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NOTE - All economizer modes of operation will modulate 
dampers to 55 F (13 C) supply air.
F-Gravity Exhaust Dampers
  
and LAGEDH are used in horizontal air discharge appli-
cations. LAGEDH gravity exhaust dampers are installed 
in the return air plenum . The dampers must be used any 
time an economizer or power exhaust fans are applied to 
LGM series units. An exhaust hood is furnished with the 
gravity exhaust damper.
Gravity exhaust dampers allow exhaust air to be dis-
charged from the system when an economizer and/or 
power exhaust is operating. Gravity exhaust dampers also 
        
installation instructions for more detail.
LAPEF
POWER EXHAUST
FAN ASSEMBLY
LAGED GRAVITY
EXHAUST DAMPERS
ECONOMIZER
FRESH AIR
HOOD
P18
LAGED AND LAPEF INSTALLATION
FIGURE 31 
G-C1PWRE10 Power Exhaust Fans
       
applications only. C1PWRE10 fans require optional down-
      -
mizers. Power exhaust fans provide exhaust air pressure 
relief and also run when return air dampers are closed 
and supply air blowers are operating. Figure 31 shows 
the location of the power exhaust fans. See installation 
instructions for more detail.
Electric heater is available to automatically control the 
minimum temperature in the gas burner compartment. 
The kit includes the following parts:
1 -          
possible to the gas valve. The strip heater is rated 
at 500 Watts (line voltage).
2 -   A thermostat mounting box is installed on the 
vestibule of the heating compartment. Included in 
the box are the following thermostat switches:
a.  
which opens on a temperature drop. The switch is wired in 
series with 24v power and the combustion air blower switch. 
         
switch opens and the gas heat section is de-energized. The 
switch automatically resets when the heating compartment 
b.  
which opens on a temperature rise. The switch is wired in 
series with K125 coil. When the temperature rises above 
energized through K125. The switch automatically resets 
c.  
which closes on a temperature drop. The switch is wired in 
        
through K125. The switch automatically opens when heating