Fan Shaft Bearing Removal - Carrier AERO 39MN Installation, Start-Up And Service Instructions Manual

4. The calibration is changed by moving the clamp. Loos-
en the clamp screw(s) and move slightly toward the he-
lix if gage is reading high; move away if gage is low.
Tighten clamp screw and install scale assembly.
5. Place cover and O-ring in position. Make sure the hex
shaft on inside of cover is properly engaged in zero ad-
just screw.
6. Secure cover in place by screwing bezel tightly. Note
that the area under the cover is pressurized in operation
and therefore gage will leak if not properly tightened.
7. Zero gage and compare to test instrument. Make further
adjustments as necessary.

Fan Shaft Bearing Removal

1. Isolate the unit from the system by closing dampers to
prevent "pin wheeling." Tie off the fan wheel to prevent
rotation.
2. Lock open and tag electrical disconnect.
3. Enter through fan section access door or remove panels
as required.
4. Loosen motor base to frame bolts. Adjust motor to re-
lease belt tension and remove belts. Do not stretch belts
over sheaves. Damage to belts can result.
5. Remove bolts on bushing of fan shaft sheave, insert
bolts in jacking hole provided on bushing and slowly
jack bushing from sheave. Remove bushing and sheave.
6. Loosen bearing holddown bolts, block shaft up.
7. Loosen bearing setscrews and locking collar, and re-
move holddown bolts.
NOTE: To facilitate easy removal of setscrew fastened
wheels, sheaves, or bearings, remove the setscrew com-
pletely. Taking care not to damage threads, insert a flat ended
drift or punch, tap lightly and carefully return the material
displaced on the shaft by the setscrew to its original place.
8. Remove bearing while observing the following precau-
tions:
a. Make certain fan shaft surface is not rough or
scored. If so, clean up surface with fine emery cloth.
b. Add a few drops of oil after cleanup of shaft end.
It should not be necessary to drive a new bearing onto
shaft. If light tapping is needed, do not tap against outer
race. Equipment damage may result.
9. Check fan shaft diameter at bearing mount. If worn by
more than 0.001-in. below nominal, shaft should be re-
placed.
10. Install new bearing, tighten holddown bolts, and then
tighten bearing locking collar or setscrews.
11. Make certain fan wheel does not rub sides of fan hous-
ing after installing new bearings.
12. Recoat fan shaft with a rust inhibitor or grease.
13. Replace sheave and belts. Adjust and align as described
in Installation, Sheaves and V-Belts sections.
14. Replace access panels.
15. Restore electrical power.
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CAUTION