Greenheck Centrifugal (CSW, BIDW, AFDW), Industrial (IPA, IPO, IPW) and Filtered Supply (LSF) (463687) - Manual (Page 7)

7 Centrifugal, Industrial and Filtered Supply
Unit Start-Up
1. Disconnect and lock-out all power switches to fan.
See warning below.
2. Check all fasteners, set screws and locking
collars on the fan, bearings, drive, motor base and
accessories for tightness.
3. Rotate the fan wheel by hand and assure no parts
are rubbing.
4. Check for bearing alignment and lubrication.
5. Check for coupling alignment (Arr. 8 only).
6. Check the V-belt drive for proper alignment and
tension.
7. Check all guarding (if supplied) for being securely
attached and not interfering with rotating parts.
8. Check operation of variable inlet vanes or
discharge dampers (if supplied) for freedom of
movement.
9. Check all electrical connections for proper
attachment.
10. Check housing and ductwork, if accessible,
for obstructions and foreign material that may
damage the fan wheel.
Additional Steps for Initial Start-Up
1. Check for proper wheel rotation by momentarily
energizing the fan. Rotation is always determined
by viewing the wheel from the drive side and
should correspond to the rotation decal affixed to
the unit. One of the most frequently encountered
problems with centrifugal fans is motors which
are wired to run in the wrong direction. This is
especially true with 3-phase installations where
the motor will run in either direction, depending
on how it has been wired. To reverse rotation
of a 3-phase motor, interchange any two of the
three electrical leads. Single phase motors can
be reversed by changing internal connections as
described on the motor label or wiring diagram.
Vibration
Excessive vibration is the most frequent problem
experienced during initial start-up.
Left unchecked, excessive vibration can cause a
multitude of problems, including structural and/or
component failure.
Many of these conditions can be discovered by careful
observation. Refer to the troubleshooting section
of this manual for corrective actions. If observation
cannot locate the source of vibration, a qualified
technician using vibration analysis equipment should
be consulted. If the problem is wheel unbalance, in-
place balancing can be done providing there is access
to the fan wheel. Any correction weights added to
the wheel should be welded to either the wheel back
(single-plane balance) or to the wheel back and wheel
cone (two-plane balance).
Greenheck performs a vibration test on all centrifugal
fans before shipping. Three vibration readings are
taken on each bearing in the horizontal, vertical, and
axial directions. The allowable maximum vibration for
belt drive units is 0.15 in/sec. peak (0.08 in/sec. direct
drive) velocity filter-in for rigid mount and 0.20 in/sec.
peak velocity filter-in for flexible mount at the fan RPM
per AMCA Standard 204. These vibration signatures
are a permanent record of how the fan left the factory
and are available upon request.
Generally, fan vibration and noise is transmitted
to other parts of the building by the ductwork. To
eliminate this undesirable effect, the use of heavy
canvas connectors is recommended. If fireproof
material is required, Flexweave™1000 - Type FN-30
can be used.
Common Sources of Vibration
1. Wheel Unbalance
2. Drive Pulley Misalignment
3. Incorrect Belt Tension
4. Bearing / Coupling Misalignment
5. Mechanical Looseness
6. Faulty Belts
7. Drive Component Unbalance
8. Poor Inlet/Outlet Conditions
9. Foundation Stiffness
WARNING
Disconnect and secure to the “Off” position all
electrical power to the fan prior to inspection
or servicing. Failure to comply with this safety
precaution could result in serious injury or death.
2. If the fan has inlet vanes, they should be partially
closed to reduce power requirements. This is
especially important if the fan is designed for a
high temperature application and is being started
at room temperature.
3. Fans with multi-speed motors should be checked
on low speed during initial start-up.
4. Check for unusual noise, vibration or overheating
of bearings. Refer to the “Troubleshooting” section
of this manual if a problem develops.
5. Grease may be forced out of the bearing seals
during initial start-up. This is a normal self-purging
feature of this type of bearing.
Centrifugal
Backward Inclined
Centrifugal
Airfoil
Industrial Process
Radial Blade
Always viewed from the drive side.
Clockwise Rotation