Carpigiani Vision Installation Manual
Installation and Maintenance Manual IM672-4
Vision™Air Handler
Sizes 003–090
Group: Applied Air
Part Number: IM672
Date: Ju
ly 2007
© 2007 McQuay International
Contents
General Information . . . . . . . . . . . . . . . . . . . . . . . . . 3
Receiving and Handling. . . . . . . . . . . . . . . . . . . . . 3
Unit Storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Installation Guidelines. . . . . . . . . . . . . . . . . . . . . . . 4
Service Clearances . . . . . . . . . . . . . . . . . . . . . . . . 4
Rigging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Unit Leveling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Assembling Sections . . . . . . . . . . . . . . . . . . . . . . . 5
Ceiling Hung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Panels, Frame Channels, and Doors. . . . . . . . . . . 8
Field Mounting Junction Boxes and
Other Components. . . . . . . . . . . . . . . . . . . . . . . . . 9
Face and Bypass Section Mounting . . . . . . . . . . . 9
Multizone Assembly. . . . . . . . . . . . . . . . . . . . . . . 11
Duct Connections. . . . . . . . . . . . . . . . . . . . . . . . . 12
Mounting Actuators . . . . . . . . . . . . . . . . . . . . . . . 13
Piping and Coils. . . . . . . . . . . . . . . . . . . . . . . . . . 13
Drain Pan Traps. . . . . . . . . . . . . . . . . . . . . . . . . . 16
Internal Isolation Assembly Adjustment. . . . . . . . 16
Electrical Installation . . . . . . . . . . . . . . . . . . . . . . 17
Operation Guidelines . . . . . . . . . . . . . . . . . . . . . . . 18
Startup Checks . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Fan Wheel Alignment. . . . . . . . . . . . . . . . . . . . . . 19
Operating Limits. . . . . . . . . . . . . . . . . . . . . . . . . . 21
Fan Vibration Levels . . . . . . . . . . . . . . . . . . . . . . 23
Service and Maintenance . . . . . . . . . . . . . . . . . . . 24
Periodic Service and Maintenance . . . . . . . . . . . 24
Ball Bearing Lubrication. . . . . . . . . . . . . . . . . . . . 24
Fan Drive Adjustments. . . . . . . . . . . . . . . . . . . . . 24
Fan Drive Belt Adjustment . . . . . . . . . . . . . . . . . . 28
Front Load Filter Option . . . . . . . . . . . . . . . . . . . . 29
Filter Gauges . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Maintaining the Coil . . . . . . . . . . . . . . . . . . . . . . . 30
Winterizing Water Coils . . . . . . . . . . . . . . . . . . . . 30
Removing and Replacing Components . . . . . . . . 30
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Warranty Return Material Procedure . . . . . . . . . . 33
Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . 33
General Information
General Information
Vis ionTM 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. Install this
equipment 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, fins, clips, and such items inherently have
sharp edges; the installer should exercise caution.
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.
Receiving and Handling
1 Carefully 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.
2 Vision 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.
3 Take 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.
4 Handle 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.
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.
Unit Storage
Store unit on a level surface. If air handling units are stored for
any period of time, periodically rotate the fan wheel to prevent
permanent distortion of drive components. In addition, grease
may settle in the lower part of the bearing, which can lead to
oxidation on the upper portion of the bearing surface. Keep the
fan bearings lubricated.
Store units indoors in a clean, dry environment on a level
surface. Moisture, debris, and minerals can cause permanent
damage to the cabinet and components. Do not allow
coverings to trap moisture on the galvanized surface.
Nomenclature
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
CAH 003 G D A C
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
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
McQuay IM 672-4 3
Installation Guidelines
Installation Guidelines
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. 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). Electrical power devices that are mounted on
the side of the unit typically are up to 12" deep. See Figure 2.
Figure 1: Servicing Space Requirements
4 . 0 0 " b a s e r a i l e x t e n s i o n
Figure 2: Service Clearance for Electrical Power Devices
1 2 "
5 4 "
Rigging
Vision handlers ship as separate sections, completely
assembled, or in modules of assembled sections.
be rigged as it ships from the factory. Do not rig units after
assembly.
rail
When a unit is
, it
can be lifted using the 2" diameter lifting holes located in
provided with a factory-installed base
the corners of each shipping section. 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.
The unit must
3 0 . 0 0 "
W i d t h
4 . 0 0 "
3 0 . 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
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 unit.
Figure 3: Units on Base Rails
H e i g h t
4 McQuay IM 672-4
Installation Guidelines
)
S
t
a
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. 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: Fan Sections Stacked on Top of a Lower Section
Unit Leveling
Place the equipment on a flat and level surface. Where the
surface irregularities allow the equipment to distort, shim the
base of the unit 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. See Figure 6.
Figure 6: Leveling the Unit
h i m s e c t i o n s u n t i l
h e y a r e s t r a i g h t
n d l e v e l
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 "
I n s t a l l p a n e l s ( 4 )
R e m o v e
l i f t i n g
b r a c k e t s ( 4
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.
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. See
Figure 10.
Horizontal Airflow Section Mounting
1 Rig the unit into position and line shipping sections up in
direction of air flow.
2 Pull sections together to fasten. Use a furniture clamp or
straps and a ratchet to help pull the sections together
securely. See Figure 7.
3 If 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.
a To 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.
Shipping sections are
McQuay IM 672-4 5
Installation Guidelines
A
4 If no base rail is provided, fasten the unit in the same
manner on the bottom and top frame channels.
