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If fan motor does not run:
1. Make sure that there is free rotation of blower wheel.
2. Remove fan packing.
3. Verify that there is no freight or installation damage.
4. Check for proper unit power.
5. Disconnects should be on, and check optional fusing.
6. Check for proper control signal, pie switch setting, proper
air control 24 vac at fan contactor, and that the coil is ener-
gized.
If fan motor runs, excessive noise:
1. Make sure the blower, and all components have no clear-
ance problems and are securely attached.
2. Verify the integrity of ductwork, make sure there are no
leaks or loose connections rattling diffusers or balancing
dampers.
3. Confirm that the maximum CFM not too high, or discharge
static pressure is too low.
If fan motor runs, insufficient airflow:
1. Check for ductwork restrictions, dirty air filters, and
clogged water coils.
2. Re-adjust fan speed control.
3. Discharge static pressure too high.
If repair or replacement is required:
1. Motor and fan should be removed as an assembly. Discon-
nect all power before servicing.
2. Remove the four hex nuts from the mounting lugs holding
the fan assembly to the discharge panel, and lower the as-
sembly.
NOTE: Do not allow assembly to hang from wiring.
3. Loosen the setscrew if removing motor from blower.
4. Hold the blower wheel to the motor shaft. Remove the
three screws holding motor to the fan housing, and slide
motor and fan housing apart. Reverse the procedure for as-
sembly.
NOTE: Overtightening motor mounting screws may crush isola-
tion bushings, and cause excessive fan noise and wear.