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
).
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 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:
1
First remove the side plate that encloses insulation from
both sides of the damper assembly.
2
Lift the damper assembly into position (
Figure 26
).
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 (refer to
Multizone
Damper Adjustment‚ page 16
).
