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57
Fan Shaft Bearing Removal
1. Lock open and tag electrical disconnect.
2. Enter through fan section access door or remove panels as
required.
3. Place plywood or other rigid covering on floor to protect
insulation from damage.
4. Block wheel so that it will not pinwheel due to natural draft
through the unit.
5. Loosen motor base to frame bolts. Adjust motor to release
belt tension so removal of belts is done without stretching.
Do
not stretch belts over sheaves. Damage to belt can result.
6. Remove bolts on bushing of fan shaft sheave, insert bolts in
jacking hole provided on bushing and slowly jack bushing
from sheave. Then remove bushing on sheave.
7. Loosen bearing setscrews and locking collar.
8. Remove bearing holddown bolts.
9. Remove bearing while observing the following precautions:
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.
10. Check fan shaft diameter at bearing mount. If worn by more
than .001 in. below nominal, shaft should be replaced.
11. Install new bearing, tighten holddown bolts and then tighten
bearing locking collar and setscrews.
12. Make certain fan wheel does not rub sides of fan housing
after installing new bearings.
13. Recoat fan shaft with a rust inhibitor or grease.
14. Replace sheave and belts. Adjust and align as described in
Installation sections on installing sheaves and V-belts.
15. Remove insulation protection.
16. Replace access panels.
17. Restore electrical power.
CAUTION
It should not be necessary to drive a new bearing onto shaft. If
light tapping is needed, do not tap against outer race.
Table 18 — Filter Data
39L UNIT SIZE
03
06
08
10
12
15
18
21
25
Angle Filter Section
Filter
QtySize
(in.)
2…16x25
4…16x20
2…16x20
2…16x25
4…16x25
6…16x20
9…16x20
12…16x20
4…16x20
8…16x25
4…16x20
8…16x25
Nominal Face Area (sq ft)
5.56
8.89
10.00
11.11
13.33
20.00
26.67
31.11
31.11
Filter Mixing Box Section
Filter
QtySize
(in.)
2…16x25
4…16x20
2…16x20
2…16x25
4…16x25
6…16x20
9…16x20
9…16x20
3…16x20
6…16x25
4…16x20
8…16x25
Nominal Face Area (sq ft)
5.56
8.89
10.00
11.11
13.33
20.00
20.00
23.33
31.11
Flat Filter Section
Filter
QtySize
(in.)
2…16x16
2…20x20
2…20x25
2…16x25
1…20x25
3…20x25
6…16x20
3…16x20
3…20x20
3…20x25
3…16x25
2…16x20
2…20x20
2…20x25
2…16x25
Nominal Face Area (sq ft)
3.56
5.56
6.94
9.03
10.42
13.33
15.00
18.75
22.50