Greenheck Fan HEAT RECOVERY UNIT WITH EVAPORATIVE COOLING HRE-20 - Manual (Page 34)

34
UNIT START-UP
Energy Recovery Wheel
The HRE models contain a sensible energy recovery wheel . The
wheels are inspected for proper mechanical operation at the
factory . However, during shipping and handling, shifting can occur
that may affect wheel operation . The wheel is accessible through
the access door marked “Energy Wheel Cassette Access” . For
the HRE-20 AND HRE-45 models, the wheel cassette slides out.
Due to the size and weight of the HRE-55 AND HRE-90 wheels,
they remain stationary and all maintenance is performed in place .
There is 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 .
Check that the air seals located around the outside
of the wheel and across the center (both sides of
wheel) are secure and in good condition . Air seal
clearance is determined by placing a sheet of
paper, to act as a feeler gauge, against the wheel
face . To access seals, enter unit for HRE-55 &
HRE-90, or pull out the cassette for HRE-20 & HRE-
45, following the instructions in Energy Recovery
Wheel Maintenance section .
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 .
Tighten the screws so the air seals tug slightly on the sheet of paper .
Replace cassette into unit, plug in wheel drive, replace access door and apply power . Observe by opening door
slightly (remove filters if necessary to view wheel) that the wheel rotates freely at about 35 RPM .
Drive Belt
Drive Pulley
Adjustable
Air Seals
Label showing
cassette serial #
and date code
Bearing Support
Inside layout of HRE unit