48
Fan Powered Terminal Units IOM
TROUBLESHOOTING
To remove the fan motor and wheel:
1. Disconnect motor wiring. Note connections.
2. The fan motor and wheel assembly is attached to the
discharge panel with 4 hex nuts.
3. Remove the motor by removing the 3 screws that attach
the torsion flex or belly band mounts to the inlet ring.
4. Remove wheel by unscrewing the hub set screws that are
accessed through the open end of the wheel.
FAN MOTOR WIRING
Refer to the fan motor wiring details shown on the wiring
diagram attached to the unit. Failure to reconnect the fan
properly can cause damage to the motor and/or serious
personal injury.
FAN MOTOR MAINTENANCE
Unit motors are equipped with permanently lubricated
bearings. Inspect fan and motor assembly for accumulation
of dust and dirt as required by operating environment. Clean
as necessary.
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
energized.
IF FAN MOTOR RUNS, EXCESSIVE NOISE:
1. Make sure the blower, and all components have no
clearance 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:
4.
Check for ductwork restrictions, dirty air filters, and
clogged water coils.
5.
Re-adjust fan speed control.
6. Discharge static pressure too high.
IF REPAIR OR REPLACEMENT IS REQUIRED:
1. Motor and fan should be removed as an assembly.
Disconnect 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
assembly. 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
assembly.
NOTE: Over-tightening motor mounting screws may
crush isolation bushings, and cause excessive fan noise
and wear.
Summary of Contents for KLPP
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