Vision CAC 003G - 090G Manual

Installation and Maintenance Manual IM 672-7
Vision™ Air Handler Group: Applied Air Systems
Part Number: IM 672
Date: October 2011
© 2011 McQuay International
Models CAC/CAH 003G – 090G

2McQuay IM 672-7
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
General Information . . . . . . . . . . . . . . . . . . . . . . . . .3
Receiving and Handling . . . . . . . . . . . . . . . . . . . . . .3
Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Unit Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Mechanical Installation . . . . . . . . . . . . . . . . . . . . . . . .5
Service Clearances . . . . . . . . . . . . . . . . . . . . . . . . . .5
Rigging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Unit Leveling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Assembling Sections . . . . . . . . . . . . . . . . . . . . . . . . .6
External Section-to-Section Mounting . . . . . . . . . 6
Horizontal Airflow Section Mounting . . . . . . . . . . .6
Vertical Inverted Airflow Section Mounting . . . . . .7
Extended Coil Section Mounting . . . . . . . . . . . . . .8
Side-by-Side Heatwheel Section Joining . . . . . . .8
Internal Section-to-Section Mounting . . . . . . . . . .9
Ceiling Hung . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Panels, Frame Channels, and Doors. . . . . . . . . . . .11
Panel Removal . . . . . . . . . . . . . . . . . . . . . . . . . .11
Frame Channel Removal . . . . . . . . . . . . . . . . . .11
Fan Section Doors . . . . . . . . . . . . . . . . . . . . . . .11
Injected-Foam Insulated Panels . . . . . . . . . . . . .12
Field Mounting Junction Boxes and
Other Components . . . . . . . . . . . . . . . . . . . . . . . . .12
Face and Bypass Section Mounting . . . . . . . . . . . .12
Bypass Into a Vertical Fan Section . . . . . . . . . . .12
External Face and Bypass Duct Assembly
(Sizes 040 to 090) . . . . . . . . . . . . . . . . . . . . . . . .13
Multizone Assembly . . . . . . . . . . . . . . . . . . . . . . . .14
Multizone Damper Assembly . . . . . . . . . . . . . . .14
Duct Connections . . . . . . . . . . . . . . . . . . . . . . . . . .16
Multizone Damper Adjustment . . . . . . . . . . . . . .16
Multizone, Mixing Box and Economizer Damper
Torque Requirements . . . . . . . . . . . . . . . . . . . . .16
Mounting Actuators . . . . . . . . . . . . . . . . . . . . . . . . .17
Face Bypass Damper Torque Requirements . . .17
Piping and Coils . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Water Cooling Coils . . . . . . . . . . . . . . . . . . . . . .17
Direct Expansion Coils . . . . . . . . . . . . . . . . . . . .17
Steam Coils . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Water Heating Coils . . . . . . . . . . . . . . . . . . . . . .20
Drain Pan Traps . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Internal Isolation Assembly Adjustment . . . . . . . . .20
Electrical Installation . . . . . . . . . . . . . . . . . . . . . . . . .22
Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Control Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Startup Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Before Starting the Unit . . . . . . . . . . . . . . . . . . . . . 23
Fan Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
After 48 Hours of Operation . . . . . . . . . . . . . . . . . . 24
Fan Wheel Alignment . . . . . . . . . . . . . . . . . . . . . . . 24
Operating Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Fan Vibration Levels . . . . . . . . . . . . . . . . . . . . . . . 28
Vibration Causes . . . . . . . . . . . . . . . . . . . . . . . . 28
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Periodic Maintenance . . . . . . . . . . . . . . . . . . . . . . 29
Ball Bearing Lubrication . . . . . . . . . . . . . . . . . . . . . 29
Motor Bearings . . . . . . . . . . . . . . . . . . . . . . . . . 29
Fan Shaft Bearings . . . . . . . . . . . . . . . . . . . . . . 29
Fan Drive Adjustments . . . . . . . . . . . . . . . . . . . . . . 30
VM/VP Variable Pitch Key Type Sheaves . . . . . 30
LVP Variable Speed Sheaves . . . . . . . . . . . . . . 31
MVP Variable Speed Sheaves . . . . . . . . . . . . . 32
Fan Drive Belt . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Front Load Filter Option . . . . . . . . . . . . . . . . . . . . . 34
Filter Gauges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Coils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Winterizing Water Coils . . . . . . . . . . . . . . . . . . . 35
Removing and Replacing Components . . . . . . . . . 35
Removing a Side or Top Panel . . . . . . . . . . . . . 35
Removing a Frame Channel . . . . . . . . . . . . . . . 35
Removing the Fan Section . . . . . . . . . . . . . . . . 35
Removing and Replacing the Coil . . . . . . . . . . . 35
Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . 37
Service and Warranty Procedure . . . . . . . . . . . . . . 38
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Warranty Return Material Procedure . . . . . . . . . . . 38
Check, Test, and Start Procedure Form . . . . . . . . . 39
Quality Assurance Survey Report . . . . . . . . . . . . . 41

