Bryant operation manual III. Evaporator FAN Performance Adjustment Fig, 559F180 Units See Fig

III.EVAPORATOR FAN PERFORMANCE ADJUSTMENT (Fig. 25-27)

Fan motor pulleys are factory set for speed shown in Table 1. To change fan speeds:

1.Shut off unit power supply.

2.a. Size 180 Only: Loosen belt by loosening fan motor mounting plate nuts.

b.Size 216-300 Only: Loosen nuts on the 2 carriage bolts in the motor mounting base. Install jacking bolt and plate under motor base (bolt and plate are shipped in installer's packet). See Fig. 25. Using bolt and plate, raise motor to top of slide and remove belt. Secure motor in this position by tightening the nuts on the carriage bolts.

3.Loosen movable-pulley ¯ange setscrew (see Fig. 25).

4.Screw movable ¯ange toward ®xed ¯ange to increase speed and away from ®xed ¯ange to decrease speed. Increas- ing fan speed increases load on motor. Do not exceed maxi- mum speed speci®ed in Table 1.

See Table 4 for air quantity limits.

5.Set movable ¯ange at nearest keyway of pulley hub and tighten setscrew. (See Table 1 for speed change for each full turn of pulley ¯ange.)

6.Replace and tighten belts. See Belt Tension Adjustment section on page 22.

To align fan and motor pulleys:

1.Loosen fan pulley setscrews.

2.Slide fan pulley along fan shaft.

3.Make angular alignment by loosening motor from mount- ing plate.

IV. EVAPORATOR FAN SERVICE AND REPLACEMENT

A. 559F180 Units (See Fig. 26)

NOTE: To remove belts only, follow Steps 1-6.

1.Remove ®lter and supply-air section panels.

2.Remove unit top panel.

3.Loosen carriage nuts A and B holding motor mount as- sembly 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 posi- tion 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. 559F216-300 Units (See Fig. 27)

The 559F216-300 units use a fan motor mounting system that features a slide-out motor mounting plate. To replace or serv- ice the motor, slide out the bracket.

1.Remove the evaporator-fan access panel and the heat- ing 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 two carriage bolts in the motor mount- ing base.

Fig. 25 Ð Evaporator-Fan Pulley Alignment

and Adjustment

Fig. 26 Ð 559F180 Evaporator-Fan

Motor Section

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