AAON RK Series - Manual (Page 7)

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recovery wheel will restore latent effectiveness to near
original performance.
To clean, gain access to the energy recovery wheel
and remove segments. Brush foreign material from the
face of the wheel. Wash the segments or small wheels
in a 5% solution of non-acid based coil cleaner or
alkaline detergent and warm water.
Soak in the solution until grease and tar deposits are
loosened (Note: some staining of the desiccant may
remain and is not harmful to performance). Before
removing, rapidly run finger across surface of segment
to separate polymer strips for better cleaning action.
Rinse dirty solution from segment and remove excess
water before reinstalling in wheel.
CAUTION !
Do Not use acid based cleaners, aromatic
solvents, steam or temperatures in excess of
170°F; damage to the wheel my occur!
Air Seals
Four adjustable diameter seals are provided on each
cassette to minimize transfer of air between the
counter flowing airstreams.
To adjust diameter seals, loosen diameter seal
adjusting screws and back seals away from wheel
surface. Rotate wheel clockwise until two opposing
spokes are hidden behind the bearing support beam.
Using a folded piece of paper as a feeler gauge,
position paper between the wheel surface and
diameter seals.
Adjust seals towards wheel surface until a slight
friction on the feeler gauge (paper) is detected when
gauge is moved along the length of the spoke.
Retighten adjusting screws and recheck clearance
with “feeler” gauge.
Wheel Drive Components
The wheel drive motor bearings are pre-lubricated
and no further lubrication is necessary.
The wheel drive pulley is secured to the drive motor
shaft by a combination of either a key or D slot and set
screw.
The set screw is secured with removable locktite to
prevent loosening. Annually confirm set screw is
secure. The wheel drive belt is a urethane stretch
belt designed to provide constant tension through the
life of the belt. No adjustment is required. Inspect the
drive belt annually for proper tracking and tension. A
properly tensioned belt will turn the wheel immediately
after power is applied with no visible slippage during
start-up.
INSTALLATION CONSIDERATIONS
AAONAIRE® Energy recovery cassettes are
incorporated within the design of packaged units,
packaged air handlers and energy recovery
ventilators. In each case, it is recommended that the
following considerations be addressed:
Accessibility
The cassette and all its operative parts; i.e.: motor,
belt, pulley, bearings, seals and energy transfer
segments must be accessible for service and
maintenance. This design requires that adequate
clearance be provided outside the enclosure.
Where cassettes are permanently installed in a
cabinet, access to both sides of the cassette must be
provided.
Orientation & Support
The Energy Recovery Cassette may be mounted in
any orientation. However, Care must be taken to
make certain that the cassette frame remains flat
and the bearing beams are not racked.
To verify, make certain that the distance between
wheel rim and bearing beam is the same at each end
of the bearing beam, to within 1/4 of an inch
(dimension A & B). This amount of racking can be
compensated for by adjusting the diameter seals.
If greater than 1/4 inch, racking must be corrected
to ensure that drive belt will not disengage from
wheel.
Avoid Racking Of Cassette Frame