McQuay IM 672-7 3
Introduction
Introduction
General Information
VisionTM air handlers are not designed to be weather resistant.
Do not install them outdoors.
The system design and installation must follow accepted industry
practice as described in the ASHRAE Handbook, the National
Electric Code, and other applicable standards. This equipment
must be installed in accordance with regulations of authorities
having jurisdiction and all applicable codes.
Installation and maintenance must be performed by qualified
personnel familiar with applicable codes and regulations and
experienced with this type of equipment. Sheet metal parts,
self-tapping screws, clips, and such items inherently have
sharp edges; the installer should exercise caution.
Receiving and Handling
1Carefully check items against the bills of lading to verify
all crates and cartons have been received. Carefully inspect
all units for shipping damage. Report damage immediately
to the carrier and file a claim.
2Vision air handler units are constructed of galvanized or
painted steel and are inspected thoroughly before leaving
the factory. Take care during installation to prevent damage
to units.
3Take special care when handling the blower section. All
fans are dynamically balanced before leaving the factory.
Rough handling can cause misalignment or a damaged
bearings or shaft. Carefully inspect fans and shaft before
unit installation to verify this has not happened.
4Handle the zone damper of the multi-zone units with
special care. Zone dampers are set and inspected before
leaving the factory, but should be checked on arrival to the
job to verify the bell arm and connecting rod set screws did
not become loose in shipment.
Note: Screws, bolts, etc., for assembling sections are
supplied in a bag attached to each section. All
necessary gasketing is applied in the factory for
section-to-section mounting.
Nomenclature
CAUTION
Sharp edges and coil surfaces are a potential injury hazard.
Avoid contact with them.
ATTENTION
Les bords tranchants et les surfaces des bobines sont un
risque de blessure. Ne les touchez pas.
CAH 003 G D A C
Model
CAH = Custom modular air handler
CAC = Custom modular component
Nominal unit size
(cataloged size—nominal square foot of coil)
003, 004, 006, 008, 010, 012, 014, 017,
021, 025, 030, 035, 040, 050, 065, 080, 085, 090
Vintage of McQuay air handling unit
Unit cross section
C = Standard unit cross section
M = Custom size cross section
Motor location
A = Motor along side of fan housing
D = Motor down stream of belt drive
plenum fan
F = Motor on inline fan
G = Motor downstream of direct drive
plenum fan
H = Motor downstream of fan array
T = Motor behind twin fan housing
Unit type/coil position
B = Blow-through cooling coil location
D = Draw-through cooling coil location
H = Heating only
V = Vent only
M = Multizone

4McQuay IM 672-7
Introduction
Unit Storage
•Store on a level surface in a clean, dry location where
temperature can be controlled if possible.
•Pack fan and motor bearings (unless motor bearings are
sealed) with compatible grease with the shaft stationary.
After grease has been installed, rotate shaft about 10
rotations.
•Isolate unit from shock and vibration.
•Once a month, rotate shaft a minimum of 10 revolutions.
Insure the stopped position is different than the original
position.
•Coat shafts with lubricant as needed to prevent corrosion.
•A descant bag may be hung in the interior of the unit to
minimize corrosion in humid storage environments.
•Do not clean galvanized steel surfaces with oil dissolving
chemicals. This may remove the protective coating and
accelerate corrosion.
•Do not allow coverings to trap moisture on galvanized
surfaces.
Belt driven fans:
•Reduce belt tension by at least 50% or remove the belts.
Remove belts if they will be subjected to temperatures
exceeding 85° F to avoid deterioration.
• Remove belt guard when adjusting belts
• Reduce belt tension prior to removing or installing belts.
Removing or installing tensioned belts may cause per-
sonal injury and damage to the sheaves, belts, bearings or
shafts.
•Adjustable sheaves should be opened as wide as possible
and the adjustment threads lubricated so they do not corrode.
Be careful not to put lubricant on the belt running surface
Prior to start up:
•Set screws on bearings, fan wheels, and sheaves need to be
checked for proper torque. Also check bolt torque for any
taper lock hubs either on the wheel or sheaves.
•Check sheaves for corrosion. Significant corrosion can cause
belt or sheave failure.
•Purge old grease from fan bearings while rotating the shaft
to distribute the new grease evenly and prevent bearing seal
failure.
•Correctly align and tension belts. See General Rules of
Tensioning‚ page 33.

McQuay IM 672-7 5
Mechanical Installation
Mechanical Installation
Service Clearances
In addition to providing adequate space around the unit for
piping coils and drains, access to at least one side of the unit is
always required to allow for regular service and routine
maintenance, which includes filter replacement, drain pan
inspection and cleaning, fan bearing lubrication, and belt
adjustment. Provide sufficient space—at least equal to the
length of the coil—on the side of the unit for shaft removal and
coil removal. Space, at least equal to the length of the side coil,
is required for coil removal. Space, at least equal to the fin
height, is required for top coil removal. See Figure 1 for
servicing space requirements.
For routine maintenance purposes, access normally is obtained
through the access doors or by removing panels. Fan and filter
sections are always provided with a service door on one side of
the unit. If requested, doors can be provided on both sides of
the unit. Optional service doors are available for most section
types and are provided based on customer request.
If component replacement is required, the top panel also can
be removed. If necessary, the unit can be disassembled.
Maintain at least 54" of clearance in front of electrical power
devices (starters, VFDs, disconnect switches and combination
devices). Electrical power devices that are mounted on the side
of the unit typically are up to 12" deep (Figure 2).
Figure 1: Servicing Space Requirements
Figure 2: Service Clearance for Electrical Power Devices
Rigging
Vision air handlers ship as separate sections, completely
assembled, or in modules of assembled sections. The unit
must be rigged as it ships from the factory. Do not rig units
after assembly. When a unit is provided with a
factory-installed base rail, it can be lifted using the 2" diameter
lifting holes located in the corners of each shipping section
(Figure 3). If a unit does not have a base rail, rig it using straps
or a sling. Fasten the strapping under the skid that ships with
the section (Figure 4).
To prevent damage to the unit cabinetry, use spreader bars.
Position spreader bars to prevent cables from rubbing the
frame or panels. Before hoisting into position, test lift for
stability and balance. Avoid twisting or uneven lifting of the
unit.
Figure 3: Units on Base Rails
4 . 0 0 " b a s e r a i l e x t e n s i o n
W i d t h
3 0 . 0 0 " 4 . 0 0 " W i d t h o f c o i l s e c t i o n
W i d t h o f
f a n s e c t i o n
3 0 . 0 0 "
H e i g h t
54"
12"

