Unit Support; Duct Connection; Downflow Discharge Application - Lennox KGB024 Installation Instructions Manual

S The heat exchanger, components, duct system, air
filters and evaporator coil must be thoroughly
cleaned following final construction clean-up.
S The unit operating conditions
cooling operation, ignition, input rate, temperature
rise and venting) must be verified according to these
installation instructions.

Unit Support

In downflow discharge installations, install the unit on a
non-combustible surface only. Unit may be installed on
combustible surfaces when used in horizontal discharge
applications or in downflow discharge applications when
installed on a T1CURB or K1CURB roof mounting frame.
KG/KC 024, 030, 036, 048, 060, 072 and 074 units are
installed on T1CURB frames. KG/KC 090 units are
installed on K1CURB frames.
NOTE - Securely fasten roof frame to roof per local codes.
A-Downflow Discharge Application
Roof Mounting with T1CURB or K1CURB
1- The T1CURB/K1CURB roof mounting frame must be
installed, flashed and sealed in accordance with the
instructions provided with the frame.
2- The T1CURB/K1CURB roof mounting frame should
be square and level to 1/16" per linear foot (5mm per
linear meter) in any direction.
3- Duct must be attached to the roof mounting frame
and not to the unit; supply and return plenums must
be installed before setting the unit.
Installer's Roof Mounting Frame
Many types of roof frames can be used to install the unit
depending upon different roof structures. Items to keep
in mind when using the building frame or supports are:
1- The base is fully enclosed and insulated, so an
enclosed frame is not required.
2- The frames or supports must be constructed with
non-combustible materials and should be square and
level to 1/16" per linear foot (5mm per linear meter)
in any direction.
(including airflow,
NOTE-When installing a unit on a combustible surface for
downflow discharge applications, a T1CURB/K1CURB
roof mounting frame is required.
B-Horizontal Discharge Applications
All exterior ducts, joints and openings in roof or building
walls must be insulated and weather-proofed with
flashing and sealing compounds in accordance with
applicable codes. Any duct passing through an
unconditioned space must be insulated.
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3- Frame or supports must be high enough to prevent
any form of moisture
Recommended minimum frame height is 14"
(356mm).
4- Duct must be attached to the roof mounting frame
and not to the unit. Supply and return plenums must
be installed before setting the unit.
5- Units require support along all four sides of unit base.
Supports must be constructed of steel or suitably
treated wood materials.
1- Units which are equipped with an optional
economizer and installed in horizontal airflow
applications must use a horizontal conversion kit.
2- Specified installation clearances must be maintained
when installing units. Refer to figure 1.
3- Top of support slab should be approximately 4"
(102mm) above the finished grade and located so no
run-off water from higher ground can collect around
the unit.
4- Units require support along all four sides of unit base.
Supports must be constructed of steel or suitably
treated wood materials.

Duct Connection

CAUTION
In downflow applications, do not drill or punch
holes in base of unit. Leaking in roof may occur if
unit base is punctured.
from entering unit.
507348-04 12/2015