General Information - Lennox CB26UH Series Installation Instructions Manual

Select the final air discharge position which best suits the
site conditions. Consider required clearances, space,
routing requirements for refrigerant line, condensate
disposal, filters, duct system, wiring, and accessibility for
service, Refer to the air handler rating plate on the air
handler for specific information,
WARNING
If the free area is not known, assume a 25% free area for
wood or a 75% free area for metal louvers or grilles. Using
the louver dimensions and the 25% or 75% assumption,
determine if the open area meets the minimum open area
listed above,
If a return air plenum is used, the return air grille should be
immediately in front of the opening in the plenum to allow
for the free flow of return air. When not installed in front of
the opening, there must be adequate clearance around the
air handler to allow for the free flow of return air,
GENERAL INFORMATION
AkWARNING
NOTES -
During cooling operation, excessive sweating may occur if
the air handler is installed in a very humid space.
If installed in an unconditioned space, sealant should be
applied around the electrical wires, refrigerant tubing, and
condensate lines where they enter the cabinet.
Electrical wires should be sealed on the inside where they
exit the conduit opening. Sealant is required to prevent air
leakage into, and condensate from forming inside of, the
air handler, the control box, and on the electrical controls.
This unit is approved for installation clearance to
combustible material as stated on the unit rating plate.
Accessibility and service clearances must take
precedence over combustible material clearances.
The air handler must be installed so that free access is
allowed to the coil/filter compartment and blower/control
compartment.
Horizontal applications of the air handler must be installed
sloped (approximately 5/8 inch) toward the drain pan
openings to ensure proper condensate drainage.
NON-DUCTED RETURN CLOSET INSTALLATION
The air handler can be installed in a closet with a false
bottom to form a return air plenum. It may also be installed
with a return air plenum under the air handler,
Louvers or return air grilles are field-supplied. Local codes
may limit application of systems without a ducted return to
single story buildings.
When a CB(X)26UH unit is installed in a closet with a
Iouvered return opening, the minimum open area for the
louvers will be:
• 320 square inches for -018 and -024 models;
• 360 square inches for -030 and -036 models;
• 450 square inches for -042 thru -060 models,
CB(X)26UH units are factory-assembled and configured
for installation in upfiow or horizontal left-hand air
discharge applications,
Each unit consists of a blower assembly, refrigerant coil,
and controls, in an insulated galvanized steel factory
finished enclosure, Knockouts are provided for electrical
wiring entrance,
For ease in installation, it is best to make any necessary
coil configuration changes before setting air handler in
place,
If a filter is to be installed at the air handler, early models
require a filter rack be formed using factory-supplied
flanges, Lay the unit on its back and pry out the filter rack
tabs as shown in figure 1, Repeat procedure on opposite
side,
Figure 1. Filter Rack Tabs (Pre April 2006)
Later models are equipped with rails in which the filter
slides, Two screws and a bracket must be removed to
insert and remove the filter (see figure 2),
505059M 04_8
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