6McQuay IM 672-7
Mechanical Installation
Figure 4: Units on Skids
Fan sections greater than 108" wide that are stacked on another
section are constructed with internal fan support frames that
have integral lifting brackets (Figure 5). After the fan section
is placed in position, remove and discard the lifting brackets.
Install the small panels provided to complete the unit cabinet
areas where the lifting brackets were located.
Figure 5: Large Fan Sections Stacked on Top of a Lower
Section
Unit Leveling
Place the equipment on a flat and level surface. Where the
surface irregularities could cause the equipment to distort, use
a shim so the base of the unit is a straight line. Uneven or
distorted sections cause misfit or binding of the doors and
panels and improper draining of drain pans.
Units that are over 108" wide must rest on a flat surface for the
entire width of the base rails or must be shimmed at one or
more points along the length of the rails to prevent distortion
or sagging of the support rails (Figure 6).
Figure 6: Leveling the Unit
Assembling Sections
External Section-to-Section Mounting
Vision air handling units can ship fully assembled or as
separate shipping sections. Rig units that require field
assembly of shipping sections into position first. Shipping
sections are provided with a connection splice joint attached
on the leaving air side of the shipping section. The splice joint
is insulated and provides an air-tight seal between two sections
once they are assembled together. If the splice joint was bent
during shipping or rigging, restore it to its original position.
(Figure 16, page 9).
Horizontal Airflow Section Mounting
1Rig the unit into position and lineup shipping sections in
the direction of air flow. Pull sections together to fasten.
Use a furniture clamp or straps and a ratchet to help pull the
sections together securely (Figure 7).
2If the unit has a factory-installed base rail, first fasten base
rails together using the 3/8"-16 × 5" bolts located in the
splice kit provided with the unit.
aTo fasten two shipping sections together, four bolts are
needed (two on each side of the unit). The bolts are run
from one base rail into the other and fastened with a nut.
Complete each section bottom and top before attaching
additional sections.
R e m o v e
l i f t i n g
b r a c e t s ( 4 )
I n s t a l l p a n e l s ( 4 )
S h i m t o p r e v e n t
d i s t o r t i o n i f w i d t h
i s o v e r 1 0 8 "
S h i m s e c t i o n s u n t i l
t h e y a r e s t r a i g h t
a n d l e v e l

McQuay IM 672-7 7
Mechanical Installation
3If no base rail is provided, fasten the unit in the same
manner on the bottom and top frame channels.
4Once the sections are positioned together, remove the
fastener in each of the channel corners (on the mating edges
in the channel piece).
5Place a flat section joining plate (found in the splice kit)
over the two coned holes in the channels, so that the plate
spans the two sections.
6Replace the fasteners in their original position, through the
joining plate.
7For certain Vision Plus units, use the provided section
joining plates to fasten sections together. Space them as
shown in Figure 8. Using the provided ¼"-14 x 1" self
tapping screws, drill screw the joining plates into the frame
channel on each section, keeping unit sections tight
together. Follow instruction drawing included in the
assembly kit.
Figure 7: Horizontal Joining Sections
Figure 8: Frame Channel Stiffener Plates (Vision Plus Units
Only)
Vertical Inverted Airflow Section Mounting
For vertical or inverted arrangements, before lifting any top
mounting sections into place, rig into place and fasten together
the bottom tier of sections. Once bottom level sections are in
place and secured, lift stacked components and fasten using
the following procedure:
Note: See Face and Bypass Section Mounting‚ page 12 for the
exception to this procedure.
1The vertical/inverted section has a splice joint extending
out the top of the bottom joining section. Lower the section
that is to be positioned over the opening over the splice
joint to seal the connection between the two sections.
2The two sections are fastened together at the four bottom
corners of the mating edge. To fasten the corners located on
the end of the unit (where bottom section and top section
walls are flush with each other), remove the flat head
fasteners in the corners of both sections.
3Cover the coned holes with a flat joining plate and replace
the flat head fasteners in the holes to secure the joining
plate to both sections (Figure 9).
4When one section is deeper than the other, secure the two
sections using an L-shaped joining plate. To secure the
L-shaped bracket, remove the flat head fastener from the
corner, position the bracket over the hole, and replace the
flathead fastener with a 5/16"-18 × 1" bolt. Once the bolt is
in place, secure the bracket to the adjoining section with a
1/4 × 1" drill screw. Repeat the same procedure on both
corners of the unit (Figure 9).
Figure 9: Vertical/Inverted Joining Sections
T o p
B o t t o m w i t h b a s e r a i l
R e p l a c e m e n t s c r e w
. 3 1 2 - 1 8
x 1 0 0 b o l t
. 2 5 x 1 0 0 d r i l l s c r e w
A
B
BA

