Lennox KGA Series Service Literature page 33

E-K1ECON20B Economizer
(Field- or Factory-Installed)
Economizers use outdoor air for free cooling when temper­
ature and/or humidity is suitable. See figure 26.
The mixed air temperature sensor (R1) measures the sup­
ply air sensible temperature. See figure 27. The outdoor air
sensible control is the default economizer control. An out­
door air single sensible sensor, S175, is also provided. See
table 14 for outdoor and return air (OA and RA) sensor op­
tions. Refer to instructions provided with sensors for instal­
lation.
An IAQ sensor is used when demand control ventilation
(DCV) is specified. Damper minimum position can be set
lower than traditional minimum air requirements resulting in
cost savings. The IAQ sensor allows the A6 to open
dampers to traditional ventilation requirements as room oc­
) increases.
cupancy (CO
2
TABLE 14
Sensors
OA temperature (S175) is lower
Single OA Sensible
than free cooling setpoint.
OA temperature and humidity (A7)
Single OA Sensible
is lower than free cooling setpoint.
OA temperature and humidity (A7)
Differential Enthalpy -
is lower than RA temperature and
1 in OA and 1 in RA
humidity (A62).
CO
IAQ Sensor
CO
ECONOMIZER
Dampers will modulate to 55°F
discharge air (RT6) when:
sensed (A63 ) is higher than
2
setpoint.
2
ECONOMIZER
FIGURE 26
MIXED AIR SENSOR (R1) LOCATION
R1 MIXED
AIR SENSOR
Page 33
ACCESSORY
PANEL MULLION
DIVIDER PANEL
(Attach with two
provided screws)
BOTTOM OF
COMPRESSOR
SECTION
FLANGED
RETURN AIR
OPENING
FIGURE 27