Start Up Components - LG AR-DR12-05A Installation And Operation Manual

Fan
The fan should be checked for free rotation. If any binding occurs,
check for concealed damage and foreign objects in the fan housing.
When operating conditions of the fan are to be changed
(speed, pressure, temperature, etc.), consult manufacturer
to determine if the unit can operate safely at the new condi-
tions.
Supply Fan (Plenum Type)
The unit contains one or two plenum supply fans located on the end
of the unit opposite the outdoor air intake and may optionally have
a relief air blower which is referred to as an exhaust blower in this
document. Efficient fan performance can be maintained by having
the correct offset.
Offset
Proper offset, or overlap, is adjusted by loosening the wheel hub
from the shaft and moving the wheel to the desired position along
the shaft. The transition between the inlet cone and the wheel should
be as shown; there is a smooth feel to the profile when moving one
component to the other
Refer to the respective Installation, Operation and Maintenance
Manual shipped with this unit for additional start-up and maintenance
information regarding the plenum fan.
Fan Wheel Rotation Direction
Check for proper wheel rotation by momentarily energizing the fan. Rotation is determined by viewing the wheel from the drive side and
should match the rotation decal affixed to the fan housing. If the wheel is rotating the wrong way, direction can be reversed by interchanging
any two of the three electrical leads. Check for unusual noise, vibration or overheating of the bearings. Refer to the Troubleshooting portion
of this manual if a problem develops.
Supply/Exhaust Fan
The optional exhaust fan is a direct-drive plenum type. Fan speed is controlled by a VFD which, in turn, is controlled by the microproces-
sor controller or by an external signal. Motor speed will be set on the VFD during the unit Test and Balance, but after that, the VFD will not
normally be changed. Always check the motor amperage rating shown on the motor nameplate when changing the fan RPM. All access doors
must be installed except the control center door.
Vibration
Excessive vibration may be experienced during initial start-up. Left unchecked, excessive vibration can cause a multitude of problems includ-
ing structural and/or component failure. The most common sources of vibration are:
• Off axis or loose components
• Drive component unbalance
• Poor inlet/outlet conditions
• Foundation stiffness
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.
Generally, fan vibration and noise is transmitted to other parts of the building by the ductwork. To eliminate this undesirable effect, the use of
flexible connectors is recommended.
Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. "LG" is a registered trademark of LG Corp.

START UP COMPONENTS

Fan Size
ER35C
ER45C
ER50C
ER56C
Offset Tolerance
(inches) (inches)
5/32 ± 1/32
3/16 ± 1/32
13/64 ± 1/32
1/4 ± 1/32
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