8McQuay IM 672-7
Mechanical Installation
Extended Coil Section Mounting
The extended coil section is 6" wider than all other sections of
the same unit size. The extension is always located on the coil
connection side of the unit. Because the extended coil section
is wider than other sections, it always ships as a separate
shipping section, and must be joined to other sections in the
field. To join an extended coil section to other components,
first follow the Horizontal Airflow Section Mounting‚ page 6
steps to secure the opposite connection side. To fasten the
connection side, use the following procedure:
1If the unit has a factory-installed base rail, the extended coil
section base rail is also 6" wider than the adjoining base
rail. Extended coil section base rails on the connection side
are fastened together using the 3/8"-16 by 3" bolts located
in splice kit provided with the unit (Figure 10).
2If no base rail is provided, the section is fastened in the
same manner on the bottom and top. Once the sections are
positioned together, remove the fastener in the corner of the
channel piece of the section mating to the extended coil
section (Figure 10).
3Place an L-shaped section joining plate (located in the
splice kit) over the coned hole in the channel.
4Replace the flat head fastener originally used in the corner
with a 5/16"-18 1" bolt and fasten it through the L-shaped
joining plate.
5Position the L-shaped joining plate so it butts up against the
extended coil section frame channel. To secure the plate to
the extended coil section, run two 1/4" × 1" drill screws
through the joining plate and into the frame channel.
Figure 10: Extended Coil Section Joining
Side-by-Side Heatwheel Section Joining
The side-by-side heatwheel will have two individual sections
parallel in the direction of airflow to be attached to either side.
Each section will attach to the heatwheel section and then to
the other parallel section.
1Rig the unit into position and line shipping sections up in
direction of air flow. Sections must be pulled together to
fasten using a furniture clamp or straps.
aIf the heatwheel section width is greater than 143”, then
rig the section into position using the 2 removable
lifting channels. After section is properly placed,
remove cotter pin and bolts from lifting channel and
discard as seen in Figure 11.
Figure 11: Cotter Pin and Bolt Detail
2If included, remove center base plates that are attached to
the base channels and save for step 4.
3If the unit has a factory installed base rail, fasten the base
rails together using the 3/8”-16 x 5” bolts located in the
splice kit provided with the unit.
aTo fasten two shipping sections together, two bolts are
required on the one side. The bolts are run from one
base rail into the other and fastened with a nut.
Complete each section bottom and top before attaching
additional sections.
4Assemble the center base plates as show in Figure 12,
leaving a 5/16” space between each plate to slide onto
section base channels to center point of section width.
Figure 12: Base Plate Detail
5Once the sections are positioned together, remove the
fastener in each of the channel corners (on the mating edges
in the channel piece).
6Place a flat section joining plate (found in the splice kit)
over the two coned holes in the channels, so the plate spans
the two sections.
77 Replace the fasteners in their original position, through
the joining plate.
88 Assemble the next section parallel to the assembled
section by following steps 1 – 7 above.
99 Using the 3/8”-16 x 1” bolts provided, fasten the two
parallel sections’ bases together as seen in Figure 13.
V i e w A
B o t t o m
w i t h b a s e r a i l A
T o p
( 2 ) 1 / 4 x 1
D r i l l S c r e w s

McQuay IM 672-7 9
Mechanical Installation
Figure 13: Base Section Detail
10 Using appropriate safety equipment if necessary, remove
the fastener in each of the channel corners on the top
between the two parallel sections and discard.
11 Use the 2 x 2 holed splice plate with 2 x 5/16”-18 x 1”
screws and 2 x ¼” drill screws. The 2 x 5/16”-18 x 1”
screws will go into the frame channel holes and the 2 x ¼”
drill screws will go into the heatwheel frame channel as
show in Figure 14.
Figure 14: Frame Channel Detail
Internal Section-to-Section Mounting
If desired, shipping sections can be fastened together
internally. To fasten internally, run field-provided #10 sheet
metal screws or drill screws (4" long maximum) through the
interior frame channel of one unit into the splice joint of the
neighboring section.
The section-to-section splice joint is always provided on the
leaving air side of a shipping section and seals against the
frame channel on the entering-air side of the adjoining section.
Align the splice joint to seat into the mating gasket to provide
an air seal. If the splice joint was bent during shipping or
rigging, restore it to its original position (Figure 16).
For Vision Plus units, ensure that the D-gasket is attached to
the entering air side frame channel (Figure 15). If it has
dislodged during shipping, restore to original location.
Figure 15: D-Gasket Placement Detail (Vision Plus Units
only)
Figure 16: Internal Fastening
V i e w A
A
S p l i c e C o l l a r
m u s t b e a l i g n e d
t o s e a l t o g a s e t .

10 McQuay IM 672-7
Mechanical Installation
Ceiling Hung
When a unit is ceiling hung, support it with a base rail, angle iron,
or channel. The Vision air handler is not designed to be suspended
from the top of the unit. Before hanging, rig and completely
assemble the unit. See Assembling Sections‚ page 6.
Ceiling Hung Using Base Rail
The optional base rail provided by the factory has 5/8" diameter
holes in each corner to run hanger rods through. To properly
support the unit and maintain unit integrity, support each
shipping section with hanger rods in each corner (Figure 17).
Figure 17: Ceiling Suspended with Base Rail
Ceiling Hung Using Angle Iron Channel
Install field-provided angle iron or channels per SMACNA
guidelines. When a unit is unitized (ships in one piece), channel
support each component under the unit width (Figure 18).
When a unit is sectionalized (ships in multiple sections), channel
support each component under the unit width and provide support
under the full length of the unit base (Figure 19). Locate hanger
rods so they do not interfere with access into the unit.
Ceiling suspension using the unit base rails is limited to
unit cabinet widths less than 108". Support units with
cabinets 108" wide and greater with structural members
designed to support the unit at the ends and at intermediate
points along the base rails.
Figure 18: Ceiling Suspended w/o Base Rail—Unitized
Construction
Figure 19: Ceiling Suspended w/o Base Rail—Modular
Construction
NOTE
The supporting angle iron must fully support the 2" frame
channel at each section joint.

McQuay IM 672-7 11
Mechanical Installation
Panels, Frame Channels, and Doors
Panel Removal
To remove a side or top panel, remove the flat head Torx 30
fasteners along the sides of the panel. Lift off the panel after
removing all fasteners.
Frame Channel Removal
Frame channels that run the length of the unit along the top can
be removed to allow access to both the side and top of the unit.
To remove the frame channel, first remove the side panel(s).
Once the side panel is off, remove the flat head Torx 30
fasteners in the corner of the frame channels. Then pull the
frame channel out the side. Remove any panel screws that are
within one inch of the of the frame since they are engaged into
the gasketed flange of the frame (Figure 20).
Figure 20: Removing Panel Screws
Fan Section Doors
Note: Opening fan section doors requires using a 1/2" socket
wrench (Figure 21), which satisfies ANSI standards and
other codes that require the “use of tools” to access
compartments containing moving parts or electrical
wiring.
1Insert 1/2" socket and rotate 1/4 turn clockwise as shown in
Figure 21. If the handle is on the left side of the door, rotate
1/4 turn counterclockwise.
2Rotate the door handle 1/4 turn clockwise and then 1/4 turn
counterclockwise to release any internal pressure or
vacuum and open the door. If the handle is on the left side
of the door, rotate the door handle 1/4 turn
counterclockwise and then 1/4 turn clockwise.
3To prevent air leakage, tighten the door panels by adjusting
the jam nuts.
Figure 21: Opening Fan Section Door
CAUTION
Sharp edges and coil surfaces are a potential injury hazard.
Avoid contact with them.
ATTENTION
Les bords tranchants et les surfaces des bobines sont un
risque de blessure. Ne les touchez pas.
Remove panel
to remove frame
Remove any
panel screws that
engage frame

