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IV−CONFIGURATION MODIFICATIONS
CB26UH and CBX26UHunits are factory−assembled and
configured for installation in upflow or horizontal left−hand
air discharge applications. A kit is available to convert units
for downflow applications. See OPTIONAL ACCESSO-
RIES at the front of this manual.
If the unit needs to be modified from its original configura-
tion, use the following procedures. All procedures assume
the unit has not been modified from the factory.
General Information
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, person-
al injury or loss of life. Installation and service must
be performed by a qualified installer or service
agency.
Each unit consists of a blower assembly, refrigerant coil,
and controls, in an insulated galvanized steel factory fin-
ished enclosure. Knockouts are provided for electrical wir-
ing 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, a filter rack must
be formed using factory−supplied flanges. Lay the unit on its
back and pry out the filter rack tabs as shown in figure 5.
Filter Rack Tabs
FIGURE 5
Upflow Application
1. The air handler must be supported on the bottom only
and set on solid floor or field-supplied support frame.
Securely attach the air handler to the floor or support
frame.
2. If installing a unit in an upflow application, remove the
horizontal drain pan; it is not required in upflow air dis-
charge installations.
3. Place the unit in desired location. Set unit so that it is
level. Connect return and supply air plenums as re-
quired using sheet metal screws.
4. Install units that have no return air plenum on a stand
that is at least 14" from the floor. This will allow proper
air return.
FIGURE 6
Upflow Configuration
HORIZONTAL
DRAIN PAN
(Remove for best
upflow performance)
UPFLOW
DRAIN PAN
UPFLOW DRAIN
CONNECTIONS
(Both sides; use
on side or other)
HORIZONTAL
DRAIN
CONNECTIONS
(Both sides; Not
used)
Horizontal Applications
NOTE − When the unit is installed in horizontal applications,
a secondary drain pan is recommended. Refer to local
codes.
This unit may be installed in left−hand or right−hand air dis-
charge horizontal applications. Adequate support must be
provided to ensure cabinet integrity. Ensure that there is ad-
equate room to remove service and access panels if instal-
ling in the horizontal position.
1. Determine whether left-hand or right-hand air dis-
charge is required. If right-hand is required, perform
Right−Hand Discharge Modification.
See next page.
2. Determine knockouts required for drain line connec-
tions.
3. With access door removed, knock out drain line open-
ing for installing drain lines.
4. Set unit so that it is sloped (up to 1/4 inch) toward the
drain pan end of the unit.
5. The horizontal configuration is shown in figure 7.
FIGURE 7
Left−Hand Air Discharge Configuration
LEFT-HAND DRAINS
KNOCKOUT
Drains
AIR
FLOW
6. If the unit is suspended, the entire length of the cabinet
must be supported. If you use a chain or strap, use a
piece of angle iron or sheet metal attached to the unit
(either above or below) to support the length of the cab-
inet. Use securing screws no longer than 1/2 inch to
avoid damaging the coil or filter. See figure 8. Use sheet
metal screws to connect the return and supply air ple-
nums as required.