TO INCREASE CFM
LOOSEN ALLEN SCREW &
TURN PULLEY CLOCKWISE
TO DECREASE CFM
TURN PULLEY
COUNTERCLOCKWISE
BLOWER
ASSEMBLY
SLIDING BASE
LOOSEN (4) SCREWS TO
ADJUST BELT TENSION
SIDE VIEW
MOTOR
ALLEN
SCREW
PULLEY
INSTALLATIONS WITH DUCTWORK
ROOFTOP UNIT
SUPPLY
TURN
MAIN
DUCT RUN
D-Blower Belt Adjustment
Maximum life and wear can be obtained from belts only if
proper pulley alignment and belt tension are maintained.
Tension new belts after a 24-48 hour period of operation.
This will allow belt to stretch and seat into pulley grooves.
Make sure blower and motor pulley are aligned. See figure
15 for blowers not equipped with a tensioner and figure 16
for units equipped with an optional belt tensioner.
Blowers Without Belt Tensioner
1- Loosen four screws securing blower motor to sliding
base. See figure 13.
LGH/LCH156, 180, 210, 240, 300S
BLOWER ASSEMBLY - NO TENSIONER
BELT TENSION
ADJUSTING
BLOWER
MOTOR
LOCATION OF STATIC PRESSURE READINGS
RETURN AIR
READING LOCATION
RE
FIRST BRANCH
OFF OF MAIN RUN
SUPPLY AIR
READING
LOCATION
TO INCREASE BELT TENSION
1-Loosen four screws securing blower motor to
2-Turn adjusting screw to the left, or counter
3-Tighten four screws.
SCREW
FIGURE 13
INSTALLATIONS WITH CEILING DIFFUSERS
ROOFTOP UNIT
SUPPLY AIR
READING
LOCATION
FIGURE 14
2- To increase belt tension -
Turn belt tension adjusting screw to the left, or
counterclockwise, to tighten the belt. This increases
the distance between the blower motor and the
blower housing.
To loosen belt tension -
Turn the adjusting screw to the right, or clockwise to
loosen belt tension.
3- Tighten four screws securing blower motor to sliding
base once adjustments have been made.
Page 14
sliding base.
clockwise, to move the motor downward and
tighten the belt.
BLOWER
WHEEL
PULLEY
REMOVE SCREWS TO
SLIDE BLOWER
ASSEMBLY OUT OF UNIT
RE
SUPPLY
TURN
DIFFUSER
RETURN AIR
READING
LOCATION