12 McQuay IM 672-7
Mechanical Installation
Injected-Foam Insulated Panels
Vision air handlers are furnished with double-wall, injected-
foam insulated panels. Foam panels are stronger, more rigid,
and lighter than panels with fiberglass insulation. The
insulation R-value is improved to 13. However, foam
insulation can burn when exposed to flame or other ignition
sources and release toxic fumes. Take care in cutting and
sealing all field-cut openings in these panels.
Panel Cutting Procedure
1Determine the number and location of holes required for
electrical conduit, piping, and control wiring as follows
(also refer to Figure 22):
aCheck that adequate space is available inside the unit
for conduit or pipe routing.
bDo not locate holes in a panel that provides access to
key maintenance components such as filters and fan
assemblies.
cDo not locate where the conduit or piping blocks
airflow or obstructs hinged access doors.
2Once a proper location is determined, drill a small pilot
hole completely through the panel. Then use a sharp hole
saw or a saber saw and cut from each side of the panel.
3Seal the double-wall panel on each side with an industrial/
commercial grade silicone sealant or duct seal compound.
It is extremely important to seal each panel hole or
penetration securely so that it is airtight, watertight, and
that there is no exposed foam insulation.
Figure 22: Cutting/Sealing Injected-Foam Insulated panels
Field Mounting Junction Boxes and
Other Components
For field mounting 4" × 4" or smaller junction boxes to the
standard panel exterior, use a minimum quantity of four, 3/16"
diameter pop rivets. Do NOT use self-tapping drill screws.
They will not tighten nor secure properly and panel
damage can occur.
If larger, heavier components require mounting on unit panels,
use through-bolts with flat washers through both outer and
inner panels. To maintain panel integrity, seal both ends with
an industrial/commercial grade silicone sealant or duct seal
compound.
The unit frame channel is another excellent location for
securing heavier components; self-tapping screws are not
acceptable. Ensure that the location permits the full operation
of all access doors and panels and does not interfere with other
vital components.
Face and Bypass Section Mounting
Internal face and bypass, and external face and bypass for sizes
003 to 035 are mounted together using the instructions for
horizontal components and do not require additional
instruction.
For all size units that bypass directly into a vertical fan section
and for sizes 040 to 090 with external face and bypass, use the
following instructions.
Bypass Into a Vertical Fan Section
Vertical coil sections and the top mounted fan section always
ship separately and must be mounted together at the job site.
The vertical coil section and the bypass duct each has a joining
collar mounted on the leaving air side of the section and duct,
respectively (Figure 23). The mounting collar fits into the side
(bypass) and bottom (vertical coil section) openings in the fan
section. To correctly position the collars in the fan openings,
WARNING
Flame and smoke can cause equipment
damage, severe personal injury, or
death.
Before operating unit, seal all piping and
wiring holes on both inner and outer panels
with an industrial grade silicone sealant or
duct seal compound. Do not use a cutting
torch or expose panel to fire. Panel
damage can occur.
WARNING
La fumée et les flammes peuvent
endommager le matériel et causesr des
blessures graves ou la mort.
Avant d’utiliser le dispositif, obturer tous les
trous de passage de tubulures et de fils
ménagés dans les panneaux intérieurs et
extérieurs au moyen d’une pâte à base de
silicone ou d’un mastic d’étanchéite â
conduits de qualité industrielle.
Ne pas se servir d’un chalumeau coupeur ni
exposer les pannequx à une flamme nue
pour ne pas risquer de les endommager.
Cut hole from both sides of panel
Seal completely with silicone
sealant or duct seal compound
Prop 65—Substances in fuel or from fuel combustion can cause personal injury or death,
and are known to the State of California to cause cancer, birth defects or other reproductive harm.

McQuay IM 672-7 13
Mechanical Installation
assemble the fan and coil section first. Use the steps below for
assembly.
1Place the vertical coil section in position. If an access
section is positioned downstream from the coil section and
not already assembled to the coil section, secure the two
sections together.
2Lift the fan section on top of the vertical coil section, taking
care to line up the joining collar in the bottom of the fan
section.
3For sizes 003 to 035, the bypass duct is integral to the unit
construction and does not require attachment to the bypass
section. For sizes 040 to 090, position and assemble the
bypass duct to the bypass section before joining to the fan.
4Once the fan is positioned on top of the vertical coil section
and the bypass duct and bypass section are assembled,
position the two assemblies and line up the joining collars
with the openings in the fan and vertical coil section.
5Once the sections are lined up and in position, secure the
unit together by fastening joining plates to the unit.
Figure 23: Assembly of Fan Coil Sections
External Face and Bypass Duct Assembly
(Sizes 040 to 090)
When unit sizes 040 to 090 are ordered with external face and
bypass, the bypass duct ships separately and must be attached
to the unit in the field. The joining of the bypass duct to the unit
must be done after the unit is assembled. Also, if the bypass
duct is over 90" long, the duct does not ship in one piece and
must be field assembled. The field assembly of the bypass duct
to the unit requires the following steps (also refer to Figure 24).
1Position the unit shipping sections together and assemble in
the equipment room.
2After the unit is assembled, lift the duct into position over
the unit. Joining collars are shipped factory assembled to
the unit and duct. There is a joining collar located in the top
of the bypass opening and in the leaving air side of the
bypass duct. These joining collars are used to provide air
seals. Line up the duct with the top openings in the unit.
3If the bypass duct is longer than 90", the duct ships in more
than one piece and must be field assembled. Place the piece
of duct that has the joining collar on the bottom on top of
the unit first. Once it is in place, position the other piece of
duct. Take care to fit the splice collar into the first piece of
duct and then lower the other end into the bypass opening.
4Once the duct is positioned correctly, fasten the duct pieces
together with the joining plate provided. To do this, remove
the fasteners in the corners of the duct assemblies, place the
plate over the holes in the corners, and then replace the
fasteners (Figure 7, page 7).
Figure 24: Assembly of Bypass Duct to Unit
Joining
collar
J o i n i n g C o l l a r
J o i n i n g C o l l a r
J o i n i n g C o l l a r

