Greenheck ERCH - Energy Recovery Unit with Packaged DX (468151) - Manual (Page 29)

29
Energy Recovery Unit with Packaged DX
Vibration
Excessive vibration may be experienced during initial start-up . Left unchecked, excessive vibration can cause
a multitude of problems, including structural and/or component failure . The most common sources of vibration
are listed below .
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 .
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 .
1 . Wheel Unbalance
2 . Drive Pulley Misalignment
3 . Incorrect Belt Tension
4 . Bearing Misalignment
5 . Mechanical Looseness
6 . Faulty Belts
7 . Drive Component Unbalance
8 . Poor Inlet/Outlet Conditions
9 . Foundation Stiffness
UNIT START-UP
R
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ta
tio
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R
o
ta
tio
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Rotation
Rotation
Backward Inclined
Forward Curved
Airflow
Airflow
R
o
ta
tio
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R
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Rotation
Rotation
Backward Inclined
Forward Curved
Airflow
Airflow
Coils
Leak test thermal system to insure tight connections . Check for properly trapped condensate drain .
Direction of Fan Wheel Rotation
Blower access is labeled on unit . 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
(see Rotation Direction figures) . 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 bearings . Refer to
the Troubleshooting section of this manual if a problem
develops .
Fan RPM
Supply fan and exhaust fan will have an adjustable motor
pulley (on 15 HP and below) preset at the factory to the
customer specified RPM . Fan speed can be increased or
decreased by adjusting the pitch diameter of the motor
pulley . Multi-groove variable pitch pulleys must be adjusted
an equal number of turns open or closed . Any increase
in fan speed represents a substantial increase in load on
the motor . Always check the motor amperage reading and
compare it to the amperage rating shown on the motor
nameplate when changing fan RPM . All access doors must
be installed except the control center door . Do not operate
units with access doors open or without proper ductwork
in place as the fan motors will overload.