Optional Energy Wheel - LG AR-DR12-05A Installation And Operation Manual

OPTIONAL ENERGY WHEEL

Start Up
If selected, the energy wheel is installed in the unit's airstream
with one half of the wheel in the intake airstream and one half in
the exhaust airstream. Air leakage between the two airstreams has
to be kept to a minimum and the wheel has air seals that must be
adjusted for that purpose. The seals must be adjusted at time of
start-up.
Drive Belt
Inspect the drive belt. Make sure the belt rides smoothly in the pul-
ley and around the outside of the wheel. Note the directional arrow
and data information shown in the image.
Adjust the Air Seals
Make sure the unit power supply is locked out. Disconnect the wiring
to the wheel module and pull the wheel cassette out of the cabinet
on its tracks. Large cassettes are not removable. Then slowly rotate
the wheel by hand to make sure there is no binding or misalignment.
There is a perimeter seal located around the outside of the wheel
and a diameter seal across the face of the wheel on both sides.
Check to make sure that all air seals are secure and in good condi-
tion.
Adjust the air seals by loosening all the air seal retaining screws on the bearing support. Using a piece of paper as a feeler gauge, adjust the
seals so they almost touch the face of the wheel while tugging slightly on the paper. When the wheel is rotated, there should be a slight tug
on the paper. Tighten the screws, repeat the steps on the other set of seals.
Push the wheel cassette back into the unit and plug in the power connector. Turn the main power supply back on and then observe the opera-
tion of the wheel by opening the wheel access door slightly. Remove filters if necessary to observe the wheel.
Sequence of Operation
Optional Economizer - The economizer will be locked out when: the outside air is below economizer lockout; the unit is operating in dehu-
midification mode; or there is a call for heating.
• Stop Wheel: When economizer mode is enabled and there is a signal for cooling, the wheel will stop rotating to allow free cooling.
• Modulate Wheel: When economizer mode is enabled and there is a signal for cooling, the wheel VFD modulates wheel speed to maintain
the discharge temperature set point.
Optional Frost Control - The microprocessor controller will output a signal when wheel frosting is occurring which is determined by a tempera-
ture set point (OA<5°F – 2°F hysteresis, adjustable) and wheel pressure drop increase.
• Preheat: When frosting is occurring, the preheater is energized to defrost the wheel. Once the pressure drop decreases below the set point,
the preheater is de-energized.
• Modulating Wheel: Includes a VFD in addition to the thermostat and pressure sensor. When modulating wheel frost control is initiated, the
VFD will reduce the speed of the wheel, which keeps the exhaust air condition from reaching saturation, thus, eliminating condensation and
frosting. If the outdoor air temperature is greater than the frost threshold temperature OR the pressure differential is less than the set point,
the wheel will run at full speed. If the outdoor air temperature is less than the frost threshold temperature AND the pressure differential is
greater than the set point, the wheel will run at reduced speed until the pressure differential falls below the set point. The temperature and
pressure differential set points are set at the factory, but are field-adjustable. The VFD will be fully programmed at the factory.
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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.
Figure 23: Optional Energy Wheel
Adjustable
Air Seals
Drive Belt
Retaining
Screws
Bearing
Support
Label showing
cassette serial
number and
date code
Drive
Pulley