14 McQuay IM 672-7
Mechanical Installation
Multizone Assembly
The multizone section may ship completely assembled or it
may ship in numerous pieces. Whether the section ships in a
single piece or multiple pieces depends on customer
requirements and the unit size. When a multizone section is
over 90" high or 90" wide, split it into sections for shipping.
The unit may ship in 1, 2, 3, 4, or 5 separate pieces. Typically,
the multizone damper assembly ships separately (see
Multizone Damper Assembly in the next column and
Figure 26) and must be attached at the job site. Attach the
damper after the other components are assembled. Use the
instructions below for assembling the multizone section (also
refer to Figure 25).
1If the diffuser and the cold deck section ship separately,
join them together first. The joining collar mounted in the
diffuser fits into the entering air side of the coil section.
Line up the two sections and fasten together.
2Once the diffuser and cold deck sections are joined, lift the
hot deck and bypass sections in place on top of the diffuser/
cold deck section. If possible, assemble the hot deck and
bypass section (if there is one) together before lifting on
top. There always is a joining collar in the diffuser. The
joining collar provides the seal between the sections joints.
It is important to line up and fit the collar in the hot deck
and bypass section. For vertical applications, the cold deck
also has a joining collar in the discharge opening. This
collar fits in the bottom of the vertical bypass section.
3After the components in the multizone are fitted together,
fasten the joining plates to the corners in the unit exterior.
4If a damper was ordered, assemble it to the section (see
Multizone Damper Assembly in the next column and
Figure 26).
Note: Verify that the joining collars are aligned to seat into the
gasket. Straighten any collars distorted from shipping or
from rigging.
Multizone Damper Assembly
When a multizone unit is ordered with dampers, depending on
the multizone configuration and size, the damper assembly
may ship separately (all horizontal and units with a total height
over 90").
When the dampers are not factory assembled to the unit, they
ship to the job site on a skid. An assembly kit with screws and
an instruction drawing are included with the damper for field
assembly to the unit.
To assemble:
1First remove the side plate that encloses insulation from
both sides of the damper assembly.
2Lift the damper assembly into position (Figure 26).
3Fasten the assembly to the frame channels within the
multizone openings.
4Use caulking to seal up the areas around the unit frame
channel to prevent any air leakage.
5After caulking, put the side plates back in place and secure.
Damper shaft extensions are provided on both ends of the
damper assembly for actuation. The dampers are linked
together by a linkage bar on both ends of the damper. The
linkage bar is cut at the time of installation to divide the
damper into the required number of zones (refer to Multizone
Damper Adjustment‚ page 16).

McQuay IM 672-7 15
Mechanical Installation
Figure 25: Multizone Sections Assembly
Figure 26: Multizone Damper Assembly
Cooling coilCooling coilDiffuser
Joining
collars
Zone
damper
assembly
Upper unit—heating
(and optional bypass)
S e a l w i t h c a u l
o n b o t h s i d e s .
A i r f l o w
R i g h t h a n d c o i l
R e m o v e a s s e m b l y
i n s u l a t i o n p a n e l
c o v e r f r o m d a m p e r
t o a l l o w c a u l i n g .
D r i l l s c r e w i n t o
c a b i n e t f r a m e
w i t h # 1 0 A B x . 5 0
d r i l l s c r e w .
1 / 4 A B x . 5 0
O pen dam per blades
t o a l l o w f a s t e n i n g .
I f a i r f l o w b a l a n c e p l a t e s
a r e p r e s e n t , t h e n i n s t a l l
d a m p e r s s o t h a t t h e b a l a n c e
p l a t e s a r e o n t h e b o t t o m
of each zone.
D a m p e r b l a d e s
b r o e n o u t t o
s h o w a i r f l o w
balance plates
b e h i n d t h e m .

