Bryant DURAPAC 579F - Manual (Page 31)

— 31 —
IV. EVAPORATOR FAN SERVICE AND REPLACEMENT
A. 579F180 Units (See Fig. 39)
NOTE: To remove belts only, follow Steps 1-6.
1. Remove filter and supply-air section panels.
2. Remove unit top panel.
3. Loosen carriage nuts A and B holding motor mount
assembly to fan scroll side plates.
4. Loosen screw C.
5. Rotate motor mount assembly (with motor attached)
as far as possible away from evaporator coil.
6. Remove belt.
7. Rotate motor mount assembly back past original
position toward evaporator coil.
8. Remove motor mounting nuts D and E (both sides).
9. Lift motor up through top of unit.
10. Reverse above procedure to reinstall motor.
11. Check and adjust belt tension as necessary.
B. 579F216-300 Units (See Fig. 40)
The 579F216-300 units use a fan motor mounting system
that features a slide-out motor mounting plate. To replace or
service the motor, slide out the bracket.
1. Remove the evaporator-fan access panel and the
heating control access panel.
2. Remove the center post (located between the evapora-
tor fan and heating control access panels) and all
screws securing it.
3. Loosen nuts on the 2 carriage bolts in the motor
mounting base.
4. Using jacking bolt under motor base, raise motor to
top of slide and remove belt. Secure motor in this
position by tightening the nuts on the carriage bolts.
5. Remove the belt drive.
6. Remove jacking bolt and tapped jacking bolt plate.
7. Remove the 2 screws that secure the motor mounting
plate to the motor support channel.
8. Remove the 3 screws from the end of the motor sup-
port channel that interfere with the motor slide path.
9. Slide out the motor and motor mounting plate.
10. Disconnect wiring connections and remove the
4 mounting bolts.
11. Remove the motor.
12. To install the new motor, reverse Steps 1-11.
V. BELT TENSION ADJUSTMENT
To adjust belt tension:
1. Loosen fan motor bolts.
2. a.
Size 180 Units:
Move motor mounting plate up or down for
proper belt tension (
1 /
2
in. deflection with one
finger).
b. Size 216-300 Units:
Turn motor jacking bolt to move motor mounting
plate up or down for proper belt tension (
3 /
8
in.
deflection at midspan with one finger [9 lb
force]).
3. Tighten nuts.
4. Adjust bolts and nut on mounting plate to secure
motor in fixed position.
VI. CONDENSER-FAN ADJUSTMENT
A. 579F180,216 Units (Fig. 41)
1. Shut off unit power supply.
2. Remove access panel(s) closest to the fan to be
adjusted.
3. Loosen fan hub setscrews.
4. Adjust fan height on shaft using a straightedge
placed across the fan orifice.
5. Tighten setscrews and replace panel(s).
6. Turn on unit power.
Fig. 39 — 579F180 Evaporator-Fan Motor Adjustment
NOTE: A 3 1 / 2 -in. bolt and threaded plate are included in the installer’s packet.
They should be added to the motor support channel below the motor mounting
plate to aid in raising the motor. The plate part number is 50DP503842. The
adjustment bolt is
3 /
8
-16 x 2 1 /
2
in. LG.
Fig. 40 — 579F216-300 Evaporator-Fan Motor Section