Carrier 39LA-25 Installation, Start-Up And Service Instructions Manual page 59

Fan and Shaft Removal
The fan wheel and shaft may be removed through inlet side of fan
housing. See Fig. 60.
1. Remove drive belts as described in Fan Shaft Bearing
Removal on page 57.
2. Block up fan wheel within housing to prevent dropping when
bearing bolts are removed.
3. Loosen and remove bearing holddown bolts.
4. Remove bearing support channels and inlet ring from one
side.
5. Remove fan shaft and fan wheel from unit.
6. Remove fan shaft from fan wheel.
7. Replace shaft and wheel into fan in the reverse order of their
removal.
8. Inspect bearings and if serviceable, replace on shaft.
9. Align fan wheel and shaft assembly in fan scroll. Check cut-
off location if wheel failure damaged cutoff plate. See
Fig. 61.
10. Tighten bearing holddown bolts, bearing setscrews and shaft
setscrews.
11. Field balancing of shaft and wheel is recommended.
IMPORTANT: Replacement shafts must have a diameter
tolerance at bearing mount of
specified parts are recommended.
Lubrication
MOTORS
Lubricate in accordance with nameplate attached to motor or with
manufacturer's recommendations included with motor.
BEARINGS
Fan Bearings
Lubricate fan bearings every 3 months with suitable bearing
grease. Typical lubricants are given in Table 19.
Inlet Vane and Outlet Damper Bearings
These bearings are oil-impregnated. Annually lubricate with a few
drops of nondetergent SAE (Society of Automotive Engineers) 20
oil.
Table 19 — Lubricant Data
MANUFACTURER
Sunoco
Texaco
Texaco
Mobil
* Preferred lubricant because it contains rust and oxidation inhibitors.
+ .0000
nominal. Carrier-
– .001
LUBRICANT
Prestige 42
Multipak 2
Regal AFB-2*
Mobilplex EP No. 1
Fig. 60 — Fan Shaft and Bearing Removal
CUTOFF
39L UNIT SIZE
03
06
08
10
12
15
18
21
25
Fig. 61 — Fan Cutoff Plate Data (in.)
Fan Sled Disassembly
In some cases on vertical units (39LD, 39 LF, or 39LH), it may be
necessary to remove the fan sled (Fig. 55) from the unit and break
it down into smaller components.
59
CUTOFF CLEARANCE
A B
6-5/8 7/8
8 1
10-3/8 1-1/2
9-3/4 1-3/8
9-3/4 1-3/8
12 1-5/8
15-3/4 2
15-3/4 2
20-1/2 2-11/16