface by using power sanders or wire brushes to
remove materials such as rust and paint.

3.07

REPAIR AND RE
-
INSTALLATION

A.

Paint:

Use G90 Galvaneal or Zincgrip where touch
-
up painting is required to pre
vent
rusting of raw edges.

B.

Rework:

Provide quality work in like manner as initial installation, replacing all damaged
components. Install materials conforming to the same criteria as outlined in these
Specifications and conforming to SMACNA as previously
described.

3.08

CLEANING

A.

Cleanliness:

Standards from National Air Duct Cleaners Association, NADCA for HVAC
& Duct Systems shall be utilized for determining the need for and the extent of cleaning
that will be required. These standards will be used to resolve

any related issues.

B.

Fees:

The University of Illinois will not be responsible for any fees associated with
professional testing, cleaning, equipment replacement and/or repair back to like “new”
conditions if so jointly determined by the Engineer and
\

o
r recommended by the UIUC
O&M Commissioning and Inspection Team as a result of implementing testing under the
NADCA standards.

C.

Coordinate:

This section with all other related HVAC sections.

D.

Cleaning agents:

Use only non
-
hazardous non
-
toxic cleaning age
nts and materials.
Provide MSDS cut sheets upon request.

3.09

TESTING, BALANCING A
ND COMMISSIONING

A.

Testing and Balancing:

Refer to
Section 15950


Testing and Balancing

for related
Criteria.

B.

Coordinate:

with the Engineer and the UIUC O&M Commissioning

and In
spection Team.

END OF SECTION
15830

This section of the
UIUC Facilities Standards

establishes minimum requirements only.

It should not be used as a complete specification.