16 McQuay IM 672-7
Mechanical Installation
Duct Connections
Use flexible connectors on the outlet and inlet duct
connections of all units. Each zone divider has a W-shaped
duct clip. Insert ductwork into this clip (Figure 27).
Figure 27: Duct Connectors
Note: Before connecting to ductwork, refer to Multizone
Damper Adjustment below.
Multizone Damper Adjustment
The installer must clear the damper assemblies of construction
dirt and debris. These materials result in higher torque
requirements and may bend or damage damper components.
Before you begin:
1Verify that dampers are square and operating smoothly
before ducting.
2Install duct access panels on the downstream damper for
inspection and maintenance.
If multizone dampers do not close properly, adjust the blades
as follows:
1Loosen set screws in bell arms for all zones.
2Close all cold deck dampers tightly.
3Move bell arms so they are at a 45° angle to the vertical
center when viewing the zone dampers from the cold deck
end of the damper section (Figure 28).
aTwo-deck zone dampers—The cold deck closes when
the bell arms are 45° from the vertical center. The hot
deck closes when the bell arms are 45° clockwise from
the vertical center.
bThree-deck zone dampers—The cold deck closes when
the bell arms are 45° clockwise from the vertical center.
The hot deck closes when the bell arms are 45°
counterclockwise from the vertical center.
4Tighten set screws on bell arms while holding the dampers
closed.
5All zone damper blades should close properly. If one or a
few zones do not close completely, repeat the procedure for
these zones.
Figure 28: Bell Arms at 45° Angle to Vertical Center
Multizone, Mixing Box and Economizer
Damper Torque Requirements
On multizone units, the actuator must drive the connection link
for proper damper actuation. Do not activate multiple dampers
must from the shaft extension opposite the connection link.
D u c t w o r D u c t c l i p
Z o n e d i v i d e r
45° 45°
C o n n . l i n
B e l l a r m
Z o n e d a m p e r l i n k a g e
45° 45°
B e l l a r m
I n s t a l l a t i o n m o d i f i c a t i o n f o r m u l t i p l e z o n e s
To divide the damper section into multiple zones, cut and remove sufficient
connecting link to allow adjacent zones to operate independently.
Note: The damper blades on two-deck dampers seal through several degrees
of shaft rotation.The damper blades can rotate 360° and do not engage a stop.
The hot deck blades are mounted at a 90° to the cold deck blades. Before
installing the zone duct, set up linkages and dampers and adjust. If adjustment
is required and access to the blades is restricted, observe the cold deck blade
position by removing the cabinet panel on the coil section.

McQuay IM 672-7 17
Mechanical Installation
Mounting Actuators
The installing contractor is responsible for the mounting of all
field-installed actuators. No provisions are made for the
location of these actuators due to the number of options and
arrangements available and the variety of specific applications.
Typically, actuators are mounted inside the cabinet. Provide
proper support for the actuator to avoid excessive stress in the
cabinet, linkage, or damper shafts.
Fresh air and return air dampers can be linked together and
driven from the same actuator if the dampers are the same size.
If the dampers are different sizes, they must be driven by
separate actuators and controlled appropriately. Exhaust
dampers are always driven by a separate actuator.
A typical rotary electric actuator can handle up to 40 sq. ft. of
damper. For pneumatic actuators, allow 5 in-lb per square foot
of damper area.
Face Bypass Damper Torque Requirements
Face and bypass dampers may or may not be linked together.
When dampers are placed before a single bank of coils, they
always are linked together and require a single actuator. When
dampers bypass a stacked or staggered coil, the dampers are
not linked and require multiple actuators. Unit sizes 040 to 090
provided with external face and bypass require three actuators.
Other arrangements with stacked or staggered coils require
two actuators. A damper shaft extension is provided.
Normally, the shaft extension is located on the drive side of the
unit, but it can be moved to the other side.
Face and bypass dampers have a torque requirement of
10 in-lbs per square foot of damper face area.
Piping and Coils
When designing and installing piping:
•Follow applicable piping design, sizing, and installation
information in ASHRAE handbooks.
•Observe all local codes and industry standards.
•Do not apply undue stress at the connection to coil headers;
always use a backup pipe wrench.
•Support pipework independently of the coils.
Water Cooling Coils
•Water supply, water return, drain, and vent connections
extend through the end panel of the coil section. All
connections are labeled on the end panel.
•Water supply and water return connections are typically
male NPT iron pipe.
•When installing couplings, do not apply undue stress to the
connection extending through unit panel. Use a backup
pipe wrench to avoid breaking the weld between coil
connection and header.
•Follow recommendations of the control manufacturer
regarding types, sizing, and installation of controls.
Direct Expansion Coils
•The coil distributor and suction connection extend through
the end panel of the coil section.
•Check nozzle in distributor for proper tonnage.
•When a field supplied thermostatic expansion valve is used,
it is located outside the unit and connected directly to the
distributor. Do not apply heat to the body of the expansion
valve.
•The thermostatic expansion valve must be of the external
equalizer tube type. Connect the 1/4-inch diameter external
equalizer tube provided on the coil to connection on
expansion valve.
•Use care when piping the system to see that all joints are
tight and all lines are dry and free of foreign material. For
CAUTION
Maximum damper rotation is 70°.
Maximum shaft torque is 205 inches/pound.
Greater rotation or torque can cause equipment damage.
ATTENTION
La rotation maximale des volets est de 70°.
Le couple (torque) maximum de l’arbre est de 205 po/lb.
Une plus grande rotation (ou torque) peut endommager
l’équipement.

