Operation / Adjustment; Blower Assembly - Lennox KGA Series Service Literature

C-Blower Compartment
The blower compartment in all KGA092/150S units is located
between the evaporator coil and the condenser coil section.
The blower assembly is accessed by disconnecting the blow­
er motor .See Blower Access in the Operation/ Adjustment
section. The blower pulls out as shown in figure 7.
1-Blower Wheels
All KGA092/150 units have one 15 in. x 15 in. (381 mm x 381
mm) blower wheel.
2-Indoor Blower Motor B3
All units use three‐phase single‐speed blower motors. CFM
adjustments are made by adjusting the motor pulley (sheave).
Motors are equipped with sealed ball bearings. All motor speci­
fications are listed in the SPECIFICATIONS(table of contents)
in the front of this manual. Units may be equipped with motors
manufactured by various manufacturers, therefore electrical
FLA and LRA specifications will vary. See unit rating plate for
information specific to your unit.

OPERATION / ADJUSTMENT

Blower Operation
Initiate blower demand at thermostat according to instruc­
TO INCREASE BELT TENSION
1- Loosen four bolts securing motor mounting base
to frame.
2- Turn adjusting bolt to the right, or clockwise, to
move the motor away from the blower housing.
IMPORTANT - Gap between end of frame and motor
mounting base should be equal at both ends, i.e. par­
allel along gap.
3- Tighten four bolts securing motor mounting base
to frame.
4- Relieve tension on two adjusting bolts.
BELT ADJUSTING BOLTS
- TURN CLOCKWISE
TO TIGHTEN BELT
GAP BETWEEN
EDGES SHOULD BE
PARALLEL ON BOTH
ENDS BEFORE
TIGHTENING MOTOR
MOUNTING BASE IN
PLACE
REMOVE TWO SCREWS
TO COMPLETELY SLIDE
BLOWER OUT OF UNIT

BLOWER ASSEMBLY

MOTOR MOUNTING
BASE
MOTOR
REMOVE TWO SCREWS ON EACH
SIDE TO SLIDE FRAME PARTIALLY
OUT OF UNIT FOR SERVICE ACCESS
tions provided with thermostat. Unit will cycle on thermostat
demand. The following steps apply to applications using a
typical electro-mechanical thermostat.
1- Blower operation is manually set at the thermostat sub­
base fan switch. With fan switch in ON position, blow­
ers will operate continuously.
2- With fan switch in AUTO position, the blowers will cycle
with demand. Blowers and entire unit will be off when
system switch is in OFF position.
Determining Unit CFM
1- The following measurements must be made with a dry
indoor coil. Run blower without a cooling demand.
Measure the indoor blower shaft RPM. Air filters must
be in place when measurements are taken.
2- With all access panels in place, measure static pres­
sure external to unit (from supply to return). Measure
static below roof curb if roof curb is used.
3- Refer to blower tables in BLOWER DATA (table of con­
tents) in the front of this manual. Use static pressure and
RPM readings to determine unit air volume.
BLOWER
HOUSING
LOOSEN BEFORE
ADJUSTING BELT TENSION
(TWO EACH SIDE)
FIGURE 7
Page 18
SIDE VIEW
MOTOR
ALLEN
SCREW
PULLEY
BLOWER
FRAME