Krueger | 1401 N Plano Rd | Richardson, TX 75081 | 972.680.9136 | [email protected] | www.krueger-hvac.com
KAH Operation & Maintenance Guide
Page: 20 of 88
Thermotech®
Start-Up Procedure
1. Remove the belts from the motor sheave and rotate
the wheel a minimum of one full Revolution. The seals
are non-contact. If the wheel does not rotate freely it
may be due to the wheel being in contact with the
seal. If the wheel cannot be turned by hand contact
Thermotech. Note: For TC sizes 14-82. To remove
the belt an idler pulley will need to be loosened.
2. The side seals should also be checked for clearance
to insure nothing has moved in shipping. If the wheel
is in contact with the aluminum encasing the side
seals, the wheel will need to be re-centered in the
casing. This is done by loosening the bearing bolts
and by using the bearing adjusting bolts. Re-center
the wheel insuring proper side seal clearance. Re-
tighten bearing bolts as follows:
3/8” = 35 ft lbs.
1/2” = 45 ft. lbs.
3/4” = 100 ft lbs.
3. Check to insure sheave/bushing is not rubbing on the
gear box.
4. At this point the wheel should rotate freely with no
drag or rubbing, with the exception of the rivets at
the hub cover. A slight rub here is acceptable. Proper
wheel rotation technique:
Rotate wheel by applying pressure to the rim not
the media. Care should be taken not to damage the
media face.
5. The seals are set at the factory and should not require
adjustment. If the seals are rubbing on the media
face, due to installation or other factors, the seals will
need to be adjusted. First, rotate the wheel one full
revolution and determine where the wheel media face
is rubbing on the seal. Working on one seal quadrant
at a time, loosen the seal tek screws. Then, move
the seal away from the wheel surface until no more
rubbing is noticed. A typical large diameter wheel
will have a flatness variation of 1/16” from the high
to the low point of the wheel surface. If the seals are
adjusted correctly, the seal gap will vary that much as
the wheel turns, but it should never be touching the
wheel surface.
6. If the unit is supplied with an adjustable purge,
determine the proper purge angle from the ordering
code on the unit nameplate or the specific data for
your project. Insure proper purge angle setting is
correct by visual inspection. The minimum purge
angle is 1 degree. There are 10 adjustment points in
one degree increments.
SECTION 2 - START-UP & OPERATION (CONTINUED)
Purge Adjustment: TF Series Wheels
The purge angle can be adjusted with each purge
setting hole equal to one degree. The bolts that
position the purge angle are located on the backside
of the purge and are not visible. First loosen bolt 2
and 3. Then remove the bolt 1. The whole purge
section is then movable to a new location. Reinstall
bolt 1 in the new hole location and re-tighten all the
bolts.
Purge Adjustment: TC Series Wheels
The purge angle can be adjusted with each purge
setting hole equal to one degree. Bolt number 1
positions the purge angle and is located on the front
side of the purge. Bolt number 2 is the pivot point and
is located on the inside of the frame and is not visible.
First loosen bolt 2. Then remove bolt 1. The purge
wiper section is then movable to a new location. Re-
install bolt 1 in the new hole location and re-tighten
all the bolts.
Purge angle detail showing bolt locations on front
side of purge. The purge wiper bolt 2 pivot point is
slotted so as the purge wiper is adjusted it can be
moved so that the outer edge of the seal is always in
contact with the main rotor seal.
7. Grease bearings using Dow Corning Molykote BR2-
plus Lithium based high pressure grease. Apply the
grease to the fitting while turning wheel until a slight
amount of grease is purged. Remove visible grease
residue from the bearing. The bearings are filled with
grease prior to shipment. This step may be required if
the units have been idle on the job site for more than
6 months. Put belts back on pulley.
8. If the unit is provided with a VFD, verify the motor is
wired for the correct voltage provided by the VFD.