18 McQuay IM 672-7
Mechanical Installation
Steam Coils
Piping (see Figure 29)
•All steam coils in units are pitched toward return connection.
•Steam supply and steam return connections typically are
male NPT iron pipe and are labeled on the end panel of coil
section. Connections extend through the coil section end
panel.
•When installing couplings, do not apply undue stress to the
connection extending through unit panel. Use a backup
pipe wrench to avoid breaking the weld between coil
connection and header.
•Support piping independently of coils and provide adequate
piping flexibility. Stresses resulting from expansion of
closely coupled piping can cause serious damage.
•Do not reduce pipe size at the coil return connection. Carry
return connection size through the dirt pocket, making the
reduction at the branch leading to the trap.
Coils
•Install vacuum breakers on all application to prevent
retaining condensate in the coil. Generally, the vacuum
breaker is connected between the coil inlet and the return
main. The vacuum breaker should be open to the
atmosphere, and the trap design should allow venting of
large quantities of air.
•Do not drip supply mains through the coil.
•Do not attempt to lift condensate when using modulating or
on/off control.
Traps
•Size traps in accordance with the manufacturers’
recommendations. Make sure that the required pressure
differential is always available. Do not undersize.
•Use float and thermostatic or bucket traps for low pressure
steam. On high pressure steam, use bucket traps. Use
thermostatic traps only for air venting.
•Use bucket traps for on/off control only.
•Locate traps at least 12 inches below the coil return
connection.
•Multiple coil installation
• Individually trap each coil or group of coils that is con-
trolled individually trapped.
• Coils in series—use separate traps for each coil, or bank
of coils.
• Coils in parallel—a single trap can be used, but an indi-
vidual trap for each coil is preferred.
• Do not attempt to lift condensate when using modulating
or on/off control.
•With coils arranged for series airflow, use a separate control
on each bank or coil in the direction of airflow.
Valves
•Do not use modulating steam valves on high pressure
systems.
•Properly size modulating valves. Do not undersize.
•Freezing conditions (entering air temperatures below 35°F).
• McQuay strongly recommends 5JA, 8JA, 5RA and 8RA
coils.
• Supply 5 psi steam to coils at all times.
•Do not use modulating valves. Provide control by face and
bypass dampers.
• Consider using two or three coils in series with two posi-
tion steam control valves on the coil or coils that handle
35°F or colder air. Use a modulating valve on the down-
stream coil to provide the desired degree of control.
• Thoroughly mix fresh air and return air before it enters the
coil. Also, to obtain true air mixture temperatures, prop-
erly locate temperature control elements.
• As additional protection against freeze-up, install the trap
sufficiently below the coil to provide an adequate hydro-
static head to remove condensate during an interruption in
the steam pressure. Estimate three feet for each 1 psi of
trap differential required.
• On startup, admit steam to coil ten minutes before admit-
ting outdoor air.
• Close fresh air dampers if steam supply pressure falls
below the minimum specified.

McQuay IM 672-7 19
Mechanical Installation
Figure 29: Piping Arrangements
Check Valve Strainer Gate Valve Control valve
modulating
two position
Float and
thermostatic trap
High Pressure (over 25 psi)
Low Pressure (to 25 psi)
5GA or 8GA coils. Note that the
addition of a vacuum breaker to
permit the coil to drain during
shutdown.
5TA, 8TA, or 5HA coils. Conden-
sate is lifted to overhead return
main
5JA or 8JA coil. Installed in series.
Note that each coil must have a
separate control valve and trap.
5RA, 8RA, or 5SA coils. Banked two
high, individual trapping of each coil as
shown is preferred.
5RA, 8RA, or 5SA coils. Installed
5J, 5G, 8J or 8G coils.

20 McQuay IM 672-7
Mechanical Installation
Water Heating Coils
•Water supply and water return connections extend through
the end panel of the coil section. All connections are labeled
on the end panel.
•Water supply and water return connections are male NPT
iron pipe.
•When installing couplings, do not apply undue stress to the
connection extending through unit panel. Use a backup pipe
wrench to avoid breaking the weld between the coil
connection and header.
•Follow recommendations of the control manufacturer
regarding types, sizes, and installation of controls.
•Do not use hot water coils with entering air below 40°F.
•If fresh air and return air are to be heated by a hot water coil,
carefully design the system to provide thorough mixing
before air enters the coil.
•To prepare coils for winter operation, see Winterizing Water
Coils‚ page 35.
Drain Pan Traps
Run drain lines and traps full size from the drain pan
connection. Install drain pan trap to allow condensate to drain
freely. On both blow-through and draw-through units, the trap
depth and the distance between the trap outlet and the drain
pan outlet must be twice the static pressure in the drain pan
section under normal operation so the trap remains sealed
(Figure 30).
Figure 30: Allow Adequate Distance Between Trap Outlet
and Drain Pan Outlet
Internal Isolation Assembly
Adjustment
On units with internally isolated fan and motor assemblies, the
assemblies are secured for shipment.
Before Operating the Unit:
Remove the shipping brackets and tie-down bolts (refer to
Figure 32 and Figure 33) and discard. The shipping brackets
located on the opposite drive side of the unit are difficult to
access from the drive side of the unit. Either remove them
before the unit is assembled, or remove the panel on the
opposite drive side to gain access.
The spring isolators under the four corners of the fan and
motor assembly are factory adjusted while the fan was not
running. With the unit operating at normal cfm and static
pressure, all the isolators should be at the same height opening
(Table 1 and Table 2). If adjustments are required, loosen the
1/2" cap screw on top of the isolator and turn the adjusting bolt
to lower or raise the fan and motor base. Retighten the cap
screw when adjustments are completed.
For models 040 through 090, the isolators should be at equal
height (6") during fan operation. Center the fan outlet in the
outlet panel opening. If adjustment is required, loosen the bolt
on top of the isolator assembly (Figure 31). Turn the
CAUTION
Improper installation, use, or maintenance of water heating
coils can cause equipment damage.
Read and follow instructions carefully.
ATTENTION
Si l’installation, l’utilisation ou l’entretien des
serpentins de chauffage à eau sont inadéquats,
ceci endommagera l’équipement.
Lire et suivre attentivement les instructions.
Pressure (P)
at the drain pan
2P
2P
Table 1: Motor Beside Fan Spring Mount Adjustments
Spring mount adjustment at rest
Fandischarge
position Top or bottom horz. H Downblast HUpblast H
Unit sizes 003 – 035
1 3.75 3.75 4.25
2 4.25 3.75 4.25
3 4.25 3.75 4.25
4 3.75 3.75 4.25
Unit sizes 040 – 090
1 6.00 6.00 6.50
2 6.50 6.00 6.50
3 6.50 6.00 6.50
4 6.00 6.00 6.50
Table 2: Motor Behind Fan Spring Mount Adjustments
Spring mount adjustment at rest
Fandischarge
position Top or bottom horz. H Downblast HUpblast H
Unit sizes 003 – 035
1 6.75 6.75 6.75
2 6.75 6.75 6.75
3 6.75 6.75 6.75
4 6.75 6.75 6.75
Unit sizes 040 – 090
1 6.75 6.75 6.75
2 6.75 6.75 6.75
3 6.75 6.75 6.75
4 6.75 6.75 6.75