Vibration; Energy Recovery Wheel - Greenheck APEX-200 Installation, Operation & Maintenance Manual

Vibration

Excessive vibration maybe 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.
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

Energy Recovery Wheel

The APEX contains two energy recovery wheels (see
FIGURES 20 & 21). These wheels are inspected for
proper mechanical operation at the factory. However,
during shipping and handling, shifting can occur that may
affect wheel operation. Wheels are accessible through the
access doors marked "Energy Wheel Cassette Access".
Due to the size and weight of these wheels, they remain
stationary and all maintenance is performed in place.
There is ample room inside the unit to perform energy
recovery wheel servicing.
Turn the energy recovery wheels by hand to verify free
operation. The wheel should rotate smoothly and should
not wobble.
Drive Belt
Inspect the drive belt. Make sure the belt rides smoothly through the pulley and over the wheel rim.
Air Seals
Air seals are located around the perimeter of the
wheel and across the face of the wheel (both sides of
wheel). Check that these seals are secure and in
good condition.
Air seals which are too tight will prevent proper
rotation of the energy recovery wheel. Air seal
clearance may be checked by placing a sheet of
paper, to act as a feeler gauge, against the wheel
face. To adjust the air seals, loosen all eight seal
retaining screws. These screws are located on the
bearing support that spans the length of the cassette
through the wheel center. These seals are located on
each side of the wheel; be sure to check both of
them. Adjust the seals such that they tug slightly on
the sheet of paper as the wheel is turned. Tighten the
retaining screws.
Replace access doors and apply power. Observe that
the wheels rotate freely at about 60 RPM. If wheels
do not rotate or are binding, contact your local
representative.
Unit Start-Up
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.
Adjustable
Air Seals
17
FIGURE 20: Inside layout of APEX unit
Drive Belt
Drive Pulley
FIGURE 21: Energy recovery wheel components
Bearing Support
Label showing
cassette serial #
and date code
®