ELECTRICAL CONNECTIONS:
All electrical work must be done by a qualified electrician according to local, state and
national codes. Be sure that the designated circuit breaker is off until all wiring has been
completed.
NOTE: It is recommended that a properly sized motor starter and overload protector be used in the
supply circuit of the 3 Phase motor. The 120V units have thermally protected motors with on/off
switches.
1. Make electrical connections as shown in the wiring diagram to the wires protruding from the
conduit on the side of the unit.
2. Check blower for proper rotation direction. Blower should rotate clockwise when viewed from the
pulley end. If the blower rotates backwards, interchange two of the motor supply connections.
3. Check current draw of the motor. Do not exceed Amps specified.
PRE-OPERATING CHECKLIST:
Check blower drive belt for proper tension. Belt should deflect ¾” when firm pressure is applied
midway between the pulleys.
Check that motor, blower and drive pulleys are mounted securely.
Make sure that both corners of every pocket in the filter bag is supported by the filter support rods
and that filter support rods are fully engaged in their support brackets.
Air flow direction arrows on the pre-filters must point toward the blower.
Make sure all access panels removed during the installation are re-installed and the filter access
door is closed.
GENERAL MAINTENANCE:
Occasionally check the condition of the drive belt for tightness and wear.
Check the bower bearings for unusual wear and the blower wheel for debris and dirt. Clean when
necessary.
Check the wiring for loose connections or for cracked insulation.
No lubrication is required for the motor because it is a permanent pre-lube design. Excessive
dirt/oil should be periodically removed.
PRESSURE SWITCH ADJUSTMENT:
1. The pressure switch which turns the light on with a differential pressure increase, should be wired
to poles L1 (red) and L2 (blue) at the time of installation with 230/460 volt source (See Wiring
Diagram).
2. The pressure switch is preset at the factory to indicate (light on) dirty filters, but may need
readjustment due to a desire for earlier or later filter changes, a different combination of filters, or
because the set point shifted during shipping. The pressure switch is also orientation sensitive. To
re-adjust the switch, remove the hole plug in the side of the unit for access to the adjustment
screw. Make sure filters and pre-filters are installed in unit. Turn the unit on and place a piece of
cardboard over the intake covering about 80% to 85% of the intake area. With a standard
