Lennox KHA SERIES, Manual

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Page 35
VI−ACCESSORIES
The accessories section describes the application of most of
the optional accessories which can be factory or field installed
to the KHA units.
A−T1CURB
When installing the KHA units on a combustible surface for
downflow discharge applications, the Lennox T1CURB 8
inch, 14-inch, 18 inch or 24-inch height roof mounting frame
is used. The roof mounting frames are recommended in all
other applications but not required. If the units are not
mounted on a flat (roof) surface, they MUST be supported
under all edges and under the middle of the unit to prevent
sagging. The units MUST be mounted level within 1/16" per
linear foot or 5mm per meter in any direction.
The assembled mounting frame is shown in figure 15. Re-
fer to the roof mounting frame installation instructions for
details of proper assembly and mounting. The roof mount-
ing frame MUST be squared to the roof and level before
mounting. Plenum system MUST be installed before the
unit is set on the mounting frame. Typical roof curbing and
flashing is shown in figure 16. Refer to the roof mounting
frame installation instructions for proper plenum construc-
tion and attachment.
FIGURE 15
ASSEMBLED ROOF MOUNTING FRAME
FIGURE 16
ROOF
MOUNTING FRAME
(Extends around entire
perimeter of unit)
FIBERGLASS
INSULATION
(Furnished)
COUNTER FLASHING
(Field Supplied)
UNIT BASE
BOTTOM
RIGID INSULATION
(Field Supplied)
ROOFING
MATERIAL
CANT STRIP
(Field Supplied)
NAILER STRIP
(Furnished)
UNIT BASE
RAIL
TYPICAL FLASHING DETAIL
B−Transitions
Optional supply/return transitions T1TRAN10AN1 is
available for use with the KHA 2, 2.5, 3, 4 and 5 units uti-
lizing optional T1CURB roof mounting frames. Transi-
tion must be installed in the mounting frame before
mounting the unit to the frame. Refer to the manufacturer’s
instructions included with the transition for detailed installa-
tion procedures.
C−Outdoor Air Dampers
T1DAMP11A−1 is available for KHA024, 030 036, 048 units
and T1DAMP11N−1 is available for the KHA060S. Both
sets include the outdoor air hood. A motorized kit
(T1DAMP21AN1) can be ordered separately for all KHA
unit sizes. The dampers may be manually or motor (M) op-
erated to allow up to 25 percent outside air into the system
at all times (see figure 17). Washable filter supplied with
the outdoor air dampers can be cleaned with water and a
mild detergent. It should be sprayed with Filter Handicoat-
er when dry prior to reinstallation. Filter Handicoater is R.P.
Products coating no. 418 and is available as Lennox Part
No. P−8−5069.