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VII−ACCESSORIES
The accessories section describes the application of most of
the optional accessories which can be installed to the TGA
units.
A−LARMF and LARMFH Mounting Frames
When installing either the TCA units on a combustible surface
for downflow discharge applications, the LARMF18/36 14-inch
or 24-inch (356 mm or 610mm) height roof mounting frame is
used. For horizontal discharge applications, use
LARMFH18/24 26-inch or 37-inch (660mm or 940mm) height
roof mounting frame. This frame converts unit from down-flow
to horizontal air flow. The 37 inch (940mm) horizontal frame
meets National Roofing Code requirements. The roof mount-
ing frames are recommended in all other applications but not
required. If the TCA units are not mounted on a flat (roof) sur-
face, 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 LARMF18/36 mounting frame is shown in fig-
ure 21. Refer to the roof mounting frame installation instruc-
tions for details of proper assembly and mounting. The roof
mounting 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 22. Refer to the roof mounting frame installa-
tion instructions for proper plenum construction and attach-
ment.
FIGURE 21
ASSEMBLED ROOF MOUNTING FRAME
FRONT
END
END
BACK
CENTER SUPPORTS
(TWO PIECES EACH)
FIGURE 22
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 LASRT18/24 are
available for use with TCA series units utilizing optional
LARMF18/36 roof mounting frame. Transition must be
installed in the LARMF18/36 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−Supply and Return Diffusers (all units)
Optional flush mount diffuser/return FD11 and extended
mount diffuser/return RTD11 are available for use with all TCA
units. Refer to manufacturer’s instructions included with
transition for detailed installation procedures.
D−T1ECON
Unit may contain an optional modulating economizer
equipped with an A6 enthalpy control and an A7 outdoor
enthalpy sensor. The economizer modulates to use out-
door air for free cooling when temperature is suitable.
The A6 enthalpy control is located in the economizer ac-
cess area. See figure 23. The A7 enthalpy sensor is located
on the division panel between horizontal supply and return
air sections.