5 Once the sections are positioned together, remove the
fastener in each of the channel corners (on the mating edges
in the channel piece).
6 Place 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.
7 Replace the fasteners in their original position, through the
joining plate.
Figure 7: Horizontal Joining Sections
T o p
B o t t o m w i t h b a s e r a i l
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” on page 9 for
the exception to this procedure.
1 The 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.
2 The 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.
3 Cover 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. See Figure 8.
4 When 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. See Figure 8.
Figure 8: Vertical Inverted Joining Sections
. 3 1 2 - 1 8
x 1 0 0 b o l t
B
. 2 5 x 1 0 0 d r i l l s c r e w
B
A
R e p l a c e m e n t s c r e w
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 fastening steps on page 5 to
secure the opposite connection side. To fasten the connection
side, use the following procedure:
1 If 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. See Figure 9.
2 If 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. See Figure 9.
3 Place an L-shaped section joining plate (located in the
splice kit) over the coned hole in the channel.
4 Replace 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.
5 Position 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 9: Extended Coil Section Joining
T o p
V i e w A
B o t t o m
w i t h b a s e r a i l
A
( 2 ) 1 / 4 x 1
D r i l l S c r e w s
6 McQuay IM 672-4
Installation Guidelines
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. See Figure 10.
Figure 10: Internal Fastening
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.
See Figure 12.
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.
See Figure 13. 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 12: Ceiling Suspended w/o Base Rail (Unitized)
Construction
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 k e t .
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” on page 5.
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. See Figure 11.
Figure 11: Ceiling Suspended with Base Rail
Figure 13: Ceiling Suspended w/o Base Rail—Modular
Construction
McQuay IM 672-4 7
Installation Guidelines
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. See Figure 14.
Figure 14: Removing Panel Screws
Remove any
panel screws that
engage frame
ATTE NTION
Les bords tranchants et les surfaces des bobines sont un
risque de blessure. Ne les touchez pas.
CAUTION
DO NOT attempt to rotate the cup. Damage to the unit will
occur.
ATTE NTION
NE PAS tenter de faire tourner la cuvette (cup). Ceci va
dendomagger l’unité.
2 Insert 1/2" socket into cup and rotate 1/4 turn clockwise as
shown in Figure 15. If the cup and handle are on the left
side of the door, rotate 1/4 turn counterclockwise.
3 Rotate 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 cup and handle are on the
left side of the door, rotate the door handle 1/4 turn
counterclockwise and then 1/4 turn clockwise.
4 To prevent air leakage, tighten the door panels by adjusting
the jam nuts.
Remove panel
to remove frame
Fan Section Doors
Note – Opening fan section doors requires using a 1/2" socket
wrench, which satisfies ANSI standards and other codes
that require the “use of tools” to access compartments
containing moving parts or electrical wiring. See
Figure 15.
1 Remove padlock if one is present.
Figure 15: Opening Fan Section Door
Do Not Rotate Cup
Jam
Nuts
View from inside door
OPEN
CAUTION
Sharp edges and coil surfaces are a potential injury hazard.
Avoid contact with them.
8 McQuay IM 672-4
Installation Guidelines
Injected-Foam Insulated Panels
Vision air handlers now 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
1 Determine the number and location of holes required for
electrical conduit, piping, and control wiring as follows:
• Check that adequate space is available inside the unit for
conduit or pipe routing.
• Do not locate holes in a panel that provides access to key
maintenance components such as filters and fan
assemblies.
• Do not locate where the conduit or piping blocks airflow
or obstructs hinged access doors.
2 Once 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.
3 Seal 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 it is airtight, watertight, and so that
there is no exposed insulation.
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
Figure 16: Cutting/Sealing Injected-Foam Insulated Panels
Seal completely with silicone
Cut hole from both sides of panel
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.
sealant or duct seal compound
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 4, 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.
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.
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. 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, assemble
the fan and coil section first. Use the steps below for assembly.
See Figure 17.
McQuay IM 672-4 9
Installation Guidelines
r
1 Place 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.
2 Lift 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.
3 For 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.
4 Once 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.
5 Once the sections are lined up and in position, secure the
unit together by fastening joining plates to the unit.
Figure 17: Assembly of Fan Coil Sections
Joining
collar
Unit Sizes 040 to 090 External Face and Bypass Duct
Assembly
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. See Figure 18.
1 Position the unit shipping sections together and assemble in
the equipment room.
2 After 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.
3 If 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.
4 Once 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. See Figure 7 on page 6.
Figure 18: Assembly of Bypass Duct to Unit
J o i n i n g C o l l a r
10 McQuay IM 672-4
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
Installation Guidelines
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 20 on page 12) 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. See Figure 19.
1 If 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.
2
Once 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.
3 After the components in the multizone are fitted together,
fasten the joining plates to the corners in the unit exterior.
4 If a damper was ordered, assemble it to the section (see
“Multizone Damper Assembly” in the next column and
Figure 20 on page 12).
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:
1 First remove the side plate that encloses insulation from
both sides of the damper assembly.
2 Lift the damper assembly into position. See Figure 20.
3 Fasten the assembly to the frame channels within the
multizone openings.
4 Use caulking to seal up the areas around the unit frame
channel to prevent any air leakage.
5 After 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. See “Multizone
Damper Adjustment” on page 12.
Figure 19: Multizone Sections Assembly
Zone
damper
assembly
Upper unit—heating
Joining
collars
Cooling coilCooling coilDiffuser
McQuay IM 672-4 11
(and optional bypass)
Loading...