Transitions; Supply And Return Diffusers; Laoad(M) Outdoor Air Dampers; Laremd Economizers - Lennox LGA Series Unit Information

B−Transitions
Optional supply/return transitions LASRT30/36 are
available for use with LGA/LGC/LCA/LCC series units
utilizing optional LARMF18/36 roof mounting frame.
Transition must be installed in the LARMF18/36 mount-
ing frame before mounting the unit to the frame. Refer to
the manufacturer's instructions included with the transition
for detailed installation procedures.
C−Supply and Return Diffusers
Optional flush mount diffuser/return FD11 and extended
mount diffuser/return RTD11 are available for use with the
LGA/LGC/LCA/LCC units. Refer to manufacturer's instruc-
tions included with transition for detailed installation
procedures.
D−LAOAD(M) 30/36Outdoor Air Dampers
LAOAD(M)30/36 consists of a set of dampers which may be
manually or motor (M) operated to allow up to 25 percent
outside air into the system at all times (see figure 37). Either air
damper can be installed in LGA/LGC/LCA/LCC units. Wash-
able filter supplied with the outdoor air dampers can be
cleaned with water and a mild detergent.It should be
sprayed with Filter Handicoater when dry prior to reinstalla-
tion. Filter Handicoater is R.P. Products coating no. 418 and is
available as Lennox Part No. P−8−5069.
E−LAREMD30/36 Economizer
(Field or Factory Installed)
The optional LAREMD30/36 economizer can be used
with LGA/LGC/LCA/LCC units in downflow and horizontal air
discharge applications. The LAREMD30/36 economizer uses
outdoor air for free cooling when temperature and/or humidity
is suitable. An economizer hood is required and must be or-
dered separately.
NOTE − Gravity exhaust dampers are required with power
exhaust.
The economizer is controlled by the economizer control
module A56 which connects to the main control module
A55. Both boards are part of the Integrated Modular Control
(IMC) which controls L" series unit operation.
The economizer will operate in one of four modes. Each
mode requires a different EM1 economizer DIP switch set-
ting. Each mode also requires different sensors.
LAOAD 30/36 MANUAL OUTDOOR AIR DAMPER
LAOAD(M) MOTORIZED OUTDOOR AIR DAMPER
FILTER BRACKET SIDE VIEW
Page 61
HOOD TOP SEAL
HOOD TOP
FILTER
